Plesiomorphic Character States Research Articles

Exploring genital and pregenital musculature in Synthesiomyia nudiseta (Diptera: Muscidae: Reinwardtiinae): Insights into evolutionary relationships with subfamily Azeliinae

AbstractThe male genital, pregenital skeleton, musculature of male terminalia, and the ovipositor were studied in Synthesiomyia nudiseta (Wulp). A comparison was conducted between the terminal segments and muscles of S. nudiseta and previously studied species of the subfamily Azeliinae. Notable differences were found between previously studied species of the subfamily Azeliinae and Synthesiomyia + Muscina. These differences correspond to apomorphic character states in Synthesiomyia + Muscina, including the large size of the ejaculatory apodeme and the powerful constrictors of the ejaculatory apodeme M 23; the completely membranous sternite VI; the membrane connection of the muscle ISM 5 (lower); the small size of pregonites and postgonites; and the joints of the phallapodeme muscles М 21 at the base of the hypandrial arms. Based on these differences, Synthesiomyia + Muscina can be assigned to the subfamily Reinwardtiinae, as has been confirmed by recent molecular studies. However, similarities in the set of pregenital muscles and the set of phallapodeme muscles between Synthesiomyia + Muscina and the Azeliinae were also noted. These similarities may be considered as plesiomorphic character states, indicating their phylogenetic relationship. It can be argued that Reinwardtiinae + Azeliinae constitute sister groups and occupy the basal position within the family Muscidae.

A New Species of Ultratenuipalpus (Acari: Tenuipalpidae) from Brazil and Re-Description of Ultratenuipalpus meekeri (De Leon), the Type Species of the Genus, with DNA Barcodes.

Species of the genus Ultratenuipalpus bear a broad subquadrate propodosoma with many large, flattened, lanceolate to ovate dorsal setae. They also bear some plesiomorphic character states, such as the presence of three pairs of ventral ps setae. Here, we describe Ultratenuipalpus parameekeri Castro, Ochoa & Feres sp. nov. based on adult females, males, and immatures, collected on ferns from Brazil. We also re-describe Ultratenuipalpus meekeri (De Leon), the type species of the genus, based on types and newly collected material from Mexico, and include additional novel data (e.g., dorsal and ventral ornamentation, leg chaetotaxy, and setal measurements) in a standardized form. We include highly detailed images obtained using LT-SEM, accompanied by DNA barcodes, for both species. The ontogenetic additions of leg chaetotaxy are presented and discussed.

The earliest Pupipara (Diptera: Hippoboscoidea): A new genus and species from the lower Eocene of the Green River Formation

Eornithoica grimaldii gen. et sp. nov., the currently earliest Pupipara, is described from the lower Eocene of the Green River Formation. The previously oldest representative of this clade was from the Oligocene. The new fossil has some plesiomorphic character states, suggesting a ‘basal’ position in the clade. Its age, around 52 Ma, suggests that these epizooic ectoparasitic flies originated during the Paleocene or even the latest Cretaceous, prior to the first bats, if the latter. As is the case for several early diverging hippoboscids that feed on birds, E. grimaldii possibly victimized birds or terrestrial mammals. This study is a further example of the quantity of new information that can be obtained by the examination of fossil insects under UV light.

Musculature of the male abdominal segments and terminalia of Zaphne barbiventris (Zetterstedt, 1845) and Delia fabricii (Holmgren, 1872) (Diptera: Anthomyiidae)

AbstractThe abdominal and pregenital segments and genitalia were studied in males of Zaphne barbiventris (Zetterstedt, 1845) and Delia fabricii (Holmgren, 1872) (Anthomyiidae). The examined species are very similar in the structure of the sclerites and muscles of their terminal segments. Differences between Delia Robineau‐Desvoidy, 1830 and Zaphne Robineau‐Desvoidy, 1830 were found only in the structure of the pregenital segments and their muscles. Delia has well‐developed and well‐identified tergite VI, while tergite VI of Zaphne is fused in syntergosternite VI + VII + VIII as indicated by the insertion of muscles of ITM 5 running from tergite V. Within members of the muscoid grade, the skeleton and musculature of male terminalia of the Anthomyiidae were similar to that in the subfamily Azeliinae of the Muscidae and the Scathophagidae. The complete set of phallapodeme muscles, as well as the complete set of muscles of the pregenital sclerites and the position of cercal muscles M 26, has shown that the Anthomyiidae have more plesiomorphic character states than other members of the muscoid grade. Descriptions and figures of the terminal sclerites and muscles of Zaphne barbiventris are provided.

