Descriptions and phylogenetic relationships of a new genus and two new species of Oligo‐Miocene cormorants (Aves: Phalacrocoracidae) from Australia

Tertiary cormorant fossils (Aves: Phalacrocoracidae) from Late Oligocene deposits in Australia are described. They derive from the Late Oligocene – Early Miocene (26–24 Mya) Etadunna and Namba Formations in the Lake Eyre and Lake Frome Basins, South Australia, respectively. A new genus, Nambashag gen. nov. , with two new species ( Nambashag billerooensis sp. nov. , 30 specimens; Nambashag microglaucus sp. nov. , 14 specimens), has been established. Phylogenetic analyses based on 113 morphological and two integumentary characters indicated that Nambashag is the sister taxon to the Early Miocene Nectornis miocaenus of Europe and all extant phalacrocoracids. As Nambashag, Nectornis, and extant phalacrocoracids constitute a strongly supported clade sister to Anhinga species, the fossil taxa have been referred to Phalacrocoracidae. Sulids and Fregata were successive sister taxa to the Phalacrocoracoidea, i.e. phalacrocoracids + Anhinga. As phalacrocoracids lived in both Europe and Australia during the Late Oligocene and no older phalacrocoracid taxa are known, the biogeographical origin of cormorants remains unanswered. The phylogenetic relationships of extant taxa were not wholly resolved, but contrary to previous morphological analyses, considerable concordance was found with relationships recovered by recent molecular analyses. Microcarbo is sister to all other extant phalacrocoracids, and all Leucocarbo species form a well‐supported clade. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 277–314.     

First record of a tarsometatarsus of Tonsala hildegardae (Plotopteridae) and other avian remains from the late Eocene/early Oligocene of Washington State (USA)

New bird fossils from the late Eocene/early Oligocene Makah Formation and the Oligocene Pysht Formation on the Olympic Peninsula (Washington State, USA) are described. A partial skeleton from the Pysht Formation includes the first reported tarsometatarsus of Tonsala hildegardae Olson, 1980, a wing-propelled diving bird of the taxon Plotopteridae. It shows that Tonsala had a tarsometatarsus that was morphologically intermediate between that of the late Eocene Phocavis and more derived plotopterids. We introduce the new taxon Tonsalinae nov. subfam. for a clade including all named plotopterids except Phocavis, Plotopterum, and the recently described Stemec. We furthermore describe a partial plotopterid pelvis and a sternum from the Makah Formation. The sternum shows a close resemblance to that of extant Phalacrocoracoidea (cormorants and darters) and may be the earliest North American record of this taxon.     

A fossil heron from the early Oligocene of Belgium: the earliest temporally well‐constrained record of the Ardeidae

We describe the earliest temporally well‐constrained fossil that can be assigned to the Ardeidae (herons), from the lowermost Oligocene (32.0–33.0 million years ago) of Belgium. The specimen, a partial tarsometatarsus, belongs to a small species and is described as Proardea? deschutteri n. sp. It exhibits the characteristic tarsometatarsus morphology found in extant heron species, but a confident assignment to one of the ardeid subclades is not possible and even the assignment of the new fossil species to the crown group (the clade including the extant species) cannot be established. The fossil indicates a divergence of herons from their sister taxon by at least the earliest Oligocene, and current paleontological data suggest that herons arrived in Europe shortly after a major faunal turnover at the Eocene/Oligocene boundary. We consider that dispersal is the likely reason for the sudden appearance of herons in the earliest Oligocene of Europe but it is uncertain from where exactly this took place, with Asia and Africa being among the candidate areas.     

A Pelican Tarsometatarsus (Aves: Pelecanidae) from the Latest Pliocene Siwaliks of India

