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Extant porpoises (Phocoenidae) are odontocetes characterized by their small size, short and wide rostrum, late (or absent) completion of epiphyseal ankylosis in the vertebral column (= physical maturity), and short life cycles, all of which are thought to have resulted from progenetic evolution. We describe a small fossil phocoenid from the lower Pliocene Koetoi Formation of Hokkaido (northern Japan), preserving a small, narrow rostrum, as well as anteroposteriorly elongate thoracic and lumbar vertebral centra with completely fused epiphyses. Physical maturity in this specimen occurred significantly earlier than in extant phocoenids, as shown by dental data indicating that the specimen died at only four years of age. The difference between the present material and extant porpoises may be attributable to different growth rates during ontogeny. The long centra and caudally inclined neural spines of the specimen from Hokkaido are primitive characters among phocoenids. By contrast, the great height of its neural spines is highly derived, even among extant species, and suggestive of a fast swimmer. In terms of its vertebral morphology, the new specimen falls within a morphological continuum defined by the archaic Numataphocoena yamashitai and the highly derived vertebral morphology of Phocoenoides dalli. Phocoenid vertebral evolution has been complex and frequently convergent, as opposed to stepwise and unidirectional. The different vertebral morphologies of the new specimen and the contemporaneous extinct taxa Numataphocoena and Piscolithax longirostris indicate that they were adapted to different environments.
Sinopachymeridium popovi, a new genus and species of fossil true bugs is described. The new species is reported from the Jiulongshan Formation (Middle Jurassic), in Daohugou Village, Shantou Town, Ningcheng County, Inner Mongolia, China. It clearly belongs to Pachymeridiidae by Sc, R and M diverging at a single point and presence costal fracture. The new genus is most similar to Pachycoridium Popov, 1986, but can be distinguished from the latter by the larger body, rostrum extending to second abdominal sternite, first vein of membrane situated remote from anterior margin of fore wing and fourth and fifth veins forming a merged vein.
Two braconid wasp taxa with enlarged eyes and ocelli indicative of probable nocturnal activity are discussed and described from the lowermost Eocene amber of the Paris Basin.The new tribe Palaeocharmontini nov., for new genus Palaeocharmon with type species Palaeocharmon basalis sp. nov. is described and illustrated in the subfamily Charmontinae. The similarity of this taxon with members of subfamilies Helconinae, Homolobinae, and Brachistinae is shown and the peculiar character [presence of hind wing recurrent vein (m−cu)] unknown previously in non−cyclostome braconids is discussed. A third fossil species of the genus Phanerotoma (Ph. menieri sp. nov.) is described and compared with known species from the Baltic amber.
Three new species Brenthorrhinoides latipecteris sp. nov., B. angustipecteris sp. nov., B. magnoculi sp. nov. within the family Nemonychidae (Coleoptera: Curculionoidea) are described and illustrated. All the fossils were recovered from the Yixian Formation (Late Jurassic or Early Cretaceous) of western Liaoning Province, China. A brief review of fossil nemonychids and a key to species within the genus Brenthorrhinoides are provided. Furthermore, possible host plants to these ancient nemonychids are discussed.
Provanna marshallisp. nov. is described from Early to Middle Miocene−age fossil hydrocarbon seep localities in the East Coast Basin, North Island, New Zealand, adding to 18 modern and three fossil species of the genus described. Modern species are well represented at hydrothermal vent sites as well as at hydrocarbon seeps and on other organic substrates in the deep sea, including sunken wood and whale falls. Described fossil Provanna species have been almost exclusively reported from hydrocarbon seep deposits, with a few reports of suspected fossil specimens of the genus from other chemosynthetic environments such as sunken wood and large vertebrate (whale and plesiosaurid) carcasses, and the oldest occurrences are dated to the Middle Cenomanian (early Late Cretaceous). The New Zealand fossil species is the most variable species of the genus described to date, and its shell microstructure is reported and found to be comparable to the fossil species Provanna antiqua and some modern species of the genus.