New dustywings of the extinct subfamily Cretaconiopteryginae (Neuroptera: Coniopterygidae) from mid-Cretaceous amber of northern Myanmar

Fossil records of the neuropteran family Coniopterygidae (dustywings) are important for understanding the phylogeny and early evolution of this highly specialized lacewing lineage. Here we describe a new genus and two new species of the extinct dustywing subfamily Cretaconiopteryginae from the mid-Cretaceous (lowermost Cenomanian) Kachin amber of northern Myanmar, namely Archaeoconis zhangzhiqiae gen et sp. nov., and Cretaconiopteryx zhengpengyueae sp. nov. These new dustywings show the basal origin of forewing RP + MA, the specialized forewing RA and RP that form a loop distally, the dense crossvenation, the zig-zagged forewing CuP, and the presence of a pair of large external male gonocoxites, which are attributed to the subfamilial diagnostic characters of Cretaconiopteryginae. Moreover, the male genitalia of Cretaconiopteryginae may represent the groundplan of the family by having a bunch of plesiomorphic character states. Our finding provides new evidence for understanding the Cretaceous diversity and early diversification of dustywings.

A new podotreme crab, Necrocarcinus christinae sp. nov., from the Woodbine Formation (Cenomanian) of Texas (USA); the first example of spermathecal apertures in a necrocarcinid brachyuran

A new necrocarcinid crab, Necrocarcinus christinae, is described from the Cenomanian deposits (Woodbine Formation) of Irving, Texas. Only a handful of decapod species are known from this formation but N. christinae sp. nov. remarkably represents the third palaeocorystoid crab. The size of the sole specimen known is much larger than usual for the genus; only the larger size of N. woodwardii is more or less comparable, and this species is morphologically most similar to this species. The closely allied genus Elektrocarcinus is reviewed and its diagnostic characters are discussed; its composition is here revised.The sole specimen of Necrocarcinus christinae sp. nov. retains a complete female thoracic sternum, with well-preserved spermathecal apertures. These are the first of such structures known from the Necrocarcinidae; they are conspicuously large compared with similar structures in other palaeocorystoid families such as Cenomanocarcinidae and Palaeocorystidae and likely represent the more basal, plesiomorphic character state. In that respect, this new material contributes to a more complete knowledge of the morphology and diversity of the extinct palaeocorystoid stock.

A new fossil leptogastrinae from the oligocene of france (diptera, asilidae)

ABSTRACT The leptogastrine Leptogaster? cerestensis sp. nov., new fossil representative of this genus, is described from the Lower Oligocene of Céreste (Southern France). This fossil shows some characters of the extant genus Mesoleptogaster but differs from it in its relatively short hind legs, a putative plesiomorphic character state, rendering its attribution to this genus uncertain.

The Phylogenetic Relationships of the Fanniidae within the Muscoid Grade (Diptera: Calyptrata) Based on the Musculature of the Male Terminalia.

