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1.
A fossil species of the extant liverwort genus Frullania Raddi is described and illustrated, based on a single inclusion in a piece of Rovno amber (Ukraine) that shares its age with Late Eocene Baltic amber, its northern contemporary. Frullania rovnoi is characterised by leaves with a rounded dorsal lobe and the absence of ocelli. The ventral lobe is inflated and forms a saclike lobule, which is bell-shaped and somewhat constricted above the mouth. The bifid underleaves have several blunt teeth or angulations along the shoulder. The Rovno fossil differs sufficiently from morphologically similar species preserved in Baltic and Bitterfeld amber as to be described as new to science. The shape of the lobules and underleaves, as well as the absence of ocelli, indicate an affiliation to F. sect. Australes, hitherto represented in Eocene amber inclusions solely by F. schumannii (Casp.) Grolle. The Rovno fossil is distinguished from extant species of F. subg. Australes and from F. schumannii by having roughly and irregularly dentate-angulate underleaf margins.  相似文献   

2.
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.  相似文献   

3.
The first fossil bumble bee (Apinae: Bombini) from the Miocene Randeck Maar of southwestern Germany is described and illustrated. The specimen is subjected to a geometric morphometric analysis along with a diversity of other bumble bee species representing most major extant lineages, and particularly the subgenus Bombus s.s. The morphometric analysis supports the placement of the Randeck Maar species within Bombus s.s., as a species distinct from all others in the subgenus. It shows that extant subgenera of bumblebees were already derived in the early/middle Miocene. The Randeck Maar fossil is formally described as Bombus (Bombus) randeckensis Wappler & Engel sp. n. .  相似文献   

4.
The organic chemical profiles of fossil Acer and Quercus leaf tissues are presented and correlated with those of previously described fossil Celtis, Ulmus and Zelkova and interpreted in conjunction with referable extant genera. Intrageneric comparisons among fossil and extant taxa indicate that relatively minor phytochemical differences exist suggesting that little flavonoid and steroid evolution since post-Miocene times has occurred. Biosystematic relationships between living North American and Asian genera indicate that in some cases (Quercus, Zelkova) a greater affinity exists between living Asiatic species and elements of the Succor Creek Flora. The chemical data are proposed as an independent parameter in assessing angiosperm biogeography and proposed migration patterns of the Fagaceae and Ulmaceae. The high chemical fidelity seen between some living and fossil genera preserved in ash-fall deposits is ascribed to the reaction of membrane bound lipids with various organic acids and to subsequent rapid dehydration.  相似文献   

5.
The endocranial anatomy of Pygoscelis calderensis, a fossil species from the Bahía Inglesa Formation (Middle Miocene–Pliocene) of Chile, South America, was described through CT scans. Reconstructions of the fossil P. calderensis and endocasts for the living Pygoscelis adeliae, and Pygoscelis papua are provided here for the first time. Comparisons with the extant congeneric species P. adeliae, Pygoscelisantarctica and P. papua indicate that the morphological pattern of the brain and inner ear of the extant pygoscelids has been present already in the Middle Miocene. The neurological morphology suggests that the paleobiology of the extinct form would have been similar to the extant species. It was probably true for diet, feeding behaviour and diving kinematics.  相似文献   

6.
Philopotinae are hunchbacked spider flies represented by 63 fossil and extant species in 15 genera worldwide. Philopota Wiedemann, 1830, is the most species‐rich genus within the subfamily. Here, the evolution of Philopotinae is discussed, and a revision and phylogeny of Philopota based on adult morphology are presented. Nine of the 12 extant Philopotinae genera were included in our analysis, and 22 species were recognized in Philopota, of which 13 are described as new. Seven new synonymies are proposed. The phylogenetic analysis included 33 terminal taxa (22 ingroup and 11 outgroup species) and used 53 morphological characters, resulting in a single most parsimonious tree under equal weights. The monophyly of Philopota is recovered, and the Palaearctic genus Oligoneura is hypothesized as its sister‐group.  相似文献   

