In a recent paper describing several new species Trapania Pruvot-Fol, 1931, a genus of dorid nudibranchs in the family Goniodorididae, one of the species named was published with two spellings of the species name. This error was introduced by copy editors after the authors had submitted the corrected proofs of the final version of the paper. Here we revise the taxonomy of this species and establish

Abstract Extant alligator lizards of the genus Abronia are found in montane cloud forests and pine-oak forests of Mesoamerica and are iconic among the public and scientific communities. Here, we describe a fossilized partial skull from the Miocene of southern California (~12.5–11.0 Mya) that is the first definitive fossil and only recognized extinct species of Abronia. The locality of the fossil is

Abstract Rhagomys is a genus of South American cricetids composed of three living species. They occur in eastern Andean and lowland tropical forests. Since description of this genus more than a century ago, it was treated as an enigmatic form within Sigmodontinae, varyingly thought to be allied to different suprageneric groups, with several scholars highlighting their presumptive autapomorphies. However

Abstract Trapania is a genus of dorid nudibranchs and one of the lesser studied members in the family Goniodorididae. Previous studies have been limited to using morphological data for producing phylogenies and establishing species relationships. This study presents the first molecular phylogeny for the genus Trapania with the goal of resolving questions that surfaced in previous morphological studies

Abstract Fish communities on tropical deep reefs are dominated by species that belong to families primarily composed of shallow-water species. Collections of deep-reef fishes via submersibles have allowed us to include these deep-reef species in molecular phylogenies, providing insights into the timing and frequency of invasions from shallow to deep reefs. Here we provide evidence of a new deep-reef

Abstract The pan-sirenian Bauplan is conservative, probably owing to the constraints of adaptation to an aquatic lifestyle. Gathering morphological data from extinct forms is complex, resulting in poorly resolved phylogenies for stem pan-sirenians. Extant sirenians ossify the falx cerebri and the tentorium cerebelli, membranes of the dura mater of the brain attached to the parietal bone. Nevertheless

Abstract The order Pleurostomatida is one of the most confusing groups in the ciliate class Litostomatea. In the present study, two new species, Paralitonotus foissneri gen. & sp. nov. and Loxophyllum apochlorelligerum sp. nov., were investigated using an integrative approach. Paralitonotus foissneri differs from other pleurostomatids by its distinctive ciliary pattern (i.e. the anterior ends of the

Abstract The genus Willisornis is endemic to the Amazon Basin, inhabiting upland terra firme forest, with two species and seven subspecies currently recognized. Despite numerous systematic studies, a taxonomically-dense sampled phylogeny for Willisornis is still lacking, which, combined with evidence of paraphyly and gene flow between its recognized species, underscores the uncertainty concerning species

Abstract As elasmobranchs are becoming increasingly threatened, efficient methods for monitoring the distribution and diversity of elasmobranch populations are required. Environmental DNA (eDNA) metabarcoding is a progressively applied technique that enables mass identification of entire communities and is an effective method for the detection of rare and elusive species. We performed an eDNA metabarcoding

Abstract Zoological narratives of intersexualities (‘hermaphroditism’), transformations of sex and same-sex sexual behaviours have long played significant roles in shaping ideas about sex more generally, for good and for bad. Eclectic references to sex-variant animals in classical and medieval texts traverse nebulous boundaries between fact and fantasy. Only slowly through the early modern era did

Abstract The Yuanmou hominid site is a rare Late Miocene fossil locality in southern China, where thousands of fossil specimens of the ape Lufengpithecus hudiensis have been found. These have been well studied, but the taxonomy of other mammalian groups is not fully understood. This is especially the case for large predator Felidae, which play a key role in the palaeo-environment in which these fossil

Abstract Nematocera (lower Diptera) is a taxonomically diverse group with ~52 000 species in 40 families, including many important agricultural and sanitary pests. The number and composition of nematoceran infraorders have long been subject to debate. The use of mitochondrial genomes for resolving these questions shows considerable promise. Herein, we sequenced and annotated the complete or nearly