Simple SummaryThe Fanniidae is a small dipteran family in the muscoid grade of the Calyptrata. To resolve controversial issues of phylogeny, in addition to molecular analyses, the study of the muscles of the pregenital and genital segments of males can significantly help because they are considered to provide important information relating to the phylogenetic branching of the Cyclorrhapha. Here, the authors report on the structure of the sclerites and the muscles of terminal segments of three species of the Fanniidae. These structures are compared with other members of the muscoid grade, as well as the Oestroidea and Hippoboscoidea. In comparison with the majority of the Calyptrata, there is a significant reduction of the sclerites and muscles of the pregenital segments of the male genitalia of the Fanniidae. The presence of the lateral bacilliform sclerites, as well as the presence and position of the epandrial muscles of the Fanniidae as in primitive Muscidae and also in Tachina and Calliphora, is best interpreted as a plesiomorphic state, while the reductions are considered as derived relative to the ground plan of the Calyptrata.The abdominal and pregenital segments and the genitalia were studied in males of Fannia subpellucens (Zetterstedt, 1845), Fannia canicularis (Linnaeus, 1761) and Fannia incisurata (Zetterstedt, 1838). In comparison with the remaining members of the muscoid grade, in addition to the symmetry of the pregenital segments, significant reductions of the sclerites and musculature of the male terminalia have been observed in Fanniidae. The muscular structure of pregenital segments confirms that the fused pregenital ring is syntergosternite VI + VII + VIII. Symmetry and fusion, as well as the lower number of the sclerites and muscles of the pregenital segments and male genitalia of the Fanniidae, can be considered apomorphic character states. The presence of the lateral bacilliform sclerite, as well as the presence and position of the epandrial muscles M 26, three pairs of muscles M 19 and paired muscles M 18, can be considered as a plesiomorphic character state of the Fanniidae. The structure of the sclerites and muscles of the male abdominal segments and terminalia place the Fanniidae at the base of the muscoid grade and Oestroidea, as has been confirmed by recent molecular studies.

Stomatal development in the cycad family Zamiaceae.

Background and AimsThe gymnosperm order Cycadales is pivotal to our understanding of seed-plant phylogeny because of its phylogenetic placement close to the root node of extant spermatophytes and its combination of both derived and plesiomorphic character states. Although widely considered a ‘living fossil’ group, extant cycads display a high degree of morphological and anatomical variation. We investigate stomatal development in Zamiaceae to evaluate variation within the order and homologies between cycads and other seed plants.MethodsLeaflets of seven species across five genera representing all major clades of Zamiaceae were examined at various stages of development using light microscopy and confocal microscopy.Key ResultsAll genera examined have lateral subsidiary cells of perigenous origin that differ from other pavement cells in mature leaflets and could have a role in stomatal physiology. Early epidermal patterning in a ‘quartet’ arrangement occurs in Ceratozamia, Zamia and Stangeria. Distal encircling cells, which are sclerified at maturity, are present in all genera except Bowenia, which shows relatively rapid elongation and differentiation of the pavement cells during leaflet development.ConclusionsStomatal structure and development in Zamiaceae highlights some traits that are plesiomorphic in seed plants, including the presence of perigenous encircling subsidiary cells, and reveals a clear difference between the developmental trajectories of cycads and Bennettitales. Our study also shows an unexpected degree of variation among subclades in the family, potentially linked to differences in leaflet development and suggesting convergent evolution in cycads.

Evolutionary morphology of the antennal heart in stick and leaf insects (Phasmatodea) and webspinners (Embioptera) (Insecta: Eukinolabia)

The morphology of the antennal hearts in the head of Phasmatodea and Embioptera was investigated with particular reference to phylogenetically relevant key taxa. The antennal circulatory organs of all examined species have the same basic construction: they consist of antennal vessels that are connected to ampullae located in the head near the antenna base. The ampullae are pulsatile due to associated muscles, but the points of attachment differ between the species studied. All examined Phasmatodea species have a Musculus (M.) interampullaris which extends between the two ampullae plus a M. ampulloaorticus that runs from the ampullae to the anterior end of the aorta; upon contraction, all these muscles dilate the lumina of both ampullae at the same time. In Embioptera, only the australembiid Metoligotoma has an M. interampullaris. All other studied webspinners instead have a M. ampullofrontalis which extends between the ampullae and the frontal region of the head capsule; these species do not have M. ampulloaorticus. Outgroup comparison indicates that an antennal heart with a M. interampullaris is the plesiomorphic character state among Embioptera and the likely ground pattern of the taxon Eukinolabia. Antennal hearts with a M. ampullofrontalis represent a derived condition that occurs among insects only in some embiopterans. These findings help to further clarify the controversially discussed internal phylogeny of webspinners by supporting the view that Australembiidae are the sister group of the remaining Embioptera.

Two centuries from species discovery to diagnostic characters: molecular and morphological evidence for narrower species limits in the widespread SW Australian Anarthria gracilis complex (Restionaceae s.l./Anarthriaceae, Poales).

