New information and family relationship (Hymenophyllaceae) for the fossil fern genus Acrostichopteris Fontaine and a new species from the Lower Cretaceous (Albian) of Spain

PREMISE

Reinvestigation of previously described fossil plants using improved techniques can provide insights for additional characters resulting in better family assignments and relationships to modern plants, as in this new study of the fossil fern Acrostichopteris from the mid-Cretaceous. The discovery of new species within genera provides additional characteristics for comparisons and support for family assignments.

METHODS

Fossil material was uncovered from the matrix (degagement) for the specimens described here. Material was removed from the matrix and mounted for examination by scanning electron microscopy (SEM). Spores were extracted and prepared for examination with light, fluorescence, and SEM. Characters for the previously described material from the Potomac Group in the USA and the new material from Spain were compared with those of other fossils assigned to the genus.

RESULTS

The genus, described by Fontaine in 1889, reexamined by Berry in 1911, and assigned to the Schizaeaceae by Reed in 1947, is reassigned to the family Hymenophyllaceae on the basis of characteristics of the pinnules, sori, sporangia, and spores. We describe a new species in the genus from the Lower Cretaceous (Albian) of Spain that most likely belongs in this family, based on characteristics of the pinnules and the sori. A summary of all the species previously assigned to the genus is included.

CONCLUSIONS

Assignment of this fossil to the family Hymenophyllaceae is based on all characters known and comparison to modern species, provides the time for appearance of characteristics within the family, and indicates diversification of Hymenophyllum species in the mid-Cretaceous.

A braconid wasp (Hymenoptera, Braconidae) from the Lower Cretaceous amber of San Just, eastern Iberian Peninsula

Braconid parasitoid wasps are a widely diversified group today, while their fossil record from the Mesozoic is currently poorly known. Here, we describe Utrillabraconelectropteron Álvarez-Parra & Engel, gen. et sp. nov., from the upper Albian (Lower Cretaceous) amber of San Just in the eastern Iberian Peninsula. The holotype specimen is incomplete, although the forewing and hind wing venation are well preserved. The new taxon is assigned to the subfamily †Protorhyssalinae (Braconidae) and, based on characteristics of the wing venation, seems to be closely related to Protorhyssalusgoldmani Basibuyuk & Quicke, 1999 and Diorhyssalusallani (Brues, 1937), both from Upper Cretaceous ambers of North America. We discuss the taxonomy of the Cretaceous braconids, considering †Seneciobraconinae as a valid subfamily. We also comment on possible relationships within †Protorhyssalinae, although a phylogenetic analysis is necessary. Additionally, a checklist is included of braconids known from Cretaceous ambers.

Rhinochelys amaberti Moret (1935), a protostegid turtle from the Early Cretaceous of France

Modern marine turtles (chelonioids) are the remnants of an ancient radiation that roots in the Cretaceous. The oldest members of that radiation are first recorded from the Early Cretaceous and a series of species are known from the Albian-Cenomanian interval, many of which have been allocated to the widespread but poorly defined genus Rhinochelys, possibly concealing the diversity and the evolution of early marine turtles. In order to better understand the radiation of chelonioids, we redescribe the holotype and assess the taxonomy of Rhinochelys amaberti Moret (1935) (UJF-ID.11167) from the Late Albian (Stoliczkaia dispar Zone) of the Vallon de la Fauge (Isère, France). We also make preliminary assessments of the phylogenetic relationships of Chelonioidea using two updated datasets that widely sample Cretaceous taxa, especially Rhinochelys. Rhinochelys amaberti is a valid taxon that is supported by eight autapomorphies; an emended diagnosisis proposed. Our phylogenetic analyses suggest that Rhinochelys could be polyphyletic, but constraining it as a monophyletic entity does not produce trees that are significantly less parsimonious. Moreover, support values and stratigraphic congruence indexes are fairly low for the recovered typologies, suggesting that missing data still strongly affect our understanding of the Cretaceous diversification of sea turtles.