Abstract Osteological knowledge of the sauropod dinosaur Ligabuesaurus leanzai is increased by the description of new postcranial elements assigned to the holotype MCF-PVPH-233. Furthermore, a newly referred specimen, MCF-PVPH-228, is recognized after a detailed revision of the abundant sauropod material collected from the Lohan Cura Formation outcrops in the Cerro de los Leones locality (southern

Abstract Bloodfeeding leeches have powerful anticoagulants that allow them to feed for extended periods. However, many leech species are predatory rather than bloodfeeding. It is not known whether they express these proteins and whether the proteins are co-opted for other purposes. Little is known about salivary secretions of the sister groups of leeches, where blood is not part of the diet. We screened

Abstract Mycteridae are a small group of Tenebrionoidea, comprising three subfamilies and over 180 species. Eurypinae are the most species-rich subfamily, with diverse external morphology of adults at both generic and species levels. To date, no study of mycterid systematics using phylogenetic approaches has been conducted. In this paper, we reconstruct a phylogeny of eurypine beetles based on morphological

Abstract Weight support is a strong functional constraint modelling limb bones in heavy quadrupeds. However, the complex relations between bone shape, mass, size and body proportions have been poorly explored. Rhinocerotoidea is one of the groups showing the highest body mass reached by terrestrial mammals through time. Here, we explore the evolutionary variation of shape in hindlimb stylopod and zeugopod

Abstract Conformity of trans-Arctic Coryphellidae genera with the most recent revised taxonomy for the group was tested. Both morphological and molecular data were used to compare more than 200 specimens from various localities in the North Pacific, North Atlantic and Arctic Oceans. The molecular study included four markers (COI, 16S, H3 and 28S) and implemented Bayesian and maximum likelihood phylogenetic

Abstract Sigurdson (1991) erected the monospecific genus Murphydoris to include the species Murphydoris singaporensis. This species differed from the rest of the genera in Goniodorididae by the lack of lamellae on the rhinophores and gill branches around the anus. Since its original description, Murphydoris singaporensis has only been found in Singapore and Thailand. Recently, the paratypes of Murphydoris

Abstract The distributional patterns of the species of the mollusc subclass Vetigastropoda were analysed using the panbiogeographical method of track analysis. We analysed distributional data of 434 species and 72 genera of the world obtained from specialized literature and records in 12 malacological collections. We constructed the individual tracks for the species analysed and superimposed them,

Abstract The investigation of species boundaries in strictly endogeic animals is challenging because they are prone to fine-scale genetic and phenotypic geographical differentiation owing to low dispersal ability. An integrative approach exploiting different sources of information has seldom been adopted in these animals and even more rarely by treating all data sources equally. We investigated species

Abstract Birds-of-paradise represent a textbook example for geographical speciation and sexual selection. Perhaps the most iconic genus is Paradisaea, which is restricted to New Guinea and a few surrounding islands. Although several species concepts have been applied in the past to disentangle the different entities within this genus, no attempt has been made so far to uncover phylogeographical patterns

Abstract Caviid rodents have peculiar craniomandibular specializations toward masticatory propalinal movements and grinding, in relation to a grass-rich diet. The aim of this study is to: (1) analyse the variation of cheek tooth shape in the Caviinae and, (2) quantify the covariation relations between caviine cheek teeth. For this purpose, we perform the first geometric morphometric analysis on cheek

Abstract The taxonomy of 185 species of Afrotropical freshwater crabs is revised to conform to the updated phylogenetic relationships within this large assemblage, based on the largest taxonomic sampling to date (that includes almost all genera and 57% of the species). Four DNA loci were sequenced including three mitochondrial loci (COI, 12S rRNA, 16S rRNA) and one nuclear locus (histone 3), and evolutionary

Abstract Brachyceran flies constitute a large radiation of the order Diptera, but the phylogenetic relationships among them have remained controversial. In this study, we used next-generation sequencing to determine mitochondrial genomes (mitogenomes) for six brachyceran flies. Two of these species represent Milichiidae (Aldrichiomyza flaviventris and Phyllomyza obliqua); two representing Chloropidae

