Morphological and molecular systematic review of Marphysa Quatrefages, 1865 (Annelida: Eunicidae) species from South Africa

Four new species of Marphysa (Annelida, Eunicida, Eunicidae) from the east coast of Peninsular Malaysia

Four new species of Marphysa are described from Terengganu state on the east coast of Peninsular Malaysia, using morphological and molecular (cytochrome oxidase subunit I (COI) gene) data. These species belong to different groups of Marphysa: Marphysakertehensis sp. nov. belongs to Group A (Mossambica), Marphysamerchangensis sp. nov. and Marphysasetiuense sp. nov. belong to Group B (Sanguinea) and Marphysaibaiensis sp. nov. belongs to Group E (Gravelyi). Marphysakertehensis sp. nov. is characterised by having only limbate chaetae, absence of subacicular hooks, three types of pectinate chaetae including wide, thick isodont with short and slender inner teeth, and pectinate branchiae with up to nine branchial filaments. Marphysamerchangensis sp. nov. is characterised by the presence of eyes, unidentate subacicular hooks, four types of pectinate chaetae including wide, thick anodont pectinate chaetae with five long and thick inner teeth, and pectinate branchiae with up to six branchial filaments. Marphysasetiuense sp. nov. has mostly unidentate subacicular hooks (bidentate on several posterior chaetigers), four types of pectinate chaetae including wide, thick anodont pectinate chaetae with seven thick and long inner teeth, and pectinate branchiae with up to five branchial filaments. Marphysaibaiensis sp. nov. has bidentate subacicular hooks throughout, five types of pectinate chaetae, including a heterodont with 12 short and slender inner teeth, and pectinate branchiae with up to eight branchial filaments. The designation of these new species based on morphology is fully supported by molecular data. Habitat descriptions of each species are also included.

A closer look at the taxonomic and genetic diversity of endemic South African Marphysa Quatrefages, 1865

The current study investigates the final unresolved cosmopolitan species of Marphysa in South Africa, Marphysa corallina, collected from KwaZulu Natal, Eastern and Western Cape provinces, together with another species collected from northern KwaZulu Natal. Morphological and genetic data prove that M. corallina, originally described from Hawaii, does not occur in South Africa. The curvature of the inner base on maxilla I, the elevated inner base of maxilla II, and the ventral cirrus as a transverse welt with a rounded tip allow us to identify it as a new species of Treadwellphysa, T. izinqa sp. nov. (common name: brown wonderworm). Characteristic traits include the basal reddish and distal golden colour of the subacicular hook, the ear-shaped postchaetal lobe, and tridentate falcigers which is reported for the first time for the genus. This species is harvested as bait on the south coast of SA, although less frequently than the more common blood wonderworm, Marphysa haemasona Quatrefages, 1866, and can be distinguished by its more uniform brown colouration and white-tipped antennae. A second species, Marphysa mzingazia sp. nov., is characterized by red eyes, six branchial filaments extending to the posterior end, the golden aciculae in posterior chaetigers, weakly bidentate yellow/brown subacicular hooks, and the presence of similar sized spinigers along the body. A molecular analysis based on cytochrome oxidase I fragments confirm both taxa as different species. A key for all South African species of Marphysa is included.

Sources of Polycyclic Aromatic Hydrocarbons in Fecal Pellets of a Marphysa Species (Annelida: Eunicidae) in the Yoro Tidal Flat, Japan

The fecal pellets of Marphysa sp. E sensu Abe et al. (2019) (Annelida, Eunicidae) living in the Yoro tidal flat (Ichihara, Chiba, Japan) contain high levels of polycyclic aromatic hydrocarbons (PAHs), and the concentrations rapidly decrease over time. To investigate the origin of the high-concentration PAHs in the fecal pellets and food sources of the worms, the PAH concentrations, carbon and nitrogen stable isotope ratios (δ13C and δ15N), total organic carbon, and total nitrogen for two types of sediment (sands and reduced muds), fecal pellets, and the body of the worms were determined. The PAH concentrations and chemical properties of the fecal pellets were similar to those of the reduced muds (20-30 cm sediment depth). The δ13C, δ15N, and C/N values of reduced muds were the same as the typical values of terrestrial C3 plants, suggesting that reduced muds were derived from terrestrial plants. These data indicated that the worms selectively take up reduced muds containing high levels of PAHs. The δ13C and δ15N values of the worm bodies indicated that the worms did not use the organic carbon derived from terrestrial C3 plants as primary nutrition. Taking into consideration their selective uptake of reduced muds, excretion, and subsequent rapid decrease of PAHs in the fecal pellets, the worms could contribute to the remediation of chemical pollutants in the tidal flat sediments.