7.
The investigation of the habitats, the spicular skeletons, and the structure and chemistry of the nonspicular high-Mg calcite skeletons of a fossil Acanthochaetetes from the Late Albian (Cretaceous) of Northern Spain and the extant Acanthochaetetes wellsi from Pacific reefs demonstrates an astonishing correspondence. The skeletons of both species are hemispherical or pyriform with the lower part containing an epitheca. They are built up of single calicles which are subdivided by tabulae. Spines protrude from the walls into the calicles. Scanning electron microscopy and thin sections reveal that the high-Mg calcite skeleton consists of two different microstructures: a irregular ssensu Wendt 1979 or microlamellar (sensu Cuif et al. 1979) and a completely irregular structure. AAS and EDAX analysis of the calcite skeletons produce roughly the same Mg and Sr contents. Tylostyle megascleres and aster-like microscleres are observed in the spicular skeletons of both species. The only difference between the two species is the greater variability of the microscleres in the extant species. Moreover, the fossil species incorporates the scleres in the non-spicular skeleton, while the extant species does not. Both species live/lived in the same niches of tropical reefs: the cryptic habitats of submarine caves in the reef core and the dimly lighted habitats of the deeper fore-reef.  相似文献   

8.
A new fossil species of crane-fly, Helius botswanensis:Diptera: Tipulidaey is described. The specimen was discovered recently in reliably dated. Cretaceous sediments from Botswana. Ii is extremely well preserved, has a distinctive morphology, and is identified as belonging to the extant genus Helius. The single specimen puts the origin of the subfamily Limoniinae and the genus well into the Cretaceous Period, and provides data on the southern African Cretaceous palaeoenvironment. The conservative nature of a dipteran of such antiquity, assignable to an extant genus which has an association with flowers, has implications for evolutionary theory.  相似文献   

9.
Fossil fruits and a vegetative axis assignable to the extant genus Ceratophyllum are described from four North American Tertiary localities. Fossil fruits assignable to the extant species C. muricatum and C. echinatum are reported from the Eocene Green River and Claiborne formations, and the Miocene Esmerelda Formation, respectively. An extinct species, C. furcatispinum, is described from the Paleocene Fort Union Formation and represents the oldest published report of Ceratophyllum in the fossil record. The existence of extant angiosperm species in the Eocene is very unusual and may be attributable in this case to slow evolutionary rates and unusual evolutionary properties associated with hydrophily in the genus Ceratophyllum.  相似文献   

10.
A new spider species of the extant genus Craspedisia Simon (Araneae: Theridiidae) is described from a fossil in Miocene amber from the Dominican Republic. X-ray computed tomography (CT) was used to reveal important features that were impossible to view using traditional microscopy, because of the position in which the spider is preserved. Craspedisia yapchoontecki sp. nov. is the first described fossil species from this genus and has its closest relative among the extant Hispaniolan fauna.  相似文献   

11.
Fossil spinicaudatan taxonomy heavily relies on carapace features (size, shape, ornamentation) and palaeontologists have greatly refined methods to study and describe carapace variability. Whether carapace features alone are sufficient for distinguishing between species of a single genus has remained untested. In our study, we tested common palaeontological methods on 481 individuals of the extant Australian genus Ozestheria that have been previously assigned to ten species based on genetic analysis. All species are morphologically distinct based on geometric morphometrics (p ≤ 0.001), but they occupy overlapping regions in Ozestheria morphospace. Linear discriminant analysis of Fourier shape coefficients reaches a mean model performance of 93.8% correctly classified individuals over all possible 45 pairwise species comparisons. This can be further increased by combining the size and shape datasets. Nine of the ten examined species are clearly sexually dimorphic but male and female morphologies strongly overlap within species with little influence on model performance. Ornamentation is commonly species-diagnostic; seven ornamentation types are distinguished of which six are species-specific while one is shared by four species. A transformation of main ornamental features (e.g. from punctate to smooth) can occur among closely related species suggesting short evolutionary timescales. Our overall results support the taxonomic value of carapace features, which should also receive greater attention in the taxonomy of extant species. The extensive variation in carapace shape and ornamentation is noteworthy and several species would probably have been assigned to different genera or families if these had been fossils, bearing implications for the systematics of fossil Spinicaudata.  相似文献   