An exquisitely preserved filmy fern (Hymenophyllaceae) from the Early Cretaceous of Mongolia

PREMISE OF THE STUDY

Hymenophyllaceae ("filmy ferns") are a widely distributed group of predominantly tropical, epiphytic ferns that also include some temperate and terrestrial species. Hymenophyllaceae are one of the earliest-diverging lineages within leptosporangiate ferns, but their fossil record is sparse, most likely because of their low fossilization potential and commonly poor preservation of their delicate, membranaceous fronds. A new species of unequivocal fossil Hymenophyllaceae, Hymenophyllum iwatsukii sp. nov., is described from the Early Cretaceous of Mongolia based on abundant and exceptionally well-preserved material.

METHODS

Bulk lignite samples collected from Tevshiin Govi and Tugrug localities in Mongolia, were disaggregated in water, cleaned with hydrochloric and hydrofluoric acids, washed, and dried in air. Fossils were examined and compared to material of extant Hymenophyllaceae using LM and SEM.

KEY RESULTS

The fossil fern specimens are assigned to the Hymenophyllaceae based on their membranaceous laminae with marginal sori that have sessile to short-stalked sporangia with oblique, complete annuli, and trilete, tetrahedral-globose spores. Within the family, the fossil material is assigned to the extant genus Hymenophyllum on the basis of bivalvate indusia and short, included receptacles.

CONCLUSIONS

Hymenophyllum iwatsukii was likely an epiphyte based on the sedimentary environment in which the fossils are preserved, the associated fossil flora, and the growth habit of extant species of Hymenophyllum. The new fossil species underlines the extent to which morphological characters in Hymenophyllum have been conserved despite significant tectonic, climatic, ecological, and floristic changes since the Early Cretaceous.

An enigmatic crocodyliform tooth from the bauxites of western Hungary suggests hidden mesoeucrocodylian diversity in the Early Cretaceous European archipelago

Background. The Cretaceous of southern Europe was characterized by an archipelago setting with faunas of mixed composition of endemic, Laurasian and Gondwanan elements. However, little is known about the relative timing of these faunal influences. The Lower Cretaceous of East-Central Europe holds a great promise for understanding the biogeographic history of Cretaceous European biotas because of the former proximity of the area to Gondwana (as part of the Apulian microcontinent). However, East-Central European vertebrates are typically poorly known from this time period. Here, we report on a ziphodont crocodyliform tooth discovered in the Lower Cretaceous (Albian) Alsópere Bauxite Formation of Olaszfalu, western Hungary.

Methods. The morphology of the tooth is described and compared with that of other similar Cretaceous crocodyliforms.

Results. Based on the triangular, slightly distally curved, constricted and labiolingually flattened crown, the small, subequal-sized true serrations on the carinae mesially and distally, the longitudinal fluting labially, and the extended shelves along the carinae lingually the tooth is most similar to some peirosaurid, non-baurusuchian sebecosuchian, and uruguaysuchid notosuchians. In addition, the paralligatorid Wannchampsus also possesses similar anterior teeth, thus the Hungarian tooth is referred here to Mesoeucrocodylia indet.

Discussion. Supposing a notosuchian affinity, this tooth is the earliest occurrence of the group in Europe and one of the earliest in Laurasia. In case of a paralligatorid relationship the Hungarian tooth would represent their first European record, further expanding their cosmopolitan distribution. In any case, the ziphodont tooth from the Albian bauxite deposit of western Hungary belongs to a group still unknown from the Early Cretaceous European archipelago and therefore implies a hidden diversity of crocodyliforms in the area.