We report a new fossil specimen of a pelican from the Tatrot Formation of the Siwalik Hills, India. It likely represents Pelecanus sivalensis Davies, 1880, the smaller of the two previously published species from the Siwalik Group stratigraphic sequence. This complete tarsometatarsus is the first fossil bone of a pelican collected in India for over 100 years. It is from the latest Pliocene (∼2.6 Ma), and is the youngest pelican fossil from the region. The new specimen exhibits a derived distoplantar ‘slant’ to the plantar margin of the medial crest of the hypotarsus, and a combination of features related to the morphology of the hypotarsus, the distal foramen, trochleae, and overall size that allow further differentiation from known tarsometatarsi of fossil and extant pelicans, including the three species of extant pelicans that occur in India (Pelecanus crispus, P. onocrotalus, and P. philippensis). It is of appropriate size for Pelecanus sivalensis, which to date has been known only by fragments of other skeletal elements of the wing, leg, and shoulder girdle. Thus, the observation that this tarsometatarsus is morphologically distinct from those of known pelicans provides further support for the distinctiveness of at least one extinct species of pelican from the Siwalik Group sediments. While the morphology of the tarsometatarsus allows for separation from other taxa known from tarsometatarsi, we found no clear shared derived states to place this taxon with any confidence in a phylogenetic context relative to any other pelican species, or even determine if it is part of the crown group of Pelecanidae. However, published molecular data are consistent with an origin of the crown clade prior to the Pleistocene, suggesting (along with one morphological character) the possibility that this species belongs to the Old World clade of pelican species.     

A tiny stem group representative of Pici (Aves, Piciformes) from the early Oligocene of the Czech Republic

We describe a new stem group representative of Pici (woodpeckers, honeyguides, barbets, and allies) from the early Oligocene (Rupelian) of the Czech Republic. The holotype of Picavus litencicensis, gen. et sp. nov. is a postcranial skeleton with well-preserved feather remains. The new species is distinguished from crown group Pici in several plesiomorphic features and is assigned to the new taxon Picavidae, fam. nov. The absence of an elongated accessory trochlea for the reversed fourth toe shows P. litencicensis to be the most basal representative of Pici, and concerning the morphology of the distal tarsometatarsus the species represents a morphological link between Pici and their sister taxon, the Galbulae. Like all other early Oligocene piciform birds, P. litencicensis is a tiny bird, the size of the smallest extant Pici. Because all Palaeogene Pici were found in Europe and some of these are outside the crown group, an Old World origin of Pici is likely. With definitive crown group representatives of Pici being unknown before the late Oligocene/early Miocene, the fossil record does not support earlier molecular calibrations, which resulted in a late Cretaceous divergence of crown group Pici.     

Earliest fossil record of the Certhioidea (treecreepers and allies) from the early Miocene of Germany

A complete tarsometatarsus of a passerine bird from the early Miocene (MN 3) of Petersbuch (Bavaria, Germany) is identified as an extinct representative of the climbing Certhioidea, i.e., a clade comprising treecreepers (Certhiidae), nuthatches and wallcreepers (Sittidae). The fossil specimen represents the so far earliest evidence of a representative of the Certhioidea and is described as †Certhiops rummeli gen. et sp. nov. Similarities to other climbing passerines are discussed.     

Tachypteron franzeni n. gen., n. sp., earliest emballonurid bat from the Middle Eocene of Messel (Mammalia, Chiroptera)

A new genus and species of emballonurid microchiropteran,Tachypteron franzeni, is described from the early Middle Eocene (MP 11) of Grube Messel, near Darmstadt, Germany. The holotype is extraordinarily well-preserved. It is the first unequivocal representative of an extant clade among Messel bats and the oldest unequivocal record of Emballonuridae. The flight apparatus ofT. franzeni is highly specialized for a rapid and constant flight style. The proportions of the strikingly narrow wing, the outline of the flight membranes and external ear, the morphology of the postcranial skeleton, and the relative cochlea size ofT. franzeni and extantTaphozous species are almost identical, while the dentition ofT. franzeni is distinguished by more plesiomorphic features.Tachypteron and the fairly diverse Paleogene record of emballonurids from France, consisting mainly of isolated teeth, document the earliest radiation known from an extant bat family and suggest a rather intense pre-Middle Eocene diversification of emballonurids.     

Locomotory abilities and habitat of the Cretaceous bird Gansus yumenensis inferred from limb length proportions

