A Secondary Structural Model of the 28S rRNA Expansion Segments D2 and D3 for Chalcidoid Wasps (Hymenoptera: Chalcidoidea)

One Step beyond Species Description: Unveiling a Fine-Scale Diversity within the Genus Dzhanokmenia Kostjukov (Hymenoptera: Eulophidae)

Although Chalcidoidea is one of the megadiverse superfamilies in Hymenoptera, numerous species are still being discovered and described. However, the difficulties in delimiting intra- and interspecific variation hinder this process. In this study, DNA barcoding methods using the COI gene were employed to investigate the morphological variation within Dzhanokmenia Kostjukov, 1977. The nuclear locus, 28S D2, was used to infer a phylogeny to gain an understanding of the relationship of Dzhanokmenia with other potentially close genera. Through a preliminary DNA barcode library established here, including eight species, we calibrated the intraspecific variation in certain diagnostic characters for the new species described here, D. brevifunis Ganbaatar & Cao sp. nov. Maximum likelihood results show that Dzhanokmenia is clustered with the genera associated with Tetrastichus, such as Chaenotetrastichus Graham, 1987, Baryscapus Förster, 1856, Tetrastichus Haliday, 1844, and Oomyzus Rondani, 1870 involved in this study. Our results indicate that the species diversity of Dzhanokmenia is understudied and tentatively confirm that Dzhanokmenia has a potential close relationship with Baryscapus. Along with the DNA barcode library, the referenced phylogeny datasets improve the understanding of the systematic position of Dzhanokmenia within the subfamily Tetrastichinae and the definition of this genus in terms of morphology, thereby facilitating species delimitation, discovery, and description within Dzhanokmenia.

rRNA expansion segment 7 in eukaryotes: from Signature Fold to tentacles

The ribosomal core is universally conserved across the tree of life. However, eukaryotic ribosomes contain diverse rRNA expansion segments (ESs) on their surfaces. Sites of ES insertions are predicted from sites of insertion of micro-ESs in archaea. Expansion segment 7 (ES7) is one of the most diverse regions of the ribosome, emanating from a short stem loop and ranging to over 750 nucleotides in mammals. We present secondary and full-atom 3D structures of ES7 from species spanning eukaryotic diversity. Our results are based on experimental 3D structures, the accretion model of ribosomal evolution, phylogenetic relationships, multiple sequence alignments, RNA folding algorithms and 3D modeling by RNAComposer. ES7 contains a distinct motif, the 'ES7 Signature Fold', which is generally invariant in 2D topology and 3D structure in all eukaryotic ribosomes. We establish a model in which ES7 developed over evolution through a series of elementary and recursive growth events. The data are sufficient to support an atomic-level accretion path for rRNA growth. The non-monophyletic distribution of some ES7 features across the phylogeny suggests acquisition via convergent processes. And finally, illustrating the power of our approach, we constructed the 2D and 3D structure of the entire LSU rRNA of Mus musculus.

Revision of the World Species of Megaphragma Timberlake (Hymenoptera: Trichogrammatidae)

Megaphragma species are important models for basic organismal research, and many are potential biological control agents. We present the first extensive revision of species of the genus Megaphragma based on morphological and molecular data. Our revision includes all previously described species, 6 of which are synonymized, and 22 of which are described here as new. We also provide the first key to all species of the genus and reconstruct their phylogeny based on 28S and CO1 molecular markers. The following species are synonymized with M. longiciliatum Subba Rao: M. aligarhensis Yousuf and Shafee syn. nov.; M. amalphitanum Viggiani syn. nov.; M. decochaetum Lin syn. nov.; M. magniclava Yousuf and Shafee syn. nov.; M. shimalianum Hayat syn. nov.M. anomalifuniculi Yuan and Lou syn. nov. is synonymized with M. polychaetum Lin. The following species are described as new: M. antecessor Polaszek and Fusu sp. nov.; M. breviclavum Polaszek and Fusu sp. nov.; M. chienleei Polaszek and Fusu sp. nov.; M. cockerilli Polaszek and Fusu sp. nov.; M. digitatum Polaszek and Fusu sp. nov.; M. fanenitrakely Polaszek and Fusu sp. nov.; M. funiculatum Fusu, Polaszek, and Viggiani sp. nov.; M. giraulti Viggiani, Fusu, and Polaszek sp. nov.; M. hansoni Polaszek, Fusu, and Viggiani sp. nov.; M. kinuthiae Polaszek, Fusu, and Viggiani sp. nov.; M. liui Polaszek and Fusu sp. nov.; M. momookherjeeae Polaszek and Fusu sp. nov.; M. nowickii Polaszek, Fusu, and Viggiani sp. nov.; M. noyesi Polaszek and Fusu sp. nov.; M. pintoi Viggiani sp. nov.; M. polilovi Polaszek, Fusu, and Viggiani sp. nov.; M. rivelloi Viggiani sp. nov.; M. tamoi Polaszek, Fusu, and Viggiani sp. nov.; M. tridens Fusu, and Polaszek sp. nov.; M. uniclavum Polaszek and Fusu sp. nov.; M. vanlentereni Polaszek and Fusu sp. nov.; M. viggianii Fusu, Polaszek, and Polilov sp. nov.

On the genus Coccophagus Westwood (Hymenoptera, Aphelinidae) from Xishuangbanna Rainforest. Contribution I: Two new species of the Coccophagus varius group, with an identification key and phylogenetic analysis

Two new species belonging to the varius group of Coccophagus, C.breviclavulussp. nov. and C.perlucidussp. nov., are described from Xishuangbanna Rainforest (China, Yunnan). Coccophagusanchoroides (Huang) and C.yunnana Wang, Huang & Polaszek are recorded. A tentative key to world species of this group is provided. Partial nuclear ribosomal 28S-D2 of these four species and other six species were sequenced and subjected to a phylogenetic analysis. Phylogeny of C.varius group is discussed.

