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EN
A single middle trunk vertebra from the Sakurado Facies of the Yamanouchi Member of the Akeyo Formation (late Early Miocene), Mizunami City, central Japan, is identified as cf.Trimeresurus (a living crotaline genus) based on the very close morphological similarity of the fossil to the modern and Pleistocene species Trimeresurus flavoviridis (HALLOWELL, 1861) and on zoogeographic grounds. This is the oldest record of the Crotalinae from Asia. Additional fossil material of this crotaline is needed in order to make a more specific identification.
4
Content available Ewolucyjna utrata kończyn u jaszczurek
84%
Kosmos
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2017
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tom 66
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nr 3
435-440
PL
Redukcja kończyn u łuskonośnych, zaszła w obrębie 52 linii ewolucyjnych przynajmniej 62 razy, z czego w przypadku jaszczurek, redukcje w obrębie obu kończyn jednocześnie zaszły 20 razy. Wśród jaszczurek o zredukowanej liczbie kończyn (lub też paliczków), występują dwa główne typy morfologiczno-ekologiczne, które można określić mianami "krótkoogonowych kopaczy" i "długoogonowych lądowców". Jedną z teorii tłumaczących zanikanie, lub też redukcje składowych części kończyny, jest usprawnienie metod ucieczki przed drapieżnikiem - teoria ta jest dobrze opisana na przykładzie scynków z rodzaju Chalcides. Alternatywna hipoteza wyjaśnia redukcje kończyn adaptacją do drapieżnictwa. Przykładami jaszczurek, które obrały tą strategię są australijskie Pygopodidae, których przedstawiciele spełniają ekologiczną funkcję węży.
EN
Reduction of limbs has occurred within 52 evolutionary lines of Squamata at least 62 times, of which in the case of lizards, the manus and pes has been reduced together at least 20 times. Among lizards with the reduced number of limbs (or phalanges), there are two morpho-ecological types, which can be named "short tail diggers" and "long tail surface dwellers". One of the theories explaining the occurrence of loss of the whole limbs or reduction of their parts points to improvement of the ways of escape from the predators. This theory is well supported by an example of genus Chalcides belonging to the skinks family. The cause of limb reduction in the Australian Pygopodidae is different, as they play an ecological function of snakes and their limb reduction is an adaptation to hunt.
EN
South American Mesozoic snake diversity is mostly represented by genera from the Cenomanian (Najash), Santonian– Campanian (Dinilysia), and Campanian–Maastrichtian (Alamitophis, Patagoniophis, Rionegrophis, and Australophis) of Patagonia, Argentina. In this paper, we describe a new snake genus and species, Seismophis septentrionalis, from the Cenomanian (early Late Cretaceous) of the Alcântara Formation, Maranhão, northeastern Brazil. The new snake comprises a posteriormost trunk vertebra and possibly a poorly preserved midtrunk vertebra. Both vertebrae share small size, zygosphene moderately thick with a rectilinear roof, absence of paracotylar foramina, presence of parazygantral foramina, and strongly marked parasagittal ridges of the neural arch. The new snake is here considered of uncertain systematic affinities, but probably close to the limbed snake Najash rionegrina. Although the material is very fragmentary and the systematic assignment is still unresolved, this snake represents the oldest, as well as probably the most primitive snake from Brazil.
EN
We presented the first data on female reproductive traits of the meadow lizard Darevskia praticola from the westernmost boundary of the species range (Peridanubian Serbia). Mating occurs during April and May, oviposition period occurs in June, and hatching takes place in July. Females mature at body sizes of 49.5 mm of snout-vent length (SVL). One clutch is produced annually. The average clutch size of 5.7 eggs (range 4 – 8) represents the largest recorded for this species. Clutch size and clutch mass increased significantly with the mother’s SVL. There was no evidence of the predicted trade-off between egg size and clutch size, as well as of variation in egg size associated with maternal SVL. The relative clutch mass (RCM) was rather high (0.60) for lacertid species and was not correlated with female size.
|
|
tom 54
|
nr 1
41-44
EN
Falcaustra desilvai sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Cnemaspis aff. tropidogaster (Squamata, Gekkonidae) is described and illustrated. Falcaustra desilvai represents the 4th nematode species from Sri Lanka to be assigned to the genus and is distinguished from other Sri Lankan species by the distribution pattern of caudal papillae (12 precloacal, 2 adcloacal, 10 postcloacal, and 1 median), length of spicules (956–1046 μm) and absence of a pseudosucker.