BackgroundThe extreme southwest of Australia is a biodiversity hotspot region that has a Mediterranean-type climate and numerous endemic plant and animal species, many of which remain to be properly delimited. We refine species limits in Anarthria, a Western Australian endemic genus characterised by the occurrence of the greatest number of plesiomorphic character states in the restiid clade of Poales. In contrast to many other groups of wind-pollinated Australian Poales, Anarthria was traditionally viewed as having well-established species limits. All six currently recognised species, which are conspicuous members of some Western Australian plant communities, were described in the first half of the 19th century. They are traditionally distinguished from each other mainly using quantitative characters.MethodsWe examined extensive existing herbarium specimens and made new collections of Anarthria in nature. Scanning electron microscopy and light microscopy were used to study leaf micromorphology. Molecular diversity of Anarthria was examined using a plastid (trnL-F) and a low-copy nuclear marker (at103). This is the first study of species-level molecular diversity in the restiid clade using a nuclear marker.ResultsMaterial historically classified as Anarthria gracilis R.Br. actually belongs to three distinct species, A. gracilis s.str., A. grandiflora Nees and A. dioica (Steud.) C.I.Fomichev, each of which forms a well-supported clade in phylogenetic analyses. Both segregate species were described in the first half of the 19th century but not recognised as such in subsequent taxonomic accounts. Anarthria dioica was first collected in 1826, then wrongly interpreted as a species of Juncus (Juncaceae) and described as Juncus dioicus. We provide a formal transfer of the name to Anarthria and for the first time report its clear and qualitative diagnostic characters: an extremely short leaf ligule and distinctive pattern of leaf epidermal micromorphology. A long ligule is present in A. gracilis s.str. and A. grandiflora. These species differ from each other in leaf lamina morphology and anatomy and have mostly non-overlapping distribution ranges. The narrower definition of species provides a basis for future phylogeographic analyses in Anarthria. Our study highlights a need for more extensive use of nuclear DNA markers in Restionaceae. The use of the low copy nuclear marker at103 allowed a clade comprising all three ligulate species of Anarthria to be recognised. The ligule character is used here for the first time in the taxonomy of Anarthria and merits special attention in studies of other restiids. In general, our study uncovered a superficially hidden but, in reality, conspicuous diversity in a common group of wind-pollinated plants in the southwest of Western Australia.

Species Identification of Shed Snake Skins by Scanning Electron Microscopy, with Verification of Intraspecific Variations and Phylogenetic Comparative Analyses of Microdermatoglyphics

Shed skins of snakes have practical applications and can provide information on biodiversity. We examined shed skins or scales stripped from 53 native species of snakes from Taiwan and adjacent islands and 13 foreign species, verified the intraspecific variation of microstructures on the scales, conducted phylogenetic comparative analyses of microdermatoglyphics, and developed a guide and key to identify shed skins by scanning electron microscopy. We examined several microstructural characteristics of scales including the form and dimensions of oberhautchen cells, denticulations, microridges, nanopits, and nanochannels. Furthermore, we noted scale shape and presence or absence of rounded tubercles on the scales. The microstructures of apical (and central) regions of scales were similar to each other, but different from those on basal and lateral margins, the keel, or apical pits. The microdermatoglyphics on cranial scales (cephalic shields) differed from those on scales from other regions of the body. Those from the dorsal and dorsolateral surfaces of the body, and the dorsal surface of the tail were similar, as were those on scales from the ventral surfaces of the body and tail. For adults or juveniles, there was no significant ontogenetic variation in many microdermatoglyphic characteristics. By conducting phylogenetic mapping, we found that symmetrical (dorsal) scales without apical pit organs or rounded tubercles, keelless and rounded scales, flat microdermatoglyphic patterns (without longitudinal microridges), (sub)lamellate oberhautchen cells, cell borders without denticulations or with tiny and keelless denticulations, and relatively small nanopits at denticulation joints or covering cells, are likely to be plesiomorphic character states. We also examined character evolution models based on the microdermatoglyphics and their phylogenetic signals, conducted phylogenetic generalized least-squares regressions to examine the correlations among snake habitat type and the morphological traits on scales, and confirmed a hypothesis that the evolution of scale microstructures is dominated by both phylogenetic and functional (ecological) constraints. This study also indicates that scale microstructure can be used to identify snakeskin products, roadkill specimens and fragmented samples, scale remnants in predator feces, and wild snake sloughs.