First Detection of Ditylenchus destructor Parasitizing Maize in Northeast China

Maize is one of the most important crops in the world. Heilongjiang province has the largest maize area in China. Plant-parasitic nematodes are important agricultural pests, which cause huge economic losses every year and have attracted global attention. Potato rot nematode Ditylenchus destructor is a plant-parasitic nematode with a wide range of hosts and strong survival ability in different environments, which brings risks to agricultural production. In 2020, D. destructor was detected in seven maize fields in Heilongjiang province. Morphological identification and molecular approach were used to characterize the isolated D. destructor. The observed morphological and morphometric characteristics were highly similar and consistent with the existing description. The DNA sequencing on the D2/D3 region of the ribosomal DNA 28S and the phylogenetic analysis showed that D. destructor population obtained from maize and other isolates infesting carrot, sweet potato, and potato were in subclade I supported by a 96% bootstrap value. Additionally, the phylogenetic analysis of the ITS rRNA gene sequence further indicated that this D. destructor population from maize clustered in a clade I group and belonged to ITS rRNA haplotype C. An inoculation experiment revealed that D. destructor was pathogenic on the maize seedlings in pots and caused the disease symptoms in the stem base of maize seedlings. This is the first report of D. destructor causing stem rot of maize in Heilongjiang province, and contributes additional information on disease control and safe production of maize in the region.

Ophelimus bipolaris sp. n. (Hymenoptera, Eulophidae), a New Invasive Eucalyptus Pest and Its Host Plants in China

Eucalyptus species have become one of the most commonly planted trees worldwide, including China, due to their fast growth and various commercial applications. However, the productivity of Eucalyptus plantations has been threatened by exotic invasive insect pests in recent years. Among these pests, gall inducers of the genus Ophelimus of the Eulophidae family are among the most important invasive species in Eucalyptus plantations. We report here for the first time the presence of a new invasive Eucalyptus gall wasp, Ophelimus bipolaris sp. n., in Guangzhou, China, which also represents the first species of the genus reported from China. The identity of the new species was confirmed by an integrative approach combing biological, morphological and molecular evidence. The new species is described and illustrated. This wasp induces galls only on the leaf blade surface of four Eucalyptus species: E. grandis, E. grandis × E. urophylla, E. tereticornis and E. urophylla. Our preliminary observation showed that O. bipolaris could complete a life cycle on E. urophylla in approximately 2 months under local climatic conditions (23.5-30 °C). Considering the severe damage it may cause to Eucalyptus production, further investigations of its biology and control are urgently needed in China.

Investigating the Parasitoid Community Associated with the Invasive Mealybug Phenacoccus solenopsis in Southern China

Simple Summary

The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) is an emerging invasive insect pest in China. Hymenopteran parasitoids have great potential to be used as biological agents to suppress the populations of P. solenopsis in the field. We used an integrated approach of species delimitation, combining morphology with molecular data, to investigate the parasitoid community associated with P. solenopsis from south China. On the basis of both morphological and molecular evidence, we identified 18 hymenopteran parasitoid species belonging to 11 genera of four families. Among these species, eight species are primary parasitoids with Aenasius arizonensis (Girault) (Hymenoptera: Encyrtidae) being the dominant taxon, while the other 10 species are probably hyperparasitoids. These findings can assist in the utility of these parasitoids in the biological control of P. solenopsis.

Abstract

The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), is an emerging invasive insect pest in China. Hymenopteran parasitoids are the key organisms for suppressing populations of P. solenopsis in the field, and therefore could be used as biological agents. Accurate identification of the associated parasitoids is the critical step to assess their potential role in biological control. In this study, we facilitated the identification of the parasitoid composition of P. solenopsis using an integrated approach of species delimitation, combining morphology with molecular data. Eighteen Hymenoptera parasitoid species belonging to 11 genera of four families are recognized based on morphological examination and molecular species delimitation of the mitochondrial cytochrome c oxidase 1 (COI) gene and the 28S rDNA using the automatic barcode gap discovery (ABGD) and the Bayesian Poisson tree processes model (bPTP). Among these species, eight species are primary parasitoids with Aenasius arizonensis (Girault) (Hymenoptera: Encyrtidae) being the dominant taxon, while the other 10 species are probably hyperparasitoids, with a prevalence of Cheiloneurus nankingensis Li & Xu (Hymenoptera: Encyrtidae). These results indicate that parasitoid wasps associated with P. solenopsis from China are diverse and the integrated taxonomic approach applied in this study could enhance the accurate identification of these parasitoids that should be assessed in future biological control programs.

Culicidae-centric metabarcoding through targeted use of D2 ribosomal DNA primers

A practical limitation to many metabarcoding initiatives is that sampling methods tend to collect many non-target taxa, which become “amplicon noise” that can saturate Next Generation Sequencing results and lead to both financial and resource inefficiencies. An available molecular tool that can significantly decrease these non-target amplicons and decrease the need for pre-DNA-extraction sorting of bycatch is the design of PCR primers tailored to the taxa under investigation. We assessed whether the D2 extension segment of the 28S ribosomal operon can limit this shortcoming within the context of mosquito (Culicidae) monitoring. We designed PCR primers that are fully conserved across mosquitos and exclude from amplification most other taxa likely to be collected with current sampling apparatuses. We show that, given enough sequencing depth, D2 is an effective marker for the detection of mosquito sequences within mock genomic DNA pools. As few as 3,050 quality-filtered Illumina reads were able to recover all 17 species in a bulk pool containing as little as 0.2% of constituent DNA from single taxa. We also mixed these mosquito DNA pools with high concentrations of non-Culicidae bycatch DNA and show that the component mosquito species are generally still recoverable and faithful to their original relative frequencies. Finally, we show that there is little loss of fidelity in abundance parameters when pools from degraded DNA samples were sequenced using the D2 primers.

Genome-wide analyses of single nucleotide polymorphisms reveal the consequences of traditional mass-rearing on genetic variation in Aphytis melinus (Hymenoptera: Aphelinidae): the danger of putting all eggs in one basket

BACKGROUND

Aphytis melinus DeBach (Hymenoptera: Aphelinidae) is a highly effective biocontrol agent of the California red scale Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae). It is commercially reared and used for augmentative releases within integrated pest management programs. However, mass rearing of biocontrol agents can result in population bottlenecks and high levels of inbreeding and/or adaptation to the factitious rearing conditions. Although these factors can all negatively impact field performance of biocontrol agents, few empirical studies have examined the genetic consequences of mass rearing. We used double-digest RAD sequencing (ddRADseq) to investigate the effect of traditional mass rearing on genetic variation among insectary colonies of A. melinus relative to wild populations in native (Pakistan) and introduced (California) ranges.

RESULTS

Analyses of up to 9700 single nucleotide polymorphisms (SNPs) revealed that insectary populations had less genomic variation than introduced populations. This was evidenced by fewer private alleles, reduced heterozygosity, and greater missing data in the insectary populations. Further, California insectaries formed a distinct genomic cluster relative to the other samples, a surprising result given that the insectary colonies were putatively established at different times and from different source populations. These differences were evident across most data sets also after we filtered out contaminant DNA from the most common host species (Aspidiotus nerii Bouché and A. aurantii).

