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1

Nebraskophis Holman from the Late Eocene of Georgia [USA], the oldest known North American colubrid snake

100%

Parmley D. , Holman J. A.

Acta Zoologica Cracoviensia

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2003

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tom 46

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nr 1

EN

An extinct colubrid snake of the genus Nebraskophis is reported on the basis of a trunk vertebra from the Late Eocene (36.0-34.2 Ma) of central Georgia, USA. The fossil represents the oldest record of the family Colubridae in North America, and is equivalent to, or slightly older in age than the previously oldest known colubrid remains from the Late Eocene of Thailand. The age and remarkable similarity of the fossil to living colubrid vertebrae suggest that the origin of colubrid snakes considerably predates the Late Eocene. The presence of Nebraskophis in Georgia supports the hypothesis of an early Cenozoic biogeographic connection between the Great Plains and southeastern region of the United States for at least some early colubrids. The genus probably evolved autochthonously on the continent rather than arriving as a Eurasian immigrant.

2

New species of the extinct ant genus Stigmomyrmex Mayr and designation of the neotype of Stiphromyrmex robustus (Mayr) (Hymenoptera: Formicidae: Myrmicinae)

80%

Radchenko A. , Dlussky G. M.

Annales Zoologici

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2017

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tom 67

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nr 4

EN

The extinct ant genera Stigmomyrmex Mayr and Stiphromyrmex Wheeler (subfamily Myrmicinae) were described from the Baltic amber (Late Eocene, Priabonian, ca. 34-38 Ma). A new species, Stigmomyrmex rugulosus sp. nov., is described from the Baltic and Bitterfeld ambers, and a neotype of Stiphromyrmex robustus (Mayr) is designated. Additionally, we found from the Bitterfeld amber three more specimens of S. venustus Mayr, previously the only known species of the genus. S. rugulosus well differs from S. venustus by the presence of longitudinal rugulosity on the head dorsum, mesosoma and waist, and by the presence of numerous suberect hairs on the legs.

3

Boltonidris gen. nov., the first extinct Stenammini ant genus (Hymenoptera, Formicidae) from the Late Eocene Rovno amber

80%

Radchenko A. , Dlussky G. M.

Annales Zoologici

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2012

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tom 62

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nr 4

EN

The new extinct ant genus and species, Boltonidris mirabilis, are described from the late Eocene Rovno Amber (Ukraine). This genus belongs to the tribe Stenammini of the subfamily Myrmicinae. It possesses the plesiomorphic characters of the tribe Stenammini, e.g. 12-segmented antennae with 3-segmented apical club, characteristic structure of the clypeus and frontal lobes, absence of gastral shoulder, but it has a series of autapomorphies, e.g. modified mandibles with the only two teeth on the masticatory margin, well developed longitudinal medial groove on the head dorsum, somewhat depressed areas lateral to the frontal carinae (like "vestigial" antennal scrobes), and finely swollen postero-lateral area of head, close to the occipital corners. Additionally, it has two short blunt teeth on the pronotum.

4

Catshark egg capsules from a Late Eocene deep-water methane-seep deposit in western Washington State, USA

80%

Kiel S. , Peckmann J. , Simon K.

Acta Palaeontologica Polonica

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2013

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tom 58

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nr 1

EN

Fossil catshark egg capsules, Scyliorhinotheca goederti gen. et sp. nov., are reported from a Late Eocene deep−water methane−seep calcareous deposit in western Washington State, USA. The capsules are preserved three−dimensionally and some show mineralized remnants of the ribbed capsule wall consisting of small globular crystals that are embedded in a microsparitic matrix. The globules are calcitic, but a strontium content of 2400–3000 ppm suggests that they were origi− nally aragonitic. The carbonate enclosing the egg capsules, and the capsule wall itself, show 13C values as low as −36.5‰, suggesting that formation was induced by the anaerobic oxidation of methane and hence in an anoxic environ− ment. We put forward the following scenario for the mineralization of the capsule wall: (i) the collagenous capsules expe− rienced a sudden change from oxic to anoxic conditions favouring an increase of alkalinity; (ii) this led to the precipitation of aragonitic globules within the collagenous capsule wall; (iii) subsequently the remaining capsule wall was mineralized by calcite or aragonite; (iv) finally the aragonitic parts of the wall recrystallized to calcite. The unusual globular habit of the early carbonate precipitates apparently represents a taphonomic feature, resulting from mineralization mediated by an organic matrix. Taphonomic processes, however, are at best contributed to an increase of alkalinity, which was mostly driven by methane oxidation at the ancient seep site.