The relative length proportions of the three bony elements of the pelvic (femur, tibiotarsus and tarsometatarsus) and pectoral (humerus, ulna and manus) limbs of the early Cretaceous bird Gansus yumenensis, a well‐represented basal ornithuromorph from China, are investigated and compared to those of extant taxa. Ternary plots show that the pectoral limb length proportions of Gansus are most similar to Apodiformes (swifts and hummingbirds), which plot away from all other extant birds. In contrast, the pelvic limb length proportions of Gansus fall within the extant bird cluster and show similarities with the neornithine families Podicipedidae (grebes), Diomedeidae (albatross) and Phalacrocoracidae (cormorants). Although it does have some of the pelvic limb features of grebes and cormorants, the femur of Gansus is more gracile and is thus more consistent with an albatross‐like shallow‐diving mode of life than a strong foot‐propelled diving movement pattern. The position of Gansus in pectoral limb ternary morphospace is largely due to its elongated manus. In contrast to apodiformes, where the humerus and ulna are short and robust, an adaptation, which provides a stiff wing for their demanding fast agile and hovering flight (respectively), the wing‐bones of Gansus are slender, indicating a less vigorous flapping flight style. The suite of characters exhibited by Gansus mean it is difficult to completely interpret its likely ecology. Nevertheless, our analyses suggest that it is probable that this bird was both volant and capable of diving to some degree using either foot‐propelled or, perhaps, both its wings and its feet for underwater locomotion.     

A reassessment of Eocene parrotlike fossils indicates a previously undetected radiation of zygodactyl stem group representatives of passerines (Passeriformes)

In the past years, various Eocene fossil birds were described as stem group representatives of the zygodactyl Psittaciformes (parrots). These birds show quite disparate morphologies, which cast some doubt on the correct assignment of all of them to the psittaciform stem group. A reassessment of their affinities is further needed, because it was recently proposed that among extant birds, Psittaciformes and Passeriformes (passerines) form a clade and that passerines possibly derived from a zygodactyl ancestor. Here, phylogenetic analyses are performed, which for the first time also include representatives of the Zygodactylidae, the extinct zygodactyl sister taxon of the Passeriformes. The early Eocene Psittacopes was originally described as a stem group representative of Psittaciformes. However, none of the present analyses supported psittaciform affinities for Psittacopes and instead recovered this taxon in a clade together with zygodactylids and passerines. Also part of this clade are the early Eocene taxa Pumiliornis and Morsoravis, and it is detailed that Psittacopes and the long‐beaked and presumably nectarivorous Pumiliornis, with which it has not yet been compared, are very similar in their postcranial osteology. The present analysis corroborates the hypothesis of a zygodactyl stem species of passerines. To account for these results, Psittacopes is here assigned to a new higher‐level taxon and a new name is also introduced for the clade including Zygodactylidae and Passeriformes.     

Systematics and evolutionary significance of the small Abrocomidae from the early Miocene of southern South America

Octodontoidea is the most species-rich clade among hystricomorph rodents, and has a fossil record going back to at least the late Oligocene. Affinities of fossils previous to the late Miocene differentiation of the extant families Abrocomidae, Echimyidae and Octodontidae are controversial, essentially because these fossils may share few apomorphies with modern species. In fact, pre-late Miocene representatives of Abrocomidae had not been recognised until very recently. Here we revise the early Miocene genus Acarechimys, originally assigned to Echimyidae, and alternatively to stem Octodontoidea or to Octodontidae. A systematic and parsimony-based phylogenetic analysis of the species traditionally included in Acarechimys showed that this genus is part of stem Abrocomidae. These results are primarily supported by morphology of the mandible and lower molars. Acarechimys is here restricted to three species, A. minutus, A. pulchellus and Acarechimys pascuali sp. nov., while another species, A. constans, is here transferred to a new abrocomid genus. The remaining species were nested within Octodontidae. According to these results, Abrocomidae might have been as diverse as its sister clade Octodontidae-Echimyidae during the late Oligocene–early Miocene. Extinction of this diversity would have resulted in marked loss of evolutionary history, with extant abrocomids being currently restricted to late-diverged euhypsodont representatives.     

Systematics,phylogeny and evolutionary pattern of the hystricognath rodent Eumysops (Echimyidae) from the Plio–Pleistocene of southern South America

?Eumysops is a peculiar representative of the currently tropical family Echimyidae, which evolved in increasingly dry and cold Plio–Pleistocene environments of southern South America. The results of a systematic and stratigraphic review of the genus, and of phylogenetic analyses based on both morphology and a combined morphological–molecular dataset in the context of extant representatives, are presented here. Recognised diversity includes four previously described species plus a new one from the late Pliocene. These species form a well-supported monophyletic clade, sister to the late Miocene ?Pampamys and the extant Thrichomys. The position of ?Eumysops–?Pampamys–Thrichomys in a major clade including non-‘eumysopine’ echimyids constrains the traditional taxon Eumysopinae only to these three genera. Phylogeny and stratigraphic distribution of ?Eumysops species suggest an essentially cladogenetic evolutionary pattern. Beyond this, a gradual directional change, involving increase in size and in molar hypsodonty, is shown by ?Eumysops chapalmalensis as part of a late Pliocene faunal turnover interpreted as a local representation of the 2.5-Ma cooling global event. Distinctive skeletal and dental anatomy of ?Eumysops, including large orbits, shortened braincase, marked hypsodonty and postcranial specialisations, would be a result of its southern history related to a particular palaeoclimatic context.     