CONCLUSION

We hypothesize that this pattern would only result if: (i) directional selection for 'captive' phenotypes produces convergent patterns of genomic variation across insectaries; or (ii) the California insectary colonies were all founded from a unifying source population and/or that the insectaries regularly exchange 'genetic' stocks. We show that RADseq is an effective method to investigate the effects of mass rearing on genetics of biocontrol agents. © 2019 Society of Chemical Industry.

Ophelimus mediterraneus sp. n. (Hymenoptera, Eulophidae): a new Eucalyptus gall wasp in the Mediterranean region

We report here for the first time the presence of Ophelimus mediterraneus sp. n. in Mediterranean Europe. This species appears to be closely related to Ophelimus maskelli, a well-known invasive pest of Eucalyptus. Based on molecular (cytochrome oxidase I, 28S), morphological (multivariate ratio analysis) and bio-ecological investigations, our study gives unambiguous relevant criteria that allow the discrimination between these two species. A full description of O. mediterraneus sp. n. is also provided. The geographic distribution of O. mediterraneus sp. n. as well as its impact on Eucalyptus species needs to be more widely assessed since its presence may have been confused with O. maskelli in their sympatric introduced areas. Further investigations of potential parasitoids in the native area may thus be welcomed to evaluate classical biological control achievability.

Multi-gene phylogeny and divergence estimations for Evaniidae (Hymenoptera)

Ensign wasps (Hymenoptera: Evaniidae) develop as predators of cockroach eggs (Blattodea), have a wide distribution and exhibit numerous interesting biological phenomena. The taxonomy of this lineage has been the subject of several recent, intensive efforts, but the lineage lacked a robust phylogeny. In this paper we present a new phylogeny, based on increased taxonomic sampling and data from six molecular markers (mitochondrial 16S and COI, and nuclear markers 28S, RPS23, CAD, and AM2), the latter used for the first time in phylogenetic reconstruction. Our intent is to provide a robust phylogeny that will stabilize and facilitate revision of the higher-level classification. We also show the continued utility of molecular motifs, especially the presence of an intron in the RPS23 fragments of certain taxa, to diagnose evaniid clades and assist with taxonomic classification. Furthermore, we estimate divergence times among evaniid lineages for the first time, using multiple fossil calibrations. Evaniidae radiated primarily in the Early Cretaceous (134.1-141.1 Mya), with and most extant genera diverging near the K-T boundary. The estimated phylogeny reveals a more robust topology than previous efforts, with the recovery of more monophyletic taxa and better higher-level resolution. The results facilitate a change in ensign wasp taxonomy, with Parevania, and Papatuka, syn. nov. becoming junior synonyms of Zeuxevania, and Acanthinevania, syn. nov. being designated as junior synonym of Szepligetella. We transfer 30 species to Zeuxevania, either reestablishing past combinations or as new combinations. We also transfer 20 species from Acanthinevania to Szepligetella as new combinations.

When taxonomy and biological control researchers unite: Species delimitation of Eadya parasitoids (Braconidae) and consequences for classical biological control of invasive paropsine pests of Eucalyptus

The invasive eucalyptus tortoise beetle, Paropsis charybdis, defoliates plantations of Eucalyptus nitens in New Zealand. Recent efforts to identify host specific biological control agents (parasitoids) from Tasmania, Australia, have focused on the larval parasitoid wasp, Eadya paropsidis (Braconidae), first described in 1978. In Tasmania, Eadya has been reared from Paropsisterna agricola (genus abbreviated Pst.), a smaller paropsine that feeds as a larva on juvenile rather than adult foliage of Eucalyptus nitens. To determine which of the many paropsine beetle hosts native to Tasmania are utilized by E. paropsidis, and to rule out the presence of cryptic species, a molecular phylogenetic approach was combined with host data from rearing experiments from multiple locations across six years. Sampling included 188 wasps and 94 beetles for molecular data alone. Two mitochondrial genes (COI and Cytb) and one nuclear gene (28S) were analyzed to assess the species limits in the parasitoid wasps. The mitochondrial genes were congruent in delimiting four separate phylogenetic species, all supported by morphological examinations of Eadya specimens collected throughout Tasmania. Eadya paropsidis was true to the type description, and was almost exclusively associated with P. tasmanica. A new cryptic species similar to E. paropsidis, Eadya sp. 3, was readily reared from Pst. agricola and P. charybdis from all sites and all years. Eadya sp. 3 represents the best candidate for biological control of P. charybdis and was determined as the species undergoing host range testing in New Zealand for its potential as a biological control agent. Another new species, Eadya sp. 1, was morphologically distinctive and attacked multiple hosts. The most common host was Pst. variicollis, but was also reared from Pst. nobilitata and Pst. selmani. Eadya sp. 1 may have potential for control against Pst. variicollis, a new incursion in New Zealand, and possibly Pst. selmani in Ireland. Our molecular data suggests that Pst. variicollis is in need of taxonomic revision and the geographic source of the beetle in New Zealand may not be Tasmania. Eadya sp. 2 was rarely collected and attacked P. aegrota elliotti and P. charybdis. Most species of Eadya present in Tasmania are not host specific to one beetle species alone, but demonstrate some host plasticity across the genera Paropsisterna and Paropsis. This study is an excellent example of collaborative phylogenetic and biological control research prior to the release of prospective biological control agents, and has important implications for the Eucalyptus industry worldwide.

Microbial synthesis of mammalian metabolites of spironolactone by thermophilic fungus Thermomyces lanuginosus

Mesophilic fungi are well recognized as models of mammalian drug metabolism. Thermophilic fungi remained unexplored despite having a unique mechanism of growing at higher temperatures and performing wide diverse reactions. The present investigation is directed to isolate a promising thermophilic fungal strain capable of biotransformation using spironolactone as a model drug. Two-stage fermentation protocol was followed for the process. The transformation of spironolactone was identified by HPLC and structure elucidation of the metabolites was done with the help of LC-MS/MS analysis and previous reports. A strain of Thermomyces lanuginosus isolated from decomposed banana peel waste was found to be most promising in transforming spironolactone to 4 metabolites viz.7α-thiospironolactone (M1) canrenone (M2), 7α-thiomethylspironolactone (M3) and 6β-OH-7α-thiomethylspironolactone (M4), the major mammalian metabolites reported previously. The synthesis of metabolites of spironolactone by T. lanuginosus similar to mammals clearly states that this fungus possess enzyme system similar to mammals. Hence, this fungus has the potential to use as a model organism for studying drug metabolism.