Early Cretaceous araucarian driftwood from hemipelagic sediments of the Puez area, South Tyrol, Italy

We describe a calcareously permineralised fossil tree-trunk, preserved as driftwood, within hemipelagic sediments of the Cretaceous Puez Formation near Wolkenstein, South Tyrol, Italy. Planktic foraminiferal assemblages recovered from the marls containing the fossil wood indicate a latest middle Albian age. Based on its wood anatomy, the trunk is assigned to Agathoxylon and probably has an affinity with the conifer family Araucariaceae. The wood lacks pronounced tree-rings consistent with tree growth within the broad humid tropical belt that existed at that time. The trunk contains cylindrical chambers filled within faecal pellets, demonstrating that oribatid mites infested the tree, either during life, or shortly after death. Prior to final burial, the tree-trunk drifted out into the open sea for a considerable period as indicated by extensive borings assigned to the ichnospecies Teredolites longissimus and produced by teredinid bivalves. Relatively little is known about the Cretaceous floras of Italy, so this new finding fills a gap in our knowledge of the composition and ecology of the vegetation of this region.

Snakefly diversity in Early Cretaceous amber from Spain (Neuropterida, Raphidioptera)

The Albian amber from Spain presently harbors the greatest number and diversity of amber adult fossil snakeflies (Raphidioptera). Within Baissopteridae, Baissoptera? cretaceoelectrasp. n., from the Peñacerrada I outcrop (Moraza, Burgos), is the first amber inclusion belonging to the family and described from western Eurasia, thus substantially expanding the paleogeographical range of the family formerly known from the Cretaceous of Brazil and eastern Asia. Within the family Mesoraphidiidae, Necroraphidia arcuatagen. et sp. n. and Amarantoraphidia ventolinagen. et sp. n. are described from the El Soplao outcrop (Rábago, Cantabria), whereas Styporaphidia? hispanicasp. n. and Alavaraphidia imperterritagen. et sp. n. are describedfrom Peñacerrada I. In addition, three morphospecies are recognized from fragmentary remains. The following combinations are restored: Yanoraphidia gaoi Ren, 1995, stat. rest., Mesoraphidia durlstonensis Jepson, Coram and Jarzembowski, 2009, stat. rest., and Mesoraphidia heteroneura Ren, 1997, stat. rest. The singularity of this rich paleodiversity could be due to the paleogeographic isolation of the Iberian territory and also the prevalence of wildfires during the Cretaceous.

New earwigs in mid-Cretaceous amber from Myanmar (Dermaptera, Neodermaptera)

Two new earwigs (Dermaptera) recently discovered in mid-Cretaceous (latest Albian) amber from Myanmar are described and figured. Astreptolabis ethirosomatiagen. et sp. n. is represented by a peculiar pygidicranoid female, assigned to a new subfamily, Astreptolabidinaesubfam. n., and differs from other protodermapterans in the structure of the head, pronotum, tegmina, and cercal forceps. Tytthodiplatys mecynocercusgen. et sp. n. is a distinctive form of first-instar nymph of the Diplatyidae, the earliest record for this basal earwig family. The taxon can be distinguished from other Early Cretaceous nymphs by the structure of the head, antennae, legs, and most notably its filamentous and annulate cerci. The character affinities of these taxa among Neodermaptera are generally discussed as is the identity of an enigmatic ‘earwig-like’ species from the Jurassic of China.

New and revised maimetshid wasps from Cretaceous ambers (Hymenoptera, Maimetshidae)

New material of the wasp family Maimetshidae (Apocrita) is presented from four Cretaceous amber deposits – the Neocomian of Lebanon, the Early Albian of Spain, the latest Albian/earliest Cenomanian of France, and the Campanian of Canada. The new record from Canadian Cretaceous amber extends the temporal and paleogeographical range of the family. New material from France is assignable to Guyotemaimetsha enigmatica Perrichot et al. including the first females for the species, while a series of males and females from Spain are described and figured as Iberomaimetsha Ortega-Blanco, Perrichot & Engel, gen. n., with the two new species Iberomaimetsha rasnitsyni Ortega-Blanco, Perrichot & Engel, sp. n. and Iberomaimetsha nihtmara Ortega-Blanco, Delclòs & Engel, sp. n.; a single female from Lebanon is described and figured as Ahiromaimetsha najlae Perrichot, Azar, Nel & Engel, gen. et sp. n., and a single male from Canada is described and figured as Ahstemiam cellula McKellar & Engel, gen. et sp. n. The taxa are compared with other maimetshids, a key to genera and species is given, and brief comments made on the family.