Abstract This is the first study to combine morphological and molecular characters to infer the phylogenetic relationships among catsharks. All currently valid genera classified in the family Scyliorhinidae s.l. and representatives of other carcharhinoid families plus one lamnoid and two orectoloboids were included as terminal taxa. A total of 143 morphological characters and 44 NADH2 sequences were

Abstract The horned dinosaur genus Torosaurus has a challenging history, relating both to its geographic distribution and taxonomy. Whereas Torosaurus has been reported from Upper Maastrichtian deposits in Canada, which would mark the northernmost range of the genus, recent work has questioned the generic identity of the implicated material, which primarily consists of a pair of cranial frills. Perhaps

Abstract We investigate the species-level taxonomy and evolutionary history of Nearctic ants in the Crematogaster scutellaris group (Hymenoptera: Formicidae), drawing on evidence from morphology and UCE (ultraconserved element) phylogenomics. The New World species in this group form a well-supported clade that originated in the Late Miocene (~7.3 Mya) and subsequently diverged into three major lineages:

AbstractSplitting or lumping of species is a concern because of its potential confounding effect on comparisons of biodiversity and on conservation assessments. By comparing global lists of species reported by previous authors to lists of the presently recognized species that were known to those authors, a simple ratio can be used to describe their relative splitting or lumping of species. One group

AbstractThe Upper Jurassic Lourinhã Formation is well known for its rich assemblage of fossil vertebrates. In this formation, ornithopod dinosaurs are represented by two iguanodontian species, Eousdryosaurus nanohallucis and Draconyx loureiroi. We recently became aware of unreported material belonging to the holotype of Draconyx loureiroi, consisting of partially articulated manual elements. We here

AbstractShell features are key factors for systematics and evolutionary biology studies of freshwater gastropods. Based mostly on shell morphology, 19 species of the springsnail genus Radomaniola (family Hydrobiidae) have been described. Although the scarce differentiation of various shell dimensions suggests morphological stasis, the evolutionary dynamics of shell and other anatomical structures have

The diversity of segmented worms was gradually recognized during the 18th century and referred to a special type of animal, distinct from insects and other groups. The relationship of microdriles with earthworms was suspected, thanks to the pioneering work of Rösel, Schäffer and Müller. However, annelids could not be diagnosed correctly, nor could any reliable classification be elaborated, as long

Parvipelvia is a major clade of ichthyosaurians that diversified during the Triassic-Jurassic transition. The interrelationships of early parvipelvians remain unclear and many genera are loosely diagnosed, such as Temnodontosaurus, an ecologically important genus from the Early Jurassic of Western Europe. One taxon concentrates many taxonomic issues: ‘Ichthyosaurus’ acutirostris was previously assigned

Sea–land transition caused by marine incursion and regression is hypothesized to be a major driving force in terrestrial biodiversity, providing opportunities for marine ancestors to colonize terrestrial habitats and driving vicariant speciation in distinct geographical regions. Here, we test this hypothesis in East Asia using amphipods of the Morinoia japonica complex. We constructed a dataset from

The Tibetan antelope (Pantholops hodgsonii) is an endemic bovid of the Tibetan Plateau, which was, until recently, considered an endangered species. Researchers have long speculated on the evolutionary origin of Pantholops, suggesting a connection to the rare fossil bovid Qurliqnoria. However, the lack of adequate fossil samples has prevented the testing of this deep-time endemism hypothesis for eight

Alaria, Didelphodiplostomum and Pharyngostomoides are among genera of diplostomid digeneans known to parasitize mammalian definitive hosts. Despite numerous recent molecular phylogenetic studies of diplostomids, limited DNA sequence data is available from diplostomids parasitic in mammals. Herein, we provide the first 28S rDNA and cox1 mtDNA sequences from morphologically identified, adult specimens

In this paper we describe the new genus Aglaona, the first abyssal genus of the family Aglajidae, comprising two new species: Aglaona rudmani sp. nov. from the Sea of Okhotsk (inhabiting a depth of 3206 m) and Aglaona valdesi sp. nov. from the Pacific slope of the Kuril Islands (at a depth of 3374–3580 m). For species descriptions and inference of relationships, we have followed an integrative approach