Preliminary Investigation of Species Diversity of Rice Hopper Parasitoids in Southeast Asia

Ongoing intensification of rice production systems in Southeast Asia is causing devastating yield losses each year due to rice hoppers. Their continuing development of immunity to resistant rice varieties and pesticide applications further complicates this problem. Hence, there is a high demand for biological control agents of rice hoppers. Egg parasitoid wasps are among the most important natural enemies of rice hoppers, such as Nilaparvata lugens and Nephotettix spp. However, our knowledge of their diversity is still very limited, due to their small size and the lack of available morphological information. Classifying these parasitoids is the first step to properly understanding their role in the rice agroecosystem. We used traditional morphological identification, as well as DNA sequencing of the 28S rRNA and the COI genes, to investigate the diversity of four important hopper egg parasitoid genera in the Philippines. Parasitoids of the genera Anagrus, Oligosita, Gonatocerus, and Paracentrobia were collected in eight study landscapes located in Luzon. Our findings illustrate that characterization of species diversity using morphological and molecular analyses were concordant only for the genus Paracentrobia. The genera Anagrus and Gonatocerus exhibited more genetic diversity than estimated with the morphological analysis, while the opposite was observed for Oligosita. This is the first study investigating the molecular diversity of rice hopper parasitoids in the Philippines. More research combining morphological, behavioral, and molecular methods, as well as the establishment of a comprehensive DNA database, are urgently needed to assess the performance and suitability of these organisms as biocontrol agents.

Unravelling mummies: cryptic diversity, host specificity, trophic and coevolutionary interactions in psyllid - parasitoid food webs

BACKGROUND

Parasitoids are hyperdiverse and can contain morphologically and functionally cryptic species, making them challenging to study. Parasitoid speciation can arise from specialisation on niches or diverging hosts. However, which process dominates is unclear because cospeciation across multiple parasitoid and host species has rarely been tested. Host specificity and trophic interactions of the parasitoids of psyllids (Hemiptera) remain mostly unknown, but these factors are fundamentally important for understanding of species diversity, and have important applied implications for biological control.

RESULTS

We sampled diverse parasitoid communities from eight Eucalyptus-feeding psyllid species in the genera Cardiaspina and Spondyliaspis, and characterised their phylogenetic and trophic relationships using a novel approach that forensically linked emerging parasitoids with the presence of their DNA in post-emergence insect mummies. We also tested whether parasitoids have cospeciated with their psyllid hosts. The parasitoid communities included three Psyllaephagus morphospecies (two primary and, unexpectedly, one heteronomous hyperparasitoid that uses different host species for male and female development), and the hyperparasitoid, Coccidoctonus psyllae. However, the number of genetically delimited Psyllaephagus species was three times higher than the number of recognisable morphospecies, while the hyperparasitoid formed a single generalist species. In spite of this, cophylogenetic analysis revealed unprecedented codivergence of this hyperparasitoid with its primary parasitoid host, suggesting that this single hyperparasitoid species is possibly diverging into host-specific species. Overall, parasitoid and hyperparasitoid diversification was characterised by functional conservation of morphospecies, high host specificity and some host switching between sympatric psyllid hosts.

CONCLUSIONS

We conclude that host specialisation, host codivergence and host switching are important factors driving the species diversity of endoparasitoid communities of specialist host herbivores. Specialisation in parasitoids can also result in heteronomous life histories that may be more common than appreciated. A host generalist strategy may be rare in endoparasitoids of specialist herbivores despite the high conservation of morphology and trophic roles, and endoparasitoid species richness is likely to be much higher than previously estimated. This also implies that the success of biological control requires detailed investigation to enable accurate identification of parasitoid-host interactions before candidate parasitoid species are selected as biological control agents for target pests.

Primary parasitoids of red scale (Aonidiella aurantii) in Australia and a review of their introductions from Asia

We used morphological and molecular differences to confirm the identities of red scale (Aonidiella aurantii) and yellow scale (A. citrina), and their primary parasitoids, in Australia. An extension to the distribution of yellow scale was confirmed. Six primary parasitoids of red scale were identified: Aphytis chrysomphali, A. lingnanensis, A. melinus, Comperiella bifasciata, Encarsia citrina, and E. perniciosi. With the exception of A. lingnanensis, these parasitoids, and a species of Aphelinus, were detected in association with red scale during studies in citrus orchards in coastal New South Wales between 2009 and 2012. Two races of A. melinus were recorded: one from the Indian Subcontinent, the other previously only recorded in China. The studies, and reviews of historical records, led us to conclude that 4 parasitoids, A. lingnanensis, C. bifasciata, and both species of Encarsia, were present in Australia before successful or unsuccessful formal introductions between 1902 and 1970. The A. melinus race previously recorded in China may also have been present before the Indian Subcontinent race was formally introduced in 1961. We suggest the possibility that the natural distribution of some of the parasitoids may include East and Southeast Asia, and parts of Australasia. We found no reports of native armored scales being recorded on species and hybrids of Citrus introduced to Australia, and no reports of introduced armored scales being recorded on native Rutaceae, including 6 species of Citrus. However, we subsequently recorded yellow scale on Geijera parviflora, a native rutaceous tree.

Clarification of the Phylogenetic Framework of the Tribe Baorini (Lepidoptera: Hesperiidae: Hesperiinae) Inferred from Multiple Gene Sequences

Members of the skipper tribe Baorini generally resemble each other and are characterized by dark brown wings with hyaline white spots. These shared characteristics have caused difficulties with revealing the relationships among genera and species in the group, and some conflicting taxonomic views remain unresolved. The present study aims to infer a more comprehensive phylogeny of the tribe using molecular data, to test the monophyly of the tribe as well as the genera it includes in order to clarify their taxonomic status, and finally to revise the current classification of the group. In order to reconstruct a phylogenetic tree, the mitochondrial COI-COII and 16S genes as well as the nuclear EF-1α and 28S genes were analyzed using parsimony, maximum likelihood, and Bayesian inference. The analysis included 67 specimens of 41 species, and we confirmed the monophyly of Baorini, and revealed that 14 genera are well supported. The genus Borbo is separated into three clades: Borbo, Pseudoborbo, and Larsenia gen. nov. We confirmed that Polytremis is polyphyletic and separated into three genera: Polytremis, Zinaida, and Zenonoida gen. nov., and also confirmed that the genus Prusiana is a member of the tribe. Relationships among some genera were strongly supported. For example, Zenonia and Zenonoida were found to be sister taxa, closely related to Zinaida and Iton, while Pelopidas and Baoris were also found to cluster together.