EN
Polyglyphanodon sternbergi Gilmore, 1940 is a large−bodied lizard from the Late Cretaceous of North America distinguished by its transversely oriented, interlocking teeth. Initially the teeth of P. sternbergi were described as smooth and blade−like, but recent discoveries of new specimens from the type locality and re−examination of the original material indicate that the chisel−like teeth of P. sternbergi have small, irregular serrations along the blades. These serrations are similar in size to those found on the teeth of the modern herbivorous lizard Iguana iguana and were likely used in a similar manner to crop vegetation, but was also capable of a degree of oral food processing due to the transverse orientation and interlocking arrangement of the dentition of P. sternbergi. Additionally, the presence of transversely oriented teeth with V−shaped blades in the anterior portion of the tooth row of P. sternbergi represents an additional shared characteristic in tooth structure between P. sternbergi and Dicothodon moorensis, Bicuspidon numerosus, and Peneteius aquilonoius; all transversely−tooth polyglyphandontine lizards from the Cretaceous of North America. It appears that the unique dentitions of Polyglyphanodon sternbergi (large teeth with transverse, serrated blades) and Peneteius aquilonius (small teeth with mammal−like specializations) present by the end of the Cretaceous were derived from a bicuspid, transversely oriented precursor tooth with a V−shaped blade.
EN
The Lower Cretaceous (Albian age) locality of Pietraroia, near Benevento in southern Italy, has yielded a diverse assemblage of fossil vertebrates, including at least one genus of rhynchocephalian (Derasmosaurus) and two named lizards (Costasaurus and Chometokadmon), as well as the exquisitely preserved small dinosaur, Scipionyx. Here we describe material pertaining to a new species of the fossil lizard genus Eichstaettisaurus (E. gouldi sp. nov.). Eichstaettisaurus was first recorded from the Upper Jurassic (Tithonian age) Solnhofen Limestones of Germany, and more recently from the basal Cretaceous (Berriasian) of Montsec, Spain. The new Italian specimen provides a significant extension to the temporal range of Eichstaettisaurus while supporting the hypothesis that the Pietraroia assemblage may represent a relictual island fauna. The postcranial morphology of the new eichstaettisaur suggests it was predominantly ground−living. Further skull material of E. gouldi sp. nov. was identified within the abdominal cavity of a second new lepidosaurian skeleton from the same locality. This second partial skeleton is almost certainly rhynchocephalian, based primarily on foot and pelvic structure, but it is not Derasmosaurus and cannot be accommodated within any known genus due to the unusual morphology of the tail vertebrae.
EN
Falcaustra papuensis sp. nov. (Ascaridida, Kathlaniidae) from the large intestine of Sphenomorphus simus (Squamata, Sciencidae) is described and illustrated. Falcaustra papuensis represents the 4th Australo-Papuan species assigned to this genus and is distinguished from other Australo-Papuan species by the distribution pattern of caudal papillae (6 precloacal, 6 adcloacal, 8 postcloacal, and 1 median), length of spicules (561–714 μm) and presence of a pseudosucker. Sphenomorphus simus was found to harbor 2 additional species of nematodes, Meteterakis crombiei and Oswaldocruzia bakeri. Sphenomorphus simus represents a new host record for each of these nematode species.
EN
Mathevotaenia panamaensis sp. nov. (Cestoda, Anoplocephalidae, Linstowiinae) from a green spiny lizard, Sceloporus malachiticus, collected in Panama is described. This is the first species of Mathevotaenia reported from a lizard host. The new species is most similar to Mathevotaenia bivittata in that mature eggs are concentrated along the lateral margins of the proglottids. Major differences between the two species include oval cirrus sac in M. bivittata, a spherical cirrus sac in M. panamaensis; ovary compact consisting of 10–15 short lobules in M. bivittata, ovary bilobed with each lobe consisting of 3–4 lobules in M. panamaensis.
EN
Rhabdias mcguirei sp. nov., is described on the basis of specimens found in the lungs of northern Philippine flying lizards, Draco spilopterus (Reptilia, Agamidae) collected in Aurora province, Luzon Island, Philippines. It is characterized by a rounded oral opening, a buccal capsule consisting of anterior and posterior parts, and the shape of the cuticular inflation in the anterior part of the body: the cuticle is less inflated in the anterior-most part, with the inflation gradually thickening up to the level of the oesophageal-intestinal junction. The new species is differentiated from the 11 most closely related species of Rhabdias previously known from lizards.
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