New dipteromantispids (Insecta: Neuroptera: Dipteromantispidae) from mid-Cretaceous Myanmar amber

A new genus and two new species of Dipteromantispidae, an extinct raptorial family of Mantispoidea, are described from mid-Cretaceous (lowermost Cenomanian) Myanmar amber. The forewing of Paradipteromantispa polyneura gen. et sp. nov. possesses trichosors distally, bifurcate humeral veinlet, 1ma-mp connecting RP + MA and MP1, which are distinctive but probably plesiomorphic character states in Dipteromantispidae. The new genus also shares some characters with Dipteromantispa brevisubcosta Makarkin, Yang & Ren, 2013, i.e. the large body size, the medially dilated forewing costal space, and the forewing 1ma-mp distad the first branching point of MP. Kurtodipteromantispa xiai sp. nov. is separated from K. zhuodei Li & Liu, 2020 by the absence of forewing rp-ma and 2ma-mp, and the male genitalia with posterolaterally protruding tergum 9. Based on new materials with well-preserved forelegs, some fine structures on foreleg previously unknown in dipteromantispids are reported. Our finding provides new morphological evidence for understanding the placement of Dipteromantispidae in Mantispoidea.

Morphological diversity of the metathoracic spiracle in the Lygaeoidea (Hemiptera: Heteroptera)

Spiracles are the openings in the exoskeleton of insects through which air enters into the respiratory system that is formed by a series of tubes called tracheae. They are primarily located on the abdomen, but can also occur on the thorax, including the metathorax. An insect metathoracic spiracle is usually composed of an external opening and a more internal filter apparatus. We propose new terminology for these structures, and we explore the value in their use in taxonomic and phylogenetic studies within the true bug infraorder Pentatomomorpha, with emphasis on the superfamily Lygaeoidea (Insecta: Hemiptera: Heteroptera). These structures were studied using scanning electron microscopy. Two types of metathoracic spiracle external openings were recognized: a narrow opening (type N), which is slit-like; and a wide opening (type W), with internal fine structures located between the mesothoracic and metathoracic margins of the interpleural suture clearly visible. The filter apparatus in the Pentatomomorpha consists of modified mushroom bodies of the metathoracic scent gland evaporatorium, for which the term mycoid filter processes is proposed. Eight different types of mycoid filter processes, and an unmodified microsculpture type (a type with usual cuticular microsculpture) and filter setae can be found on the anterior or posterior margins of the metathoracic spiracle. We believe the wide opening (type W) to be the plesiomorphic character state in the Pentatomomorpha, with multiple, independent transformations leading to the narrow opening in Lygaeoidea. Considerable variability in the structure of the spiracle opening (in Lygaeoidea), and in the structure of the mycoid filter processes (in Pentatomomorpha) was detected. Overall, we found the morphology of these structures to be of limited value concerning the taxonomy or for determining phylogenetic relationships of the higher taxa (families) of Pentatomomorpha, but they may be useful as additional evidence for taxonomic and phylogenetic studies at the generic and perhaps the tribal levels.

New Late Jurassic Dinosaur (Ornithischia) from China Sheds Light on the Early Evolution of the Ornithopod Skeleton and Phylogeny of Ornithopoda