Gene expression of protein-coding and non-coding RNAs related to polyembryogenesis in the parasitic wasp, Copidosoma floridanum

Polyembryony is a unique form of development in which many embryos are clonally produced from a single egg. Polyembryony is known to occur in many animals, but the underlying genetic mechanism responsible is unknown. In a parasitic wasp, Copidosoma floridanum, polyembryogenesis is initiated during the formation and division of the morula. In the present study, cDNA libraries were constructed from embryos at the cleavage and subsequent primary morula stages, times when polyembryogenesis is likely to be controlled genetically. Of 182 and 263 cDNA clones isolated from these embryos, 38% and 70%, respectively, were very similar to protein-coding genes obtained from BLAST analysis and 55 and 65 clones, respectively, were stage-specific. In our libraries we also detected a high frequency of long non-coding RNA. Some of these showed stage-specific expression patterns in reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis. The stage-specificity of expression implies that these protein-coding and non-coding genes are related to polyembryogenesis in C. floridanum. The non-coding genes are not similar to any known non-coding RNAs and so are good candidates as regulators of polyembryogenesis.

Application of DNA barcoding to the identification of Hymenoptera parasitoids from the soybean aphid (Aphis glycines) in China

Aphis glycines Matsumura is an important pest of soybean in Asia and North America. Hymenoptera parasitoids play a key role in the control of the soybean aphid. The correct identification of parasitoids is a critical step that precedes the assessment of their potential biological control agents. Accurate identification of the majority of the species attacking the soybean aphid often requires elaborate specimen preparation and expert taxonomic knowledge. In this study, we facilitated the identification of soybean aphid parasitoids by applying a DNA barcoding approach following a preliminary morphological identification. We generated DNA sequence data from the mitochondrial COI gene and the D2 region of 28S rDNA to assess the genetic variation within and between parasitoid species emerging from the soybean aphid in China. Fifteen Hymenoptera parasitoid species belonging to 10 genera of five families were identified with little intra-specific variation (0.09% ± 0.06% for 28S and 0.36% ± 0.18% for COI) and large inter-specific divergence (30.46% ± 3.42% for 28S and 20.4% ± 1.20% for COI).

Systematics and biology of the aberrant intertidal parasitoid wasp Echthrodesis lamorali Masner (Hymenoptera : Platygastridae s.l.): a parasitoid of spider eggs

The platygastroid wasp Echthrodesis lamorali has been of considerable interest since its description in 1968, primarily because of its highly modified, densely pilose, wingless body, its distribution and unusual biology. The species is endemic to the Cape Peninsula, South Africa, where it is an endoparasitoid of eggs of the marine spiders Desis formidabilis (Desidae) and Amaurobioides africanus (Anyphaenidae) in the intertidal region. Although a highly aberrant monospecific genus, the phylogenetic relationships of Echthrodesis are confused, in part due to convergence in body form across numerous unrelated platygastroid genera. We used sequence data from the nuclear 28S rRNA and 18S rDNA genes, and the mitochondrial cytochrome oxidase 1 (CO1) gene, to determine the phylogenetic affinities of E. lamorali. We present a revised taxonomic description for the genus and species, as well as new morphological information on the structure of its mouthparts and ovipositor system. Phylogenetic analyses of molecular data place E. lamorali within one of two independent clades of platygastroid wasps that use spider eggs as hosts. Echthrodesis is sister to a group of three genera: Neobaeus (New Zealand; host unconfirmed); Mirobaeoides (Australia; spider eggs); and Embidobia (near cosmopolitan; embiid eggs). Details on the biology, behaviour and morphological adaptations of E. lamorali are provided.

Utility of divergent domains of 28S ribosomal RNA in species discrimination of paramphistomes (Trematoda: Digenea: Paramphistomoidea)

Among the digenetic trematodes, paramphistomes are known to be the causative agent of "amphistomiasis" or the stomach fluke disease of domestic and wild animals, mainly ruminants. The use of 28S (divergent domains) and 18S rRNA for phylogenetic inference is significantly warranted for these flukes since it is as yet limited to merely the exploration of the second internal transcribed spacer (ITS2) region. The present study intended to explore the divergent domains (D1-D3) of 28S rRNA and simultaneously equate the phylogenetic information with 18S rRNA in paramphistomes. Divergence of the 28S rRNA domains was evident amongst the divergent (D) domains, where D1 domain emerged as the most variable and D2, the most robust domain, since the latter could provide a higher resolution of the species. D2 was the only domain that comprised compensatory mutations in the helices of its structural constraints; this domain is thus well suited for species distinction and may be considered a potential DNA barcode complementary to mitochondrial DNA. 28S (D1 + D2 + D3) rRNA provided a significant resolution of the taxa corroborating with the taxonomy of these flukes and thus proved to be more robust as a phylogenetic marker for lower levels than 18S rRNA. Phylogenetic inferences of paramphitomes are still scarcely explored; additional data from other taxa belonging to this family may estimate better the biodiversity of these flukes.

Hydrophylita (Lutzimicron) emporos Shih & Polaszek (Hymenoptera: Trichogrammatidae) from Taiwan, parasitising eggs, and phoretic on adults, of the damselfly Psolodesmus mandarinus mandarinus (Zygoptera: Calopterygidae)

Hydrophylita emporos n. sp. reared from eggs of Psolodesmus mandarinus mandarinus McLachlan (Zygoptera: Calopterygidae) in Taiwan is described. This is the first species of Hydrophylita to be described from the Old World, and the first record of phoresy in the genus. Adult females were observed aggregating at the base of the female damselfly’s abdomen. When the damselfly begins ovipositing, females move to the tip of the abdomen, enter the water and quickly locate eggs for parasitising. The article contains links to video footage of this process.

Identification, molecular characterization, and evolution of group I introns at the expansion segment D11 of 28S rDNA in Rhizoctonia species

The nuclear ribosomal DNA of Rhizoctonia species is polymorphic in terms of the nucleotide composition and length. Insertions of 349-410 nucleotides in length with characteristics of group I introns were detected at a single insertion point at the expansion segment D11 of 28S rDNA in 12 out of 64 isolates. Eleven corresponded to Rhizoctonia solani (teleomorph: Thanatephorous) and one (AG-Q) to Rhizoctonia spp. (teleomorph: Ceratobasidium). Sequence data showed that all but AG-Q contained conserved DNA catalytic core regions (P, Q, R, and S) essential for selfsplicing. The predicted secondary structure revealed that base-paired helices corresponded to subgroup IC1. Isolates from same anastomosis group and even subgroups within R. solani were variable with regard to possession of introns. Phylogenetic analyses indicated that introns were vertically transmitted. Unfortunately, sequence data from the conserved region from all 64 isolates were not useful for delimiting species. Analyses with IC1 introns at same insertion point, of both Ascomycota and Basidiomycota indicated the possibility of horizontal transfer at this site. The present study uncovered new questions on evolutionary pattern of change of these introns within Rhizoctonia species.