5

Priabonian, late Eocene chronostratigraphy, depositional environment, and paleosol-trace fossil associations, Pipestone Springs, southwest Montana, USA

80%

Hanneman D. L. , Lofgren D. , Hasiotis S. T. , McIntosh W. C.

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tom 67

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nr 1

6

A new ant genus from the late Eocene European amber

80%

Dlussky G. , Radchenko A.

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2006

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tom 51

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nr 3

EN

Eocenomyrma gen. nov. of extinct ants of the family Formicidae, subfamily Myrmicinae, is described from the late Eocene European amber (ca. 40 Ma), based on six specimens from six pieces of amber; three of them contain E. rugosostriata (Baltic and Saxonian ambers); the remainder contain three new species: E. orthospina (Baltic Amber), E. electrina (Scandinavian Amber), and E. elegantula (Baltic Amber). Eocenomyrma resembles two extant genera: Myrmica and Temnothorax (both of which also occur in late Eocene European amber), but differs from them by the following apomorphies: clypeus short and broad, with two lateral longitudinal carinae and distinctly marked anterolateral corners, its median portion faintly concave transversally, anterior margin broad and shallowly concave medially, with pairs of long setae situated on the anterolateral clypeal corners, and central part of the anterior clypeal margin without setae; middle and hind tibiae lacking the spurs. Palp formula in Eocenomyrma is 4, 3 versus 6, 4 in Myrmica. We include Eocenomyrma in the tribe Formicoxenini. Nothomyrmica rugosostriata is transferred to Eocenomyrma, and the neotype of the latter species is designated; Nothomyrmica petiolata is transferred to the genus Temnothorax. A key for the identification of all known Eocenomyrma species is compiled.

7

The Late Eocene evolution of nummulitid foraminifer Spiroclypeus in the Western Tethys

80%

Less G. , Ozcan E.

Acta Palaeontologica Polonica

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2008

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tom 53

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nr 2

EN

Megalospheric forms of Priabonian Spiroclypeus of the Western Tethys were morphometrically investigated. Based on the reduction of the average number of undivided, post−embryonic chambers, the investigated populations are grouped into two successive, phylogenetically linked species, S. sirottii sp. nov. and S. carpaticus. The evolution is also demonstrated by the increase of the number of secondary chamberlets in particular chambers, by the increase of the diameter of the first two whorls and by that of the size of the proloculus, although the latter turned out to be also ecologically controlled. This evolution is supported by the stratigraphic succession of populations in the Mossano section (N Italy) and by the change of accompanying fossils. Lacking in upper Bartonian beds, the first appearance of genus Spiroclypeus seems to be synchronous with the beginning of the late Eocene. The newly described S. sirottii is associated with Heterostegina reticulata mossanensis and orthophragmines containing forms of middle Eocene acme, both marking the lower part of the Priabonian. Meanwhile S. carpaticus co−occurs with H. gracilis and/or with orthophragmines characteristic of the upper part of the Priabonian. We suppose that the Spiroclypeus sirottii–carpaticus lineage is restricted to the Priabonian. Thus, Spiroclypeus sirottii is a zonal marker for the Shallow Benthic Zone (SBZ) 19 (early Priabonian) while S. carpaticusindicates the SBZ 20 (late Priabonian).

8

A new talpid from the late Eocene of North America

80%

Lloyd K. J. , Eberle J. J.

Acta Palaeontologica Polonica

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2008

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tom 53

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nr 3

EN

The origin and early evolution of talpids (moles, shrew−moles, and desmans) is not well understood, in large part due to the poor fossil record of early talpids. Here we report the oldest known talpid from North America, Oreotalpa florissantensis gen. et sp. nov., based upon a tiny dentary with m1–m3 discovered in upper Eocene (Chadronian) strata of the Florissant Formation, Florissant Fossil Beds National Monument, Colorado. Oreotalpa extends the North American record of talpids back by some six Ma and appears temporally correlative with the oldest documented talpids from the late Eocene of Europe. While others have postulated a Eurasian origin for talpids, discovery of Oreotalpa suggests that the evolution of the group was underway in North America by late Eocene time and raises the possibility of a North American origin.

9

Remarks on palaeoenvironmental changes based on reviewed Tertiary insect associations from the Krusne hory piedmont basin and the Ceske stredohori Mts in Northwestern Bohemia [Czech Republic]

80%

Prokop J.

Acta Zoologica Cracoviensia

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2003

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tom 46

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nr Suppl.