A new fossil lacewing, Tenuosmylus brevineurus gen. et sp. nov., was collected from an outcrop of Middle Jurassic strata in the village of Daohugou, Inner Mongolia, China. The new genus is assigned to Gumillinae based on eleven defining characteristics of the subfamily. The affiliation of Tenuosmylus including other five genera of the subfamily is discussed. Our result supports the opinion that Epiosmylinae was a junior synonym of Gumillinae, which is likely a relic of ancient osmylids based on similarity of forewing venation. Veins Mp₂ and Cu₂ have complicated branches that are generally present in extinct as well as some extant subfamilies (Poriminae, Eidoporisminae, Stenosmylinae). A key is given to differentiate six known genera within Gumillinae.
The brown frogs (Rana temporaria-group) are a monophyletic group in the family Ranidae, which have a scarce fossil record in Europe that begins only in the Late Pliocene. A new fossil from the Dietrichsberg locality (Germany, Thuringia) extends their stratigraphic range back to the Early Miocene, and suggests that their origin lies outside the Western Palaearctic, most probably in Asia, with subsequent immigration in the Burdigalian.
During the last two decades, an abundant selachian assemblage has been collected from the late Ypresian (NP12) fossiliferous sands of Prémontré (Aisne, northern France) but has received little attention. Sharks of the family Triakidae (Carcharhiniformes) are particularly well represented and all are described and figured herein. Among them, two new species of the genus Galeorhinus are described: G. duchaussoisi sp. nov. and G. louisi sp. nov.; these are compared to the common Paleogene G. ypresiensis which is refigured. Another triakid taxon, the genus Gomphogaleus gen. nov., is described. Most of the triakids have been recorded elsewhere in the North Atlantic region, suggesting a wider distribution than expected for these small sharks during the Paleogene. The present paper updates the list of selachians from Prémontré, bringing the number of taxa from 19 to 33 (including 22 sharks and 11 batoids) and improving our knowledge of the ancient North Atlantic Ypresian selachian fauna. Despite this vastly improved record, it is clear that fossil data are still very incomplete and insufficient for calibrating phylogenetic hypotheses of living forms. Review of the Prémontré fauna shows that the Triakidae were much more diverse and broadly distributed than at present, suggesting that the limited distribution and low diversity of living forms is probably a recent phenomenon.
New fossils of the family Ciconiidae from Pliocene hominid localities in Chad and Ethiopia are described, and several are shown to belong to Leptoptilos falconeri, originally known from the late Pliocene of the Siwalik Hills of India. Comparisons with all the hitherto known species of large Ciconiidae, and with an enlarged sample representing extant species, lead to a re−evaluation of some extinct taxa. Several synonymies are proposed, reflecting better the past diversity for this group. L. pliocenicus (Pliocene, Ukraine) is equivalent to L. cf. falconeri. Cryptociconia indica (late Pliocene, Siwalik Hills) belongs to Leptoptilos, and is probably either extant L. dubius or female L. falconeri. L. siwalicensis, from the same locality and also tentatively reported from the late Miocene of Northern Pakistan, is better referred to as Leptoptilini gen. et sp. indet. We consider the two following species as valid. L. titan (Pleistocene, Java) may be a late offshot of the lineage of L. falconeri. L. richae (late Miocene, Tunisia) is the size of L. crumeniferus, and is distinct from L. falconeri. Thus, L. falconeri remains the only ascertained extinct Pliocene species in the tribe Leptoptilini. It was a widespread “giant” marabou stork, in the Pliocene of southern Asia, as well as northern and eastern Africa where it coexisted with different Pliocene hominids, and probably eastern Europe. It weighed up to about 20 kg, reached 2 m in height, and had probably slightly reduced forelimbs. It became extinct by the end of the Pliocene. L. falconeri is an example of a biogeographical link at the species level between the African and Eurasian faunas in the Pliocene. The fossil record indicates the presence of at least one other lineage in Africa since the early Miocene, similar in size to the extant L. crumeniferus.
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