Systematics and evolution of the Pan‐Alcidae (Aves,Charadriiformes)

Puffins, auks and their allies in the wing‐propelled diving seabird clade Pan‐Alcidae (Charadriiformes) have been proposed to be key pelagic indicators of faunal shifts in Northern Hemisphere oceans. However, most previous phylogenetic analyses of the clade have focused only on the 23 extant alcid species. Here we undertake a combined phylogenetic analysis of all previously published molecular sequence data (～ 12 kb) and morphological data (n = 353 characters) with dense species level sampling that also includes 28 extinct taxa. We present a new estimate of the patterns of diversification in the clade based on divergence time estimates that include a previously vetted set of twelve fossil calibrations. The resultant time trees are also used in the evaluation of previously hypothesized paleoclimatic drivers of pan‐alcid evolution. Our divergence dating results estimate the split of Alcidae from its sister taxon Stercorariidae during the late Eocene (～ 35 Ma), an evolutionary hypothesis for clade origination that agrees with the fossil record and that does not require the inference of extensive ghost lineages. The extant dovekie Alle alle is identified as the sole extant member of a clade including four extinct Miocene species. Furthermore, whereas an Uria + Alle clade has been previously recovered from molecular analyses, the extinct diversity of closely related Miocepphus species yields morphological support for this clade. Our results suggest that extant alcid diversity is a function of Miocene diversification and differential extinction at the Pliocene–Pleistocene boundary. The relative timing of the Middle Miocene climatic optimum and the Pliocene–Pleistocene climatic transition and major diversification and extinction events in Pan‐Alcidae, respectively, are consistent with a potential link between major paleoclimatic events and pan‐alcid cladogenesis.     

Combined phylogenetic analysis of a new North American fossil species confirms widespread Eocene distribution for stem rollers (Aves,Coracii)

We report a nearly complete skeleton of a new species of stem roller (Aves, Coracii) from the early Eocene Green River Formation of North America. The new species is most closely related to two species‐depauperate lineages, Coraciidae (rollers) and Brachypteraciidae (ground rollers), that form a monophyletic crown clade (Coracioidea) with an exclusively Old World extant distribution. Phylogenetic analysis utilizing a matrix of 133 morphological characters and sequence data from three genes (RAG‐1, c‐myc, and ND2) identifies the new species as a stem member of the Coracii more closely related to the crown clade than the only previously identified New World taxon, Primobucco mcgrewi. The phylogenetic placement of the new species and Primobucco mcgrewiindicates a widespread northern hemisphere distribution in the Eocene with subsequent restriction to Africa, Madagascar, Australia, and temperate to tropical parts of Europe and Asia. It provides evidence of further ecological diversity in early stem Coracii and convergence on crown morphologies. The new species contributes to mounting evidence that extant distributions for major avian subclades may be of comparatively recent origin. Further late Palaeogene sampling is needed to elucidate potential drivers for shifting avian distributions and disappearance of Coracii from North America. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 157 , 586–611.     

Monogenoidean parasites of the gill lamellae of the sheepshead Archosargus probatocephalus (Walbaum) (Perciformes: Sparidae) from the Indian River Lagoon, Florida, with descriptions of four new species of Euryhaliotrema Kritsky & Boeger, 2002 (Dactylogyridae)

Examination of the gill lamellae of three sheepshead Archosargus probatocephalus (Walbaum) from the Indian River Lagoon in Florida revealed six species of Monogenoidea: Microcotyle archosargi MacCallum, 1913 (Microcotylidae); Neobenedenia sp. (Capsalidae); and four new species of Euryhaliotrema Kritsky & Boeger, 2002 (Dactylogyridae). The prevalence of all helminths was 100%, except for Neobenedenia sp., which was represented by a single immature specimen. The four new species, Euryhaliotrema carbuncularium n. sp., E. dunlapae n. sp., E. amydrum n. sp. and E. spirulum n. sp., are described and with E. carbunculus (Hargis, 1955) Kritsky & Boeger, 2002 apparently constitute a monophyletic clade of Euryhaliotrema spp. that parasitise sparid hosts in the western hemisphere. The Indian River Lagoon in Florida represents a new locality record for M. archosargi, and the sheepshead is apparently a new host record for a member (Neobenedenia sp.) of the Capsalidae.     