EN

Cenozoic insect fauna of northwestern Bohemia is preserved in fluviolacustrine deposits of the Krušné hory piedmont basins and the České středohoří Mts. The fossil insect assemblages are correlated with palaeobotanical results. The local palaeoenvironmental conditions such as the distance from the shoreline or water depth are interpreted. A reflection of changes in distribution of fossil entomofaunas is compared with relevant world localities of different palaeoenvironments. The sparse fossil insect taphocoenoses fill a gap in record of significant diverse non-marine invertebrate communities and serve for reconstruction of terrestrial palaeoecosystems. The selected fossil sites demonstrate insect taphocoenoses formed under conditions of the palaeoenvironment of a diatomaceous lake with subtropical forests (Kučlín), lowlands of riparian and mesophytic forests (Kundratice - Seifhennersdorf), warm-temperate swamp to riparian forests (Bílina mine) and lake sedimentation near mixed mesophytic forests (Mokřina). The aim is to compare fossil entomofaunas from several periods within Tertiary in northwestern Bohemia and search for analogous palaeoenvironmental conditions in other areas. The results are correlated with the previously proposed palaeobotanical models.

10

The middle to Late Eocene evolution of nummulitid foraminifer Heterostegina in the Western Tethys

80%

Less G. , Ozcan E. , Papazzoni C. A. , Stockar R.

Acta Palaeontologica Polonica

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2008

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tom 53

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nr 2

EN

Megalospheric forms of Western Tethyan late Bartonian to late Priabonian involute Heterostegina from numerous localities, marking different ecological conditions, were morphometrically investigated. They belong to three species, H. armenica, H. reticulata, and H. gracilis based on the presence/absence of granulation, on the chamberlet characteristics and on the relative size of proloculus. Within these species a very rapid evolution could be observed in the reduction of the number of operculinid chambers, in the increase of the number of chamberlets and partially in the increase of the proloculus size. This evolution is demonstrated by stratigraphic superpositions in several localities (especially in the Mossano section), and is supported also by the change of co−occurring fossils, starting with the disappearance of large−sized Nummulites, then followed by the appearance of the genus Spiroclypeus and then by the disappearance of orthophragmines of middle Eocene acme. Based on the reduction of operculinid chambers, two chronosubspecies of Heterostegina armenica and seven of H. reticulata are defined biometrically (four of them: H. armenica tigrisensis, H. reticulata tronensis, H. r. hungarica, and H. r. mossanensis are introduced here). This allows to subdivide the Shallow Benthic Zone (SBZ) 18 into three and SBZ 19 into two subzones. The extremely rapid evolution of H. reticulata allows to calibrate larger foraminiferal events around the middle/late Eocene boundary. The extinction of large−sizedNummulitesseems to be heterochronous in the late Bartonian in having migrated eastward, while the first appearance of Spiroclypeus is shown to be synchronous at the base of the Priabonian. The middle/upper Eocene (= Bartonian/Priabonian) boundary is to be placed at the base of the Priabona marls in the Mossano section corresponding to the SBZ 18/19 limit, to the first appearance of genus Spiroclypeus, to that of Nummulites fabianii and of Heterostegina reticulata mossanensis. It falls into the upper part of both the P 15 and NP 18 planktic zones. The Western Tethyan Eocene involute Heterostegina became extinct, apparently with no Oligocene successors.

11

Eocene flora and trace fossils from the Hruby Regiel section in the Tatra Mountains (Poland): Taxonomic revision of the Wiktor Kuźniar fossil plant collection

70%

Worobiec G. , Jach R. , Machaniec E. , Uchman A. , Worobiec E.

Acta Geologica Polonica

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2015

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tom Vol. 65, no. 2

203--226

EN

Latest Eocene plant macrofossils and trace fossils collected a century ago by Wiktor Kuźniar are revised and their stratigraphical and palaeoecological meaning is re-considered. They derive from marine limestones and marls cropping out on the northern slope of the Hruby Regiel mountain in the Western Tatra Mountains. Leaves belonging to the families Fagaceae and Lauraceae and fruits of the palm Nypa are recognized. The co-occurrence of the planktonic foraminifer taxa Chiloguembelina cf. gracillima and Globigerinatheca cf. index and fruits of Nypa suggests a latest Eocene age of the fossil flora. The plant assemblage is typical of paratropical or subtropical evergreen forests in a warm and humid subtropical climate, recent counterparts of which occur in southeast Asia. The presence of Nypa is characteristic of mangroves. The good state of preservation of the leaves suggests coastline proximity during sedimentation of the plant-bearing deposits.