Flea beetles (Alticini) are a diverse lineage of leaf beetles (Coleoptera: Chrysomelidae) with the majority of genera living on vascular plants. However, several genera are associated with mosses or leaf litter, as an alternative strategy, often accompanied by changes in morphology and biology. Here, we present the first comprehensive DNA-based phylogenetic analysis of Alticini including 13 moss-inhabiting

Within a few months of the year 1741, Lyonet and Trembley in Holland, Bonnet in Geneva and Réaumur in Paris all experimented industriously with the regeneration of various invertebrates, including the still unknown microdrile oligochaetes. Some of these worms were prone to spontaneous fragmentation as a natural mode of asexual multiplication, preceded (paratomy) or followed (architomy) by regenerative

The current shift of fishery efforts towards the deep sea is raising concern about the vulnerability of deep-water sharks, which are often poorly studied and characterized by problematic taxonomy. For instance, in the Mediterranean Sea the taxonomy of genus Centrophorus has not been clearly unravelled yet. Since proper identification of the species is fundamental for their correct assessment and management

The true bug infraorder Nepomorpha contains 11 families with classifications mostly using morphological features and not based on phylogenetic analyses. Presented here is the first molecular-based phylogeny for a family of Nepomorpha including more than half of the constituent taxa. Two nuclear (18S rRNA and 28S rRNA) and two mitochondrial (COI and COII) genes were used to reconstruct phylogenetic

Situated at the junction of three continents, Europe, Asia and Africa, the Eastern Mediterranean is an ideal region to study the effects of palaeogeography, ecology and long human presence on animal evolution. Laudakia stellio (Squamata: Agamidae) is found across this region and offers an excellent opportunity for such studies. The high morphological variation across their range suggests that these

Analyses of molecular data have clarified the phylogenetic relations between classes and orders of the phylum Nemertea as a whole, but the ‘deficit’ of morphological synapomorphies characterizing main clades remains problematic. Characters identified with classic histological studies of nemerteans reveal a high level of homoplasy, thus complicating the search for synapomorphies. To identify more potential

A new genus of Berothidae (Neuroptera), Speleoberotha gen. nov., with two new species from Brazil, Speleoberotha mineira sp. nov. and Speleoberotha palomae sp. nov., are herein presented. These are the first cave-associated species of Berothidae ever recorded. The new genus shares some characters with the two extant genera of the subfamily Cyrenoberothinae, Cyrenoberotha and Manselliberotha, and other

The upper dentition of Crocidura exhibits polymorphic characters that were revealed for the first time in this study via high-resolution X-ray computed microtomography. Our analyses of 11 Crocidura species and selected Diplomesodon, Suncus and Sylvisorex species from different geographical regions and size groups revealed the most complex character states of upper dentition in the Ethiopian endemic

It is generally assumed that Cretaceous stem ants were obligately eusocial, because of the presence of wingless adult females, yet the available evidence is ambiguous. Here, we report the syninclusion of a pupa and adult of a stem ant species from Mid-Cretaceous amber. As brood are immobile, the pupa was likely to have been transported by an adult. Therefore, the fossil substantiates the hypothesis

The first comprehensive molecular phylogeny of Pipunculidae (Diptera) is inferred from analyses of 6963 bp of DNA sequence data from the following five loci: cytochrome c oxidase subunit I (COI), cytochrome b (Cytb), 12S ribosomal DNA, carbamoyl phosphate synthetase region of CAD (CAD) and alanyl-tRNA synthetase (AATS). The monophyly of Pipunculidae and most known subfamilies, including Chalarinae

Hypotrichs comprise a highly differentiated and diversified group of ciliates with an evolutionary history characterized by an exceptional number of convergences and reversions. A new hypotrich ciliate from a freshwater fishpond is investigated based on morphological, morphogenetic and molecular data. The phylogenetic analyses reveal that the new species is closely related to Simplicitergida despite