Numerous partial to complete individuals of a new neornithischian dinosaur have been collected from the early Late Jurassic (Oxfordian) Shishugou Formation in northwestern China. The new taxon includes an ossified clavicle and, uniquely, a patellar sesamoid and trilobate maxillary and dentary teeth. Coeval taxa from the Shaximiao Formation in Sichuan, China (Hexinlusaurus, Agilisaurus, Yandusaurus), regarded in many recent analyses as falling outside of Cerapoda (Marginocephalia + Ornithopoda), lack many characters distributed among ornithopods that are present in the new Shishugou taxon, including a large hooked coracoid process, a small quadratojugal foramen, narrow and elongate frontals, well‐developed epipophyseal ridges on the postzygapophyses of anterior cervical vertebrae, and a well‐defined and elongate femoral neck with a deep femoral capital sulcus. However, the new Shishugou taxon also retains some plesiomorphic character states relative to most ornithopods such as having five sacral vertebrae, and a short, narrow lesser trochanter on the femur. Recent analyses of neornithischian dinosaurs are not in agreement over the taxonomic composition of Ornithopoda or Cerapoda, or the distribution of characters along the neornithischian branch. Putative synapomorphies of Ornithopoda vary from study to study, as does the taxonomic composition of the clade. In some studies, many erstwhile “ornithopods” such as Thescelosaurus and Orodromeus have been pulled out of Cerapoda as basal neornithischians, while other studies recover a more inclusive monophyletic Ornithopoda. The current consensus of basal neornithischian and cerapodan phylogeny is poorly resolved. New taxa such as the Shishugou taxon that exhibit some, but not all, characters used in many studies to define Ornithopoda may help unclutter some of the resolution at the base of the cerapodan tree. The morphology present in the new taxon gives polarity to a suite of characters for basal neornithischian dinosaurs that may help provide a clearer diagnosis for Ornithopoda.Support or Funding InformationNational Science Foundation (NSF EAR 0922187, 1636753, NSF DDIG 1405834), National Geographic Society, The George Washington University, National Science Foundation of China (41120124002, 41688103)

Contribution to the taxonomy and phylogeny of the genus Polia Ochsenheimer, 1816 (Noctuidae, Noctuinae, Hadenini): species groups and pairs in the Holarctic subgenus Polia s. str.

We review the phylogenetic and biogeographical connections of the Holarctic subgenus Polia, re-considering the diagnoses of the species groups based on the external morphology and the characterisation of the male and female genitalia, as well. We produced trees based on genital morphological characters. A preliminary CO1 consensus tree was also constructed which generally supports the morphologically outlined species groups. The plesiomorphic abdominal brush organ was observed to become lost in different species groups independently. The asymmetrisation of the tufts of bristles on the saccular extensions represents one of the most important traits of the genus. These are weakly differentiated, and the shape is nearly symmetrical in supposedly plesiomorphic character states. The most differentiated asymmetrical saccular processes were found in P. serratilinea and, parallel, also in the species of the Holarctic P. nebulosa group. Holarctic connections are present in most Arctic-Boreal species and certain sister species and/or species groups in temperate taxa (i.e. in the P. bombycina and the P. nebulosa species groups), with subsequent speciation in the Nearctic. It means that Trans-Beringian migrations should have occurred at least three times in the geographical history of Polia, from which the trans-migration of the basally split P. nebulosa group was the most ancient.

Analysis of 1,000 Type-Strain Genomes Improves Taxonomic Classification of Bacteroidetes.

Although considerable progress has been made in recent years regarding the classification of bacteria assigned to the phylum Bacteroidetes, there remains a need to further clarify taxonomic relationships within a diverse assemblage that includes organisms of clinical, piscicultural, and ecological importance. Bacteroidetes classification has proved to be difficult, not least when taxonomic decisions rested heavily on interpretation of poorly resolved 16S rRNA gene trees and a limited number of phenotypic features. Here, draft genome sequences of a greatly enlarged collection of genomes of more than 1,000 Bacteroidetes and outgroup type strains were used to infer phylogenetic trees from genome-scale data using the principles drawn from phylogenetic systematics. The majority of taxa were found to be monophyletic but several orders, families and genera, including taxa proposed long ago such as Bacteroides, Cytophaga, and Flavobacterium but also quite recent taxa, as well as a few species were shown to be in need of revision. According proposals are made for the recognition of new orders, families and genera, as well as the transfer of a variety of species to other genera. In addition, emended descriptions are given for many species mainly involving information on DNA G+C content and (approximate) genome size, both of which can be considered valuable taxonomic markers. We detected many incongruities when comparing the results of the present study with existing classifications, which appear to be caused by insufficiently resolved 16S rRNA gene trees or incomplete taxon sampling. The few significant incongruities found between 16S rRNA gene and whole genome trees underline the pitfalls inherent in phylogenies based upon single gene sequences and the impediment in using ordinary bootstrapping in phylogenomic studies, particularly when combined with too narrow gene selections. While a significant degree of phylogenetic conservation was detected in all phenotypic characters investigated, the overall fit to the tree varied considerably, which is one of the probable causes of misclassifications in the past, much like the use of plesiomorphic character states as diagnostic features.