Etelis boweni sp. nov., a new cryptic deepwater eteline snapper from the Indo-Pacific (Perciformes: Lutjanidae)

A new species of Etelis is described based on 16 specimens collected from the Red Sea and Western Australia, with confirmed genetic records throughout the Indo-West Pacific. It is similar to and was often misidentified as Etelis carbunculus Cuvier, with both species sharing the diagnostic character of low number of developed gill rakers. Nonetheless, the two species are genetically divergent and differ morphologically in adult body length; proportions of eye, snout, cheek and caudal fin; shape of head, opercular spine and sagittal otolith; and coloration of the tip of the upper caudal fin. Etelis boweni has a wide Indo-west Pacific distribution that largely overlaps with E. carbunculus, and the two species are often caught on the same fishing line.     

A new large philisid (Mammalia,Chiroptera, Vespertilionoidea) from the late Early Eocene of Chambi,Tunisia

Abstract: Among the new dental remains from the late Early Eocene of Chambi (Kasserine area, Tunisia) is a large‐sized upper molar of a new bat species, Witwatia sigei nov. sp. (Chiroptera, Vespertilionoidea, Philisidae), described herein. The locality of Chambi has revealed evidence for an early appearance of two modern microchiropteran superfamilies in Africa: Dizzya exsultans, a Philisidae, which is considered to be an archaic Vespertilionoidea, and an indeterminate Rhinolophoidea. In addition to D. exsultans, the new species, W. sigei, is the second representative of the Philisidae in this locality. W. sigei extends back to the late Early Eocene the occurrence of the genus Witwatia, which was previously only reported from the early Late Eocene of the Fayum (BQ‐2, Egypt). By analogy with the largest extant microbats, the large size of Witwatia suggests a tendency to the opportunistic diet of this taxon, thereby contrasting with the strict insectivory characterizing primitive bats found in other continents in the same epoch.     

Gobekko cretacicus (Reptilia: Squamata) and its bearing on the interpretation of gekkotan affinities

Gobekko cretacicus, a Cretaceous lizard from the Gobi Desert of Mongolia, is a key fossil for understanding gecko phylogeny. We revisit this fossil using high‐resolution X‐ray computed tomography. The application of this imaging method reveals new information about sutures, bone shape, and structural details of the palate and basicranium. These data were used to assess the phylogenetic affinities of Gobekko in the context of an existing squamate data set. The effects of character ordering, search strategy, and the addition of another putative gekkonomorph (Hoburogekko suchanovi) on inferred gekkonomorph relationships were explored. Available specimens of G. cretacicus are skeletally mature but have unfused nasals, frontals, and parietals, and (possibly) a persistent basicranial fenestra. Some putative gekkonomorphs are not consistently supported as closer to crown clade gekkotans than to autarchoglossans. In a strict consensus both Gobekko and Hoburogekko form a polytomy with extant geckos. Some of the adult character states of Gobekko are observable in embryos of extant species. The evolution of tubular frontals and dentaries in gekkotans may be structurally related to the loss of the postorbital and supratemporal bars in this lineage. The complete lack of a parietal foramen, and presumably a light‐sensitive parietal eye, in this clade is of interest and could indicate an early origin of nocturnality in geckos. © 2013 The Linnean Society of London     

A scolopocryptopid centipede (Chilopoda: Scolopendromorpha) from Mexican amber: synchrotron microtomography and phylogenetic placement using a combined morphological and molecular data set