Phylogeny and biogeography of southern African spoon-winged lacewings (Neuroptera: Nemopteridae: Nemopterinae)

Nemopteridae are a charismatic family of lacewings characterised by uniquely extended hind wings. They are an ancient widespread group in the drier regions of the world. The family comprises two subfamilies, Crocinae (thread-wings) and Nemopterinae (spoon- and ribbon-wings). The present distribution of the family has been largely influenced by the vicariant events of plate tectonics, resulting in relict populations in some parts of the world and extensive evolutionary radiations in others, particularly southern Africa where the vast majority of the species are endemic to the Western and Northern Cape Provinces of South Africa. This study aimed to establish the validity of the 11 currently recognised genera and infer their biogeographic history using molecular sequence data from four gene regions. The hypothesis that the Cape nemopterines co-evolved with certain taxa in the Cape Floristic Region was also tested. Phylogenetic analysis supports seven of the 11 currently recognised genera. The crown age of the Nemopterinae is estimated to be at ca. 145.6 Mya, indicating that the group has been present since the late Jurassic. Most of the genera appear to have diversified during the middle Eocene and into the middle Miocene (ca. 44-11 Mya) with recent rapid radiation of several of the genera occurring during the late Miocene (ca. 6-4.5 Mya). While these data support an initial radiation with the Rushioideae (Aizoaceae) it is recommended that further study including observations and gut content be carried out.

Phylogenetic study of nine species of freshwater monogeneans using secondary structure and motif prediction from India

The present study was performed to identify and validate monogenean species from different piscine hosts using molecular tools. Nine species of freshwater monogeneans were collected from gills and skin of freshwater fishes at Hastinapur, Meerut, India. After microscopic examination, molecular analysis was performed utilizing 28S gene marker. Phylogenetic analysis indicated the validation and systematic position of these nine different monogeneans belongs to the Dactylogyridae and Gyrodactylidae families. The findings also confirm that the 28S rDNA sequence is highly conserved and may prove to be useful in taxonomic studies of parasitic platyhelminthes. Besides this, the study is also supplemented by molecular morphometrics that is based on 28S secondary structure homologies of nine monogenean species. The data indicate that 28S motifs i.e., ≤ 50bp in size can also be considered a promising tool for monogenean species identification and their validation.

DNA barcoding of six Ceroplastes species (Hemiptera: Coccoidea: Coccidae) from China

Ceroplastes Gray (wax scales) is one of the genera of Coccidae, most species of which are considered to be serious economic pests. However, identification of Ceroplastes species is always difficult owing to the shortage of easily distinguishable morphological characters. Mitochondrial cytochrome c oxidase I (COI) sequences (or DNA barcodes) and the D2 expansion segments of the large subunit ribosomal RNA gene 28S were used for accurate identification of six Ceroplastes species (C. floridensis Comstock, C. japonicus Green, C. ceriferus (Fabricius), C. pseudoceriferus Green, C. rubens Maskell and C. kunmingensis Tang et Xie) from 20 different locations in China. For COI data, low G·C content was found in all species, averaging about 20.4%. Sequence divergences (K2P) between congeneric species averaged 12.19%, while intra-specific divergences averaged 0.42%. All 112 samples fell into six reciprocally monophyletic clades in the COI neighbour-joining (NJ) tree. The NJ tree inferred from 28S showed almost same results, but samples of two closely related species, C. ceriferus and C. pseudoceriferus, were clustered together. This research indicates that the standard barcode region of COI can efficiently identify similar Ceroplastes species. This study provides an example of the usefulness of barcoding for Ceroplastes identification.

Testing the emergence of New Caledonia: fig wasp mutualism as a case study and a review of evidence

While geologists suggest that New Caledonian main island (Grande Terre) was submerged until ca 37 Ma, biologists are struck by the presence of supposedly Gondwanan groups on the island. Among these groups are the Oreosycea fig trees (Ficus, Moraceae) and their Dolichoris pollinators (Hymenoptera, Agaonidae). These partners are distributed in the Paleotropics and Australasia, suggesting that their presence on New Caledonia could result from Gondwanan vicariance. To test this hypothesis, we obtained mitochondrial and nuclear markers (5.3 kb) from 28 species of Dolichoris, used all available sequences for Oreosycea, and conducted phylogenetic and dating analyses with several calibration strategies. All our analyses ruled out a vicariance scenario suggesting instead that New Caledonian colonization by Dolichoris and Oreosycea involved dispersal across islands from Sundaland ca 45.9-32.0 Ma. Our results show that successful long-distance dispersal of obligate mutualists may happen further suggesting that presence of intimate mutualisms on isolated islands should not be used as a priori evidence for vicariance. Comparing our results to a review of all the published age estimates for New Caledonian plant and animal taxa, we showed that support for a vicariant origin of the island biota is still lacking. Finally, as demonstrating a causal relationship between geology and biology requires independent evidence, we argue that a priori assumptions about vicariance or dispersal should not be used to constrain chronograms. This circular reasoning could lead to under or overestimation of age estimates.

A molecular phylogeny of the Chalcidoidea (Hymenoptera)

Chalcidoidea (Hymenoptera) are extremely diverse with more than 23,000 species described and over 500,000 species estimated to exist. This is the first comprehensive phylogenetic analysis of the superfamily based on a molecular analysis of 18S and 28S ribosomal gene regions for 19 families, 72 subfamilies, 343 genera and 649 species. The 56 outgroups are comprised of Ceraphronoidea and most proctotrupomorph families, including Mymarommatidae. Data alignment and the impact of ambiguous regions are explored using a secondary structure analysis and automated (MAFFT) alignments of the core and pairing regions and regions of ambiguous alignment. Both likelihood and parsimony approaches are used to analyze the data. Overall there is no impact of alignment method, and few but substantial differences between likelihood and parsimony approaches. Monophyly of Chalcidoidea and a sister group relationship between Mymaridae and the remaining Chalcidoidea is strongly supported in all analyses. Either Mymarommatoidea or Diaprioidea are the sister group of Chalcidoidea depending on the analysis. Likelihood analyses place Rotoitidae as the sister group of the remaining Chalcidoidea after Mymaridae, whereas parsimony nests them within Chalcidoidea. Some traditional family groups are supported as monophyletic (Agaonidae, Eucharitidae, Encyrtidae, Eulophidae, Leucospidae, Mymaridae, Ormyridae, Signiphoridae, Tanaostigmatidae and Trichogrammatidae). Several other families are paraphyletic (Perilampidae) or polyphyletic (Aphelinidae, Chalcididae, Eupelmidae, Eurytomidae, Pteromalidae, Tetracampidae and Torymidae). Evolutionary scenarios discussed for Chalcidoidea include the evolution of phytophagy, egg parasitism, sternorrhynchan parasitism, hypermetamorphic development and heteronomy.