Molecular and Morphological Assessment of Juvenile and Adult Forms in the Giant Worm Eunice Cf. Aphroditois (Annelida: Eunicidae) and Its Phylogenetic Position in the Family

Eunice aphroditois (Pallas, 1788) is a large polychaete worm (up to 3 m in length) and the type species of the genus. In Japan, a similar but potentially different species, Eunice cf. aphroditois, is distributed mainly in the rocky shores of the temperate and warm Pacific coasts. Juveniles and adults were suggested to be distinguished by their body color. The juvenile form was previously regarded as distinct species, Eunice flavopicta Izuka, 1912 and Eunice ovalifera Fauvel, 1936, although they are now considered synonymous with E. aphroditois. In this study, we revisited the validity of the present taxonomy based on morphological observations including SEM and microCT, and three molecular markers (cytochrome c oxidase subunit I [COI], 16S rRNA, and histone H3 genes) and investigated the phylogenetic position of E. cf. aphroditois in the family Eunicidae using the combined dataset of three genes (COI + 16S rRNA + 18S rRNA). The adult and juvenile forms were different in body size, color, the distribution of the branchiae and subacicular hooks, and maxillae shape, but not in other characteristics. One individual showed an intermediate body color between the two forms. The adult and juvenile forms shared major haplotypes and the maximum K2P genetic distance of COI was 1.7%, which can be considered within intraspecific variation. In the phylogenetic tree based on the combined gene dataset, E. cf. aphroditois was closely related to Eunice roussaei Quatrefages, 1866 and Eunice cf. violaceomaculata Ehlers, 1887, which are large species from the Mediterranean Sea and the Caribbean Sea, respectively.

Two new species of Marphysa (Annelida, Eunicidae) from southern Australia

Two new species of Marphysa Quatrefages, 1866 are described from the southeast coast of Australia. With the presence of only compound spinigers and the branchiae present over many chaetigers, Marphysa baudini n. sp. belongs to the Sanguinea-group. This species has ventral cirri with an inflated base and digitiform tip and thick and wide anodont pectinate chaetae, with 3-5 internal long and thick teeth. With the presence of only compound falcigers, Marphysa davidattenboroughi n. sp., belongs to the "Aenea-group". This species is characterised by the presence of a bilobed prostomium, a single pair of pygidial cirri and by the presence of thick, and wide anodont pectinate chaetae with 4-6 long internal and thick teeth.

A further step towards the characterisation of Terebellides (Annelida, Trichobranchidae) diversity in the Northeast Atlantic, with the description of a new species

Several new species of genus Terebellides Sars, 1835 (Annelida, Trichobranchidae) have been recently described from the Northeast Atlantic Ocean after the detection of a large complex of species based on DNA sequence data from previous research. Some of those species (belonging to the so-called Group A) have already been described elsewhere. In this paper, we revise several Terebellides clades belonging to Groups B, C and D resulting in the identification of five nominal species: Terebellidesgracilis Malm, 1874, Terebellidesatlantis Williams, 1984, Terebellideswilliamsae Jirkov, 1989, Terebellidesirinae Gagaev, 2009, and Terebellidesshetlandica Parapar, Moreira & O'Reilly, 2016, plus one new species described here as Terebellideslavesquei sp. nov. All these species are characterised by a combination of morphological features complemented with a nucleotide diagnostic approach (specific COI nucleotides in the alignment position). Morphological characters used to discriminate between taxa refer to the branchial shape, presence/absence of ciliated papillae dorsal to thoracic notopodia and the morphology of thoracic and abdominal uncinal teeth. An updated identification key to all described species of this genus in NE Atlantic waters is also included.

Three new deep-sea species of Marphysa (Annelida, Eunicida, Eunicidae) from Papua New Guinea (Bismarck and Solomon seas)

Three new species of Marphysa Quatrefages, 1866, Marphysabanana sp. nov., Marphysapapuaensis sp. nov., and Marphysazanolae sp. nov. are described from deep-sea sunken vegetation off Papua New Guinea, using both morphology and molecular data (for two species). With the presence of compound spinigers only and the branchiae present over many chaetigers, Marphysabanana sp. nov. belongs to the group B2. This species is characterised by the presence of eyes, the presence of branchiae starting from chaetiger 20, and by the presence of three types of pectinate chaetae and bidentate subacicular hooks starting from chaetigers 13-52. With the presence of compound falcigers only and the branchiae restricted to a short anterior region, Marphysapapuaensis sp. nov. belongs to the group C1. This species has a bilobed prostomium but no eyes, has branchiae from chaetigers 7 to 14-16 with up to 16 filaments. Marphysapapuaensis sp. nov. is also characterised by the presence of bidentate subacicular hooks from chaetiger 20 and by a single type of pectinate chaetae. Finally, Marphysazanolae sp. nov. belongs to the group C2, with the presence of compound falcigers only and the branchiae present over many chaetigers. This species is characterised by the absence of eyes, by the presence of branchiae with a single long filament starting from chaetiger 31, by unidentate subacicular hooks starting from chaetiger 28 and finally by one type of pectinate chaetae with very long outer teeth.