12.
A total evidence phylogenetic analysis was performed for 14 extant and 18 fossil caniform genera using a data matrix of 5.6 kbp of concatenated sequence data from six independent loci and 80 morphological characters from the cranium and dentition. Maximum parsimony analysis recovered a single most parsimonious cladogram (MPC). The topology of the extant taxa in the MPC agreed with previous molecular phylogenies. Phylogenetic positions for fossil taxa indicate that several taxa previously described as early members of extant families (e.g., Bathygale and Plesictis) are likely stem taxa at the base of the Arctoidea. Taxa in the “Paleomustelidae” were found to be paraphyletic, but a monophyletic Oligobuninae was recovered within this set of taxa. This clade was closely related to the extant genera Gulo and Martes, therefore, nested within the extant radiation of the family Mustelidae. This analysis provides a resolution to several discrepancies between phylogenies considering either fossil taxa or extant taxa separately, and provides a framework for incorporating fossil and extant taxa into comprehensive combined evidence analyses.  相似文献   

13.
A Fagus-like leaf fossil (cuticular compression) with an attached fruit, differing from any known Fagus species (fossil or extant) or other fagoid taxa, has been discovered from the Miocene Clarkia Lake deposits of northern Idaho. Because of its unusual morphology (especially the fruit) the fossil taxon has been described as a new genus and species, Pseudofagus idahoensis Smiley and Huggins. The successful previous use of paleobiochemistry in studies of fossil taxa from the Miocene Succor Creek Flora of Oregon suggested that chemical data might help clarify the taxonomic affinities of Pseudofagus. Indeed, examination of the chemistry of the fossil, Pseudofagus idahoensis, and comparison with extant Fagus species and related fagoid genera indicate that: 1) based on steroid chemistry, Pseudofagus idahonesis does belong in the Fagaceae; 2) like all extant species of Fagus, the fossil lacks the tannin component, ellagic acid, which separates it from other extant fagoid genera, and 3) its simple flavonoid pigment profile places it closest to the extant North American Fagus grandifolia or the European/Eurasian Fagus sylvatica. However, the exclusive presence of an isorhamnetin (3'-methoxyquercetin) 3-0-glycoside, onocerane, and 5α-cholestane imparts a species-specific chemical character to Pseudofagus idahoensis, which also sets it apart from extant species of Fagus. While the chemistry does not decide the taxonomic level to be accorded to the fossil, it certainly supports, along with morphology and anatomy, the distinctness of Pseudofagus and its proposed relationships within the Fagaceae.  相似文献   

14.
A fossil Mycetophilidae from the Aptian Crato Formation—Cretomanota gondwanica gen. nov., sp. nov.—is described, which is the first mycetophilid from the Crato Formation and corresponds to the oldest known fossil leiine and only the second Gondwanan fossil mycetophilid described so far. Cretomanota gondwanica and both species of Alavamanota Blagoderov and Arillo were added as terminals to the data matrix of a general phylogenetic analysis of the Mycetophilidae, and both fit into the Leiinae. Alavamanota is monophyletic, sister to the clade composed by Cretomanota and the extant genus Manota Williston. The biology of the extant members of this fungivorous family corroborates the reconstruction of the Crato palaeoenvironment as including woodlands with humid habitats and microhabitats. The presence of a Cretaceous member of the tribe Manotini at low latitudes in South America reinforces the hypothesis that the clade with all manotines except Leiella Edwards corresponds to a Lower Cretaceous offshoot from a group in southern Gondwana expanding its distribution to more northern areas into the Gondwana and into Laurasia.  相似文献   

15.
《Annales de Paléontologie》2017,103(2):113-125
The first known fossil specimens of pipehorses (Haliichthyinae) were unearthed from the Middle Miocene (Sarmatian) beds of the Coprolitic Horizon in the Tunjice Hills, Slovenia. These fossil pipehorses belong to a new genus and species Hippohaliichthys edis, which was similar to the extant species Haliichthys taeniophorus. The body morphology indicates that the described fossil pipehorses were also closely related to the pygmy pipehorse Hippotropiscis frenki and the seahorse Hippocampus sarmaticus, two taxa which were also found in the Coprolitic Horizon. The described fossil material of pipehorses indicates that seahorses evolved from a group of pipehorses that were similar in size and shape to extant and fossil pipehorses of the Haliichthyinae subfamily.  相似文献   