Phylogeny and evolution of life-history strategies in the Sycophaginae non-pollinating fig wasps (Hymenoptera, Chalcidoidea)

BACKGROUND

Non-pollinating Sycophaginae (Hymenoptera, Chalcidoidea) form small communities within Urostigma and Sycomorus fig trees. The species show differences in galling habits and exhibit apterous, winged or dimorphic males. The large gall inducers oviposit early in syconium development and lay few eggs; the small gall inducers lay more eggs soon after pollination; the ostiolar gall-inducers enter the syconium to oviposit and the cleptoparasites oviposit in galls induced by other fig wasps. The systematics of the group remains unclear and only one phylogeny based on limited sampling has been published to date. Here we present an expanded phylogeny for sycophagine fig wasps including about 1.5 times the number of described species. We sequenced mitochondrial and nuclear markers (4.2 kb) on 73 species and 145 individuals and conducted maximum likelihood and Bayesian phylogenetic analyses. We then used this phylogeny to reconstruct the evolution of Sycophaginae life-history strategies and test if the presence of winged males and small brood size may be correlated.

RESULTS

The resulting trees are well resolved and strongly supported. With the exception of Apocrytophagus, which is paraphyletic with respect to Sycophaga, all genera are monophyletic. The Sycophaginae are divided into three clades: (i) Eukoebelea; (ii) Pseudidarnes, Anidarnes and Conidarnes and (iii) Apocryptophagus, Sycophaga and Idarnes. The ancestral states for galling habits and male morphology remain ambiguous and our reconstructions show that the two traits are evolutionary labile.

CONCLUSIONS

The three main clades could be considered as tribes and we list some morphological characters that define them. The same biologies re-evolved several times independently, which make Sycophaginae an interesting model to test predictions on what factors will canalize the evolution of a particular biology. The ostiolar gall-inducers are the only monophyletic group. In 15 Myr, they evolved several morphological adaptations to enter the syconia that make them strongly divergent from their sister taxa. Sycophaginae appears to be another example where sexual selection on male mating opportunities favored winged males in species with small broods and wingless males in species with large broods. However, some species are exceptional in that they lay few eggs but exhibit apterous males, which we hypothesize could be due to other selective pressures selecting against the re-appearance of winged morphs.

Phylogeny of the African ball-rolling dung beetle genus Epirinus Reiche (Coleoptera:Scarabaeidae:Scarabaeinae)

Recent phylogenetic analyses have pointed to the dung beetle genus Epirinus as the putative African ancestral roller group. Consequently, we tested the roller status of species in the genus with observational studies and constructed a molecular phylogeny based on partial sequences of two mitochondrial and two nuclear genes for 16 of 29 species. Tested species were confirmed to be dung rollers. Monophyly of the genus was confirmed, lending support to the synonymy of the wingless genus Endroedyantus with Epirinus. Moreover, the phylogenetic hypothesis was found to have a similar topology with a previously published one based on morphological data. A combined molecular and morphology analysis showed congruence between the molecular and morphological datasets. The loss of flight in some species and estimated divergence dates within Epirinus are discussed.

Did dung beetles arise in Africa? A phylogenetic hypothesis based on five gene regions

Scarabaeinae dung beetle phylogenetics are poorly understood, although recent phylogenetic reconstruction based on morphology and molecular analyses are congruent on the hypothesis that the oldest Gondwana tribes are polyphyletic and that representatives of the ancestral groups are found in Africa. We present a molecular phylogeny of the African representatives of the two oldest tribes, Canthonini (the putative ancestor of all "rollers") and Dichotomiini (thought to represent the ancestral "tunnellers"), based on partial sequence data from two mitochondrial and three nuclear genes, extracted from eight of the nine dichotomiine genera and 17 of the 23 genera of Canthonini. Three well-supported lineages were consistently obtained. Divergence times estimated the origin of the two tribes at around 56 million years ago (MYA) with the splits of the three dung beetle lineages being estimated to have taken place between 40 and 34MYA. The ages of these splits and subsequent radiation of the modern dung beetle groups concur with those predicted by the fossil record and coincide with the proposed age of radiation of the large mammal groups with whose dung most African dung beetles are still associated. Dispersal of dung beetle groups from Africa is proposed as a biogeographic model, and evidence is presented that dung beetles disperse quickly and widely across continents, and even oceans.

Molecular dating and biogeography of fig-pollinating wasps

Figs and fig-pollinating wasps are obligate mutualists that have coevolved for over 60 million years. But when and where did pollinating fig wasps (Agaonidae) originate? Some studies suggest that agaonids arose in the Late Cretaceous and the current distribution of fig-wasp faunas can be explained by the break-up of the Gondwanan landmass. However, recent molecular-dating studies suggest divergence time estimates that are inconsistent with the Gondwanan vicariance hypothesis and imply that long distance oceanic dispersal could have been an important process for explaining the current distribution of both figs and fig wasps. Here, we use a combination of phylogenetic and biogeographical data to infer the age, the major period of diversification, and the geographic origin of pollinating fig wasps. Age estimates ranged widely depending on the molecular-dating method used and even when using the same method but with slightly different constraints, making it difficult to assess with certainty a Gondwanan origin of agaonids. The reconstruction of ancestral areas suggests that the most recent common ancestor of all extant fig-pollinating wasps was most likely Asian, although a southern Gondwana origin cannot be rejected. Our analysis also suggests that dispersal has played a more important role in the development of the fig-wasp biota than previously assumed.