A new species of giant Eunice (Eunicidae, Polychaeta, Annelida) from the east coast of Australia

A new giant species is described from New South Wales, Australia. Eunicedharastii sp. nov. differs from described Australian species and is most similar to E.aphroditois (Pallas, 1788), E.flavopicta Izuka, 1912, and E.kinbergi Ehlers, 1868. The unique combination of features that characterizes the new species is irregular articulated prostomial appendages; antennae reaching back beyond chaetiger 4; branchiae starting at chaetiger 10, initially button-shaped and distinctly longer than notopodial cirri where best developed; dorsal fleshy knobs on anterior chaetal lobes; notopodial cirri pendulous, abrupt tapering from inflated bases; bidentate compound falcigerous chaetae with both teeth directed laterally, distal tooth much shorter than proximal tooth in median and posterior chaetigers; and dark bidentate subacicular hooks starting at chaetiger 58, tapering to a small head with both teeth directed distally, and proximal tooth much larger than minute and spur-like distal tooth. This new species lives in sandy sediments in coastal waters 1-8 m deep. It is highly mobile and not easy to collect, which may explain why it was not described before.

Reeling them in: taxonomy of marine annelids used as bait by anglers in the Western Cape Province, South Africa

Background

Common names are frequently used inconsistently for marine annelid species used as bait in the peer-reviewed literature, field guides and legislative material. The taxonomy of many such species based on morphology only also ignores cryptic divergences not yet detected. Such inconsistencies hamper effective management of marine annelids, especially as fishing for recreation and subsistence is increasing. This study investigates the scale of the problem by studying the use and names of bait marine annelids in the Western Cape Province of South Africa.

Methods

Fifteen recreational and six subsistence fishers at 12 popular fishing sites in the Western Cape Province donated 194 worms which they identified by common name. Worms were assigned scientific names according to a standard identification key for polychaetes from South Africa, and mitochondrial cytochrome oxidase I (COI) amplified and sequenced.

Results

This study identified 11 nominal species known by 10 common names, in the families Siphonosomatidae, Arenicolidae, Sabellaridae, Lumbrineridae, Eunicidae, Onuphidae and Nereididae. Cryptic diversity was investigated through employing mitochondrial COI sequences and these data will facilitate future identifications among widely distributed species. Several species (Siphonosoma dayi, Abarenicola gilchristi, Scoletoma species, Marphysa corallina, Lysidice natalensis, Heptaceras quinquedens, Perinereis latipalpa) are reported as bait for the first time, and while the names blood- and moonshineworms were consistently applied to members of Arenicolidae and Onuphidae, respectively, coralworm was applied to members of Sabellaridae and Nereididae. Analysis of COI sequences supported morphological investigations that revealed the presence of two taxonomic units each for specimens initially identified as Gunnarea gaimardi and Scoletoma tetraura according to identification keys. Similarly, sequences for Scoletoma species and Lysidice natalensis generated in this study do not match those from specimens in China and India, respectively. Further research is required to resolve the species complexes detected and also to refine the use of names by fishermen over a wider geographic range.

The Current State of Eunicida (Annelida) Systematics and Biodiversity

In this study, we analyze the current state of knowledge on extant Eunicida systematics, morphology, feeding, life history, habitat, ecology, distribution patterns, local diversity and exploitation. Eunicida is an order of Errantia annelids characterized by the presence of ventral mandibles and dorsal maxillae in a ventral muscularized pharynx. The origin of Eunicida dates back to the late Cambrian, and the peaks of jaw morphology diversity and number of families are in the Ordovician. Species richness is heterogeneous among the seven recent families, with more than half of the valid species belonging to the Eunicidae + Onuphidae clade, one of the latest clades to diverge. Eunicidans inhabit soft and hard substrates from intertidal to deep waters in all oceans. The few freshwater species are restricted to Histriobdellidae, a family exclusively commensal/parasite of crustaceans. The reproductive biology, development and ecology of most families are poorly known and the information available suggests low dispersal ability. However, all families have records of widely distributed species. Scrutiny of these wide distributions has often revealed the presence of exotic species or more than one species. The exploration of the deep-sea and of new habitats has led to recent descriptions of new species. Furthermore, the revision of type specimens, the examination of new morphological features and the use of molecular data have revealed hidden biodiversity under unjustified synonyms, poor understanding of morphological features and incomplete descriptions. Molecular studies are still very few or nonexistent for the families Histriobdellidae, Hartmaniellidae, Lumbrineridae and Oenonidae. The integration of new methodologies for morphological and molecular study, along with information on biological and ecological traits appears to be the path to improve the knowledge on the diversity of Eunicida.