An unusual ‘shovel-billed’ dinosaur with trophic specializations from the early Campanian of Trans-Pecos Texas, and the ancestral hadrosaurian crest

We describe a new genus and species of hadrosaurid dinosaur, Aquilarhinus palimentus, from the lower shale member of the Aguja Formation (lower Campanian) of Big Bend National Park, south-western Texas. This species is characterized by several autapomorphies of the facial skeleton and mandible, including a crest composed of broadly arched nasals. Notably, the symphyseal processes of the dentary are elongated and reflected dorsally, causing the dentaries to meet with a ‘W’-shaped anterior profile. A hypothesized shovel-shaped ‘bill’, associated with widening of the skull, in A. palimentus might have been used in shovelling out and scooping up semiaquatic vegetation. This animal is otherwise superficially similar to kritosaurins like Gryposaurus but differs in the retention of key plesiomorphic character states in the maxilla and jugal. Phylogenetic analysis reveals Aquilarhinus to be a non-saurolophid hadrosaurid allied to Latirhinus from the late Campanian of Mexico, which bears a similar broadly arched nasal. The recognition of this lineage adds to the diversity of non-saurolophid hadrosaurids and points to the existence of a hitherto unknown diversity of ‘duck-billed’ dinosaurs outside of the saurolophine-lambeosaurine radiation. Cranial crests were ancestral for early hadrosaurids and evolved before the saurolophid radiation. Ancestrally, crests were ‘solid’, and consisted of arched nasals. These were retained among kritosaurins and subsequently modified into the diverse crest morphologies observed among derived saurolophines. Lambeosaurine ‘hollow-crested’ crest morphology departed from the ancestral, ‘solid-crested’ pre-saurolophid condition early following the origin of that clade.http://www.zoobank.org/urn:lsid:zoobank.org:pub:F7CE1BE7-1A76-4628-8510-93C37A1A807E

Integrated data analysis allows the establishment of a new, cosmopolitan genus of marine Macrodasyida (Gastrotricha)

Macrodasyida (phylum Gastrotricha) comprises 365 species distributed across 34 genera and 10 families. However, current classification is under revision due to the contradictory results of molecular and morphological cladistic analyses. Studies aimed at bridging the gaps took advantage of supplementary assessments of poorly known species and particularly from observations of new taxa showing original traits that could help to identify plesiomorphic character states in these anatomically diverse micrometazoa. We follow this path by describing three new interesting macrodasyidan species respectively from Italy, Brazil and Sweden. In many respects, the new species resemble most closely species of the genus Macrodasys; however, details of the external morphology, in combination with the different lay-out of the reproductive system and the tiny spermatozoa lacking a visible flagellum, suggest they belong to a new genus, possibly in the family Macrodasyidae. These hypotheses are supported by the phylogenetic relationships of 47 taxa inferred from analyses of the 18S rRNA gene, which found the new species clustering with Thaidasys tongiorgii in a subset of a larger clade containing Macrodasys. Accordingly, the establishment of the following taxa is proposed: Kryptodasys gen. nov., K. marcocurinii sp. nov., K. carlosrochai sp. nov. and K. ulfjondeliusi sp. nov.

A new species of Succinoraphidia Aspöck amp; Aspöck, 2004 (Raphidioptera: Raphidiidae) from the late Eocene Rovno amber, with venation characteristics of the genus.

Succinoraphidia radioni sp. nov. (Raphidiidae) is described from the late Eocene Rovno amber, Ukraine. The genus also includes two species from contemporaneous Baltic amber, i.e., S. exhibens Aspöck Aspöck, 2004 and S. baltica (Carpenter, 1957), comb. nov. The venation of Succinoraphidia is analysed. It possesses several plesiomorphic character states at the family level, and the monotypic subfamily Succinoraphidinae represents a basal group within the family or possibly even a potential stem group of Raphidiidae. All diagnostic character states of Succinoraphidia (except the structure of the pterostigma) are found in a few Cretaceous species of the paraphyletic Mesoraphidiidae, but some of these are not found in the extant Raphidiidae.