Can comprehensive background knowledge be incorporated into substitution models to improve phylogenetic analyses? A case study on major arthropod relationships

BACKGROUND

Whenever different data sets arrive at conflicting phylogenetic hypotheses, only testable causal explanations of sources of errors in at least one of the data sets allow us to critically choose among the conflicting hypotheses of relationships. The large (28S) and small (18S) subunit rRNAs are among the most popular markers for studies of deep phylogenies. However, some nodes supported by this data are suspected of being artifacts caused by peculiarities of the evolution of these molecules. Arthropod phylogeny is an especially controversial subject dotted with conflicting hypotheses which are dependent on data set and method of reconstruction. We assume that phylogenetic analyses based on these genes can be improved further i) by enlarging the taxon sample and ii) employing more realistic models of sequence evolution incorporating non-stationary substitution processes and iii) considering covariation and pairing of sites in rRNA-genes.

RESULTS

We analyzed a large set of arthropod sequences, applied new tools for quality control of data prior to tree reconstruction, and increased the biological realism of substitution models. Although the split-decomposition network indicated a high noise content in the data set, our measures were able to both improve the analyses and give causal explanations for some incongruities mentioned from analyses of rRNA sequences. However, misleading effects did not completely disappear.

CONCLUSION

Analyses of data sets that result in ambiguous phylogenetic hypotheses demand for methods, which do not only filter stochastic noise, but likewise allow to differentiate phylogenetic signal from systematic biases. Such methods can only rely on our findings regarding the evolution of the analyzed data. Analyses on independent data sets then are crucial to test the plausibility of the results. Our approach can easily be extended to genomic data, as well, whereby layers of quality assessment are set up applicable to phylogenetic reconstructions in general.

18S rRNA hyper-elongation and the phylogeny of Euhemiptera (Insecta: Hemiptera)

The small subunit of nuclear ribosomal RNA (SSU nrRNA), whose sedimentation is mostly 18S in eukaryotes, is considered a relatively conservative marker for resolving phylogenetic relationship at the order level or higher. Length variation in SSU nrDNA is common, and can be rather large in some groups. In studies of Hexapoda phylogeny, the SSU nrDNA has been repeatedly used as a marker. Sternorrhyncha has been rarely included. The lengths of SSU nrDNAs of sternorrhynchids, the basal group of Hemiptera identified in the previous study are 0.3-0.6 kb longer than the usual ones in Hexapoda (1.8-1.9 kb). To use the entire SSU nrDNA sequences or the length-variable parts could cause alignment trouble and therefore affect phylogenetic results, as shown in this study of Euhemiptera phylogeny. Two problems are particularly noticeable. One is that two hyper-variable regions flanking a short length-conservative region could become overlapped in the alignment. This will destroy the positional homology over a larger range. The other is that, when a base pair in a stem of the secondary structure is located near the length-variable regions (LVRs), the simultaneous positional homology of these two bases in the pair is always lost in the alignment results. In this study, the secondary structure model of Hexapoda SSU nrRNA was slightly adjusted and the LVR distributions in it were finely positioned. The noise caused by the hyper LVRs was eliminated and the simultaneous homology for the paired bases was recovered based on the secondary structure model. These corrections improved the quality of the data matrix and hence improved the resolving behavior of the algorithm used. This study provided more convincing evidence for resolving the Euhemiptera suborders phylogeny as (Archaeorrhyncha+(Clypeorrhyncha+(Coleorrhyncha+Heteroptera))). This result provided a more solid background for outgroup determination according to the phylogenetic studies inside each suborder. The problems caused by LVRs have seldom been well addressed. As phylogenetic reconstruction depends more on the data matrix itself than on the algorithm, and length variation of SSU/LSU rRNA exists more or less in any group, it is necessary to closely investigate the effect of rRNA length variation on alignment and phylogenetic reconstruction in more groups.

Comparison of five allopatric fruit fly parasitoid populations (Psyttalia species) (Hymenoptera: Braconidae) from coffee fields using morphometric and molecular methods

Morphometric studies of five allopatric parasitoid populations (genus Psyttalia Walker) from coffee plantations in Cameroon (Nkolbisson), Ghana (Tafo) and Kenya (Rurima, Ruiru and Shimba Hills) and one non-coffee population (from Muhaka, Kenya) were compared with individuals of Psyttalia concolor (Szépligeti), a species released in several biological control programmes in the Mediterranean Region since the 20th Century. Analyses of wing vein measurements showed the second submarginal cell of the fore wing and its adjoining veins had the heaviest principal component weights and served as the main contributing variables in the diagnostic differentiation of the populations. Two populations (Rurima and Ruiru) were found to be the closest to each other and with the strongest phenetic affinity toward P. concolor (and forming one cluster). Populations from Shimba Hills (of unknown identity), Nkolbisson (P. perproximus (Silvestri)) and Tafo formed a second cluster and were separated from P. concolor. Comparison using amplified fragment length polymorphism (AFLP) also showed the Shimba, Nkolbisson and Tafo populations forming a cluster in a dendrogram generated from their genetic distances, with the Shimba and Tafo populations placed as the most closely related species. Based on consistent morphological similarities, morphometric and ecological data coupled with the genetic evidence from AFLP data, the Shimba population is suggested as belonging to the P. perproximus group and, thus, represents a new occurrence record in Kenya. Our results also support earlier conclusion from cross mating data that populations from Rurima and Ruiru belong to the Psyttalia concolor species-group.

Molecular systematics of the Kakaducarididae (Crustacea: Decapoda: Caridea)

The systematic relationships of the freshwater shrimp family, Kakaducarididae, were examined using mitochondrial and nuclear DNA sequences. Combined nuclear (18S rDNA, 28S rDNA, Histone) and mitochondrial (16S rDNA) analyses placed the kakaducaridid genera, Kakaducaris and Leptopalaemon, as a strongly supported clade within the Palaemonidae, in a close relationship with the genus Macrobrachium. Monophyly of the Australian Kakaducarididae was strongly supported by the molecular data. Estimated net divergence times between Kakaducaris and Leptopalaemon using mitochondrial 16S rDNA equate to a late Miocene/Pliocene split. Within Leptopalaemon, each locality was distinct for mitochondrial COI haplotypes, suggesting long-term isolation or recent genetic bottlenecks, a lack of contemporary gene flow amongst sites and a small Ne. Mitochondrial groupings within Leptopalaemon were largely congruent with several previously recognised morphotypes. Estimated net divergence times between L. gagadjui and the new Leptopalaemon morphotypes equate to a split in the late Pliocene/early Pleistocene. The hypothesis that the Kakaducarididae is comprised of relict species in specialised ecological niches is not supported by the molecular data, which instead suggest a relatively recent origin for the group in northern Australia, sometime in the late Miocene or Pliocene.