16.
Abstract: The fossil record of the callianassid genus Glypturus (Decapoda, Axiidea) is re‐evaluated. Our systematic revision, both of extant and fossil taxa, is based on major cheliped morphology only, thus providing an important impetus for palaeontological studies. Both spination and tuberculation of chelipeds are herein considered of great taxonomic importance. Presence of spines on the upper margins of the merus and propodus and the lower margin of the carpus are significant for generic assignment, whereas the extent of tuberculation on lateral surfaces of the propodus is important for assignment at the species level. Altogether, four extant and six exclusively fossil species of Glypturus are recognized. Several extinct callianassid taxa are now transferred to the genus, namely Callianassa berryi, Callianassa fraasi, Callianassa munieri, Callianassa pugnax and Callianassaspinosa; Callianassa pseudofraasi is considered a junior synonym of C. fraasi. Based on a comparison of ecological preferences of extant representatives, the presence of Glypturus in the fossil record is considered to be linked with tropical to subtropical, nearshore carbonate environments of normal salinity. We argue that Glypturus is of Tethyan origin, with a stratigraphical range going as far back as the Eocene. Since then, the genus migrated both westwards and eastwards, establishing present‐day communities in the western Atlantic and Indo‐West Pacific which both comprise several distinct species. In the presumed area of origin, the genus does no longer occur today. The exlusively fossil (middle Eocene) genus Eoglypturus from Italy is considered closely related to Glypturus and is thus assigned to the subfamily Callichirinae as well.  相似文献   

17.
GERALD MAYR 《Ibis》2009,151(2):392-395
A tarsometatarsus of a diminutive representative of the Phalacrocoracoidea, the clade including the Phalacrocoracidae (cormorants) and Anhingidae (anhingas), is described from the early Miocene of Germany. The fossil is assigned to a new species Limicorallus (?) carbunculus, and closely resembles the tarsometatarsus of extant Phalacrocoracidae in overall morphology. Limicorallus (?) carbunculus is the smallest representative of the Phalacrocoracoidea, reaching only two‐thirds the size of the extant Pygmy Cormorant Phalacrocorax pygmeus. By significantly lowering the minimum size of the Phalacrocoracoidea, this new species adds to our knowledge of the early diversity of this clade.  相似文献   

18.
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.  相似文献   

19.
Six new fossils of Micromalthus (Coleoptera: Archostemata) from Dominican amber are compared with extant and previously described fossil micromalthid beetles. The amber inclusions are well preserved and all important morphological features are visible. Taking into account the morphological variability of the extant species Micromalthus debilis LeConte, 1878 , it is not possible to find any morphological features that distinguish the fossils from the extant species. This also applies to the Dominican amber inclusion described as Micromalthus anasi Perkovsky, 2008, which therefore is considered a junior synonym of M. debilis. The lack of morphological change in M. debilis over time might possibly be explained by unusually stable environmental conditions, as this species occupies a very specialized ecological niche in decaying timber. A general survey of fossil insects indistinguishable from extant species is presented. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 300–311.  相似文献   

20.
Fossil angiospermous stamens with in situ pollen from the Turonian (ca. 90 million years before present, Late Cretaceous) of New Jersey are described and assigned to the Chloranthaceae. The fossil stamens, which are three-parted and bear two bisporangiate thecae on the central lobe and one bisporangiate theca on each lateral lobe, are indistinguishable from stamens of several extant species of Chloranthus. The pollen is spheroidal, 13–18 μm in diameter, with a reticulate exine and apparently elongate/elliptical apertures. The pollen is similar to that in extant Chloranthus in grain size, shape, exine sculpture, and aperture structure. Like pollen of some extant species of Chloranthus, aperture number in the fossil pollen appears to be variable. Because fossil pistillate chloranthoid reproductive structures have not been found at this locality it is unknown whether the fossil stamens described here were borne on the side of the ovary, as in extant Chloranthus, or in another arrangement. The three-parted stamen of Chloranthus is unique in angiosperms and there has been considerable debate concerning the origin and evolutionary significance of the structure. Uncertainty as to whether the three-parted stamen represents a synapomorphy for the genus or a retained plesiomorphy in angiosperms is the primary reason why these fossil stamens are not assigned to the extant genus Chloranthus.  相似文献   

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