The first scolopocryptopid centipede known from the fossil record is a specimen of the subfamily Scolopocryptopinae in Miocene amber from Chiapas, southern Mexico. It is described here as Scolopocryptops simojovelensis sp. nov. , displaying a distinct combination of morphological characters compared to extant congeners. Anatomical details of the fossil specimen were acquired by non‐invasive 3D synchrotron microtomography using X‐ray phase contrast. The phylogenetic position of the new species is inferred based on a combination of morphological data with sequences for six genes (nuclear 18S and 28S rRNA, nuclear protein‐coding histone H3, and mitochondrial 12S rRNA, 16S rRNA, and protein‐coding cytochrome c oxidase subunit I) for extant Scolopendromorpha. The data set includes eight extant species of Scolopocryptops and Dinocryptops from North America, east Asia, and the Pacific, rooted with novel sequence data for other blind scolopendromorphs. The molecular and combined data sets, analysed in a parsimony/direct optimization framework, identified a stable pattern of two main clades within Scolopocryptopinae. North American and Asian species of Scolopocryptops are united as a clade supported by both morphological and molecular characters. Its sister group is a Neotropical clade in which the type species of Dinocryptops is nested within a paraphyletic assemblage of Scolopocryptops species; Dinocryptops is placed in synonymy with Scolopocryptops. The strength of support for the relationships of extant taxa from the molecular data allow the Chiapas fossil to be assigned with precision, despite ambiguity in the morphological data; the fossil is resolved as sister species to the extant Laurasian clade. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 768–786.     

Macrosiagon deuvei n. sp. (Coleoptera: Ripiphoridae) from the French Eocene amber

Macrosiagon deuvei n. sp., the second fossil representative of this extant genus of Ripiphoridae: Ripiphorinae: Macrosiagonini is described from the lowermost Eocene amber of Oise (France). The new species is compared with the extant species of the genus. Taxonomic position of other two fossil representatives of the family described from France by Perrichot et al. (2004) is discussed. The genus Paleoripiphorus Perrichot et al. 2004 is tentatively transferred from Ripiphorinae to Ripidiinae.     

On the phylogenetic position and systematics of extant and fossil Aclopinae (Coleoptera: Scarabaeidae)

The Aclopinae is a small subfamily within the family Scarabaeidae. It currently comprises five extant genera with 28 species, and eight fossil genera with 25 species. The systematic position of Aclopinae within the family Scarabaeidae is uncertain, particularly because representative species of Aclopinae have been absent in previous phylogenetic studies. Here we performed phylogenetic analyses using morphological and molecular data to investigate the phylogenetic position of fossil and extant Aclopinae. For this objective, we expanded and revised a former morphological data matrix (composed of 68 characters) including all extant genera of Aclopinae. We complemented our morphological investigations with a molecular phylogenetic analysis based on four genes of several extant taxa of Aclopinae and a wide sample of diverse Scarabaeoidea. Our phylogenetic analyses show that all the type species of the fossil genera formerly included within Aclopinae do not belong within the extant Aclopinae clade and support both the exclusion of those fossil taxa and the monophyly of the extant genera of Aclopinae: Aclopus Erichson, Desertaclopus Ocampo & Mondaca, Gracilaclopus Ocampo & Mondaca, Neophanaeognatha Allsopp and Phanaeognatha Hope. Our results also show that the fossil taxa Prophaenognatha robusta Bai et al. and Ceafornotensis archratiras Woolley are closely related to Ochodaeidae, while the remaining type species of fossils formerly included in Aclopinae (Cretaclopus longipes (Ponomarenko), Holcorobeus vittatus Nikritin, Juraclopus rodhendorfi Nikolajev, Mesaclopus mongolicus (Nikolajev), and Mongolrobeus zherikhini Nikolajev) belong to a distinct lineage closely related to Diphyllostomatidae. Based on these results, the subfamily Aclopinae appears monophyletic and sister to the ‘pleurostict’ lineage. Consequently, we propose the following changes to the current classification of the fossil taxa: Holcorobeus monreali (Gómez‐Pallerola) belongs to Carabidae (incertae sedis) as proposed by the original author, and we place Ceafornotensis Woolley, Cretaclopus Nikolajev, Holcorobeus Nikritin, Juraclopus Nikolajev, Mesaclopus Nikolajev, Mongolrobeus Nikolajev and Prophaenognatha Bai et al. in Scarabaeoidea (incertae sedis). Furthermore, we provide an identification key to, and diagnoses of, the genera, illustrations of diagnostic characters and checklists of their included species. The evolutionary perspective presented provides new insights into the evolution of the pleurostict condition in Scarabaeoidea and the biogeography of this group, which is now regarded as Gondwanan, probably evolving during the Cretaceous and not from the upper Jurassic as previously assumed.