The recent integrative revision of the family Macrobiotidae demonstrated monophyly of the genus Macrobiotus and its complex, mosaic morphological evolution. Here, we analyse three Macrobiotus populations that exhibit extraordinary claw morphology characterized by elongated primary branches. Two of these populations, from the Arctic, were initially classified as Macrobiotus ariekammensis, but detailed

Eumida sanguinea is a recognized polychaete species complex which, in previous studies, has been reported to have additional undescribed diversity. We detected nine additional lineages by analysing DNA sequence data (mitochondrial: COI, 16S rRNA and nuclear loci: ITS region and 28S rRNA) of E. sanguinea morphotype populations from a broader sampling effort in European marine waters. Traditional morphological

Natricine snakes are geographically widespread, species rich (with ~250 extant species) and both morphologically and ecologically diverse. We present a multilocus DNA sequence phylogeny for 249 natricine specimens representing 189 named species, including 69 specimens and 21 species not previously sampled. Our inferred Bayesian and maximum likelihood trees form the basis for evaluations of genus-level

Augochlorini comprise 646 described bee species primarily distributed in the Neotropical region. According to molecular and morphological phylogenies, the tribe is monophyletic and subdivided into seven genus groups. Our main objective is to propose a revised phylogeny of Augochlorini based on a comprehensive data set including fossil species as terminals and new characters from the internal skeleton

Five partially preserved mammaliaform petrosals recovered from Middle Jurassic sediments of the Berezovsk coal mine (Krasnoyarsk Krai, Russia) show similarities to other early mammaliaforms like the morganucodontan Morganucodon and the docodontan Haldanodon in having an inflated promontorium and a curved and apically inflated cochlear canal, but they are distinct from dryolestoid and derived mammalian

In quadrupeds, limb bones are strongly affected by functional constraints linked to weight support, but few studies have addressed the complementary effects of mass, size and body proportions on limb bone shape. During their history, Rhinocerotoidea have displayed a great diversity of body masses and relative size and proportions of limb bones, from small tapir-like forms to giant species. Here, we

Examination of material from the coasts of the Iberian Peninsula and nearby areas has revealed that more than one species is mixed under the name for the common diogenid hermit crab, Diogenes pugilator. In this study, three species are recognized, primarily on the basis of a combination of morphological characters and live colour patterns. Diogenes pugilator is redescribed on the basis of a neotype

A new genus and species of crangonyctid amphipod, Sicifera cahawba gen. & sp. nov., is described from Dallas County, AL, USA, based on both morphological and molecular comparison with similar crangonyctids. These data, with the application of four species delimitation models, identify the taxon as distinct when compared with related species. Nearctic members of the crangonyctid genus Synurella form

Phylogenetic relationships of Vestini with extensive sampling were inferred using 37 taxa scored for 66 morphological characters. Consistent with recent DNA analyses, Vesta is found to be sister to Photurinae rendering Vestini monotypic. Conversely, our parsimony and model-based analyses robustly support the new subfamily Cladodinae established for Neotropical species of the former Vestini. The cladodine

For almost 30 years, there have been active discussions about the taxonomic impediment and the challenge this represents to address the current human-induced biodiversity crisis. From the start (Systematics Agenda 2000, 1994), the term ‘taxonomic impediment’ has been ambiguous, designating both the insufficiency and inadequacy of the resources put to the service of taxonomy (the taxonomic impediment

Previous phylogenetic studies of the tribe Synergini were focused on Palaearctic material, in which the genus Synergus was recovered as monophyletic, despite evidence of non-monophyly when global sampling is considered. A global molecular phylogeny of Synergini, including sequenced material from Nearctic and Neotropical realms, is presented herein for the first time. We assembled DNA data for 120 specimens:

The genus Barbaria, recently established to accommodate the former Echiniscus bigranulatus group, is a tardigrade group emblematic for the South American tardigrade fauna. This unappendaged echiniscid lineage is widely recognized for the so-called ‘double’ sculpturing composed of endocuticular pillars and pseudopores or pores in the dorsal cuticle. The phylogenetic relationships in the genus have so