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E. M. Baykina 《Paleontological Journal》2012,46(3):302-312
Two collections of clupeid fishes, which have previously been assigned to the species Sardinella sardinites (Heckel, 1850), from the Lower and Middle Sarmatian of the Pshekha River Basin (Western Ciscaucasia, Krasnodar Region) were studied. A new genus, Illusionella gen. nov., with two species, I. tsurevica sp. nov. and I. pshekhensis sp. nov., was described based on morphological characteristics. They are the most abundant species in Sarmatian fish assemblages of the Psekups-Belaya interfluve. 相似文献
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Gravid ovaries were examined histologically from two species of Nomorhamphus and 21 populations of Dermogenys. In addition, changes in dry-weight throughout gestation are provided for 15 populations. The ovaries are paired organs running along the lateral body wall and are separated along most of their length. In all specimens examined, embryos are fertilized within the ovarian follicle. Viviparity in these species is divided herein into five categories designated types I–V. In types I and II the entire gestation period is intrafollicular, whereas in types III–V only the early stages of gestation are intrafollicular with the major period of development occurring in the ovarian lumen (intraluminal). Type I is characterized by the retention of a large amount of yolk throughout gestation. Superfetation is not observed. Populations of D. pusilla from Vietnam and Thailand decrease in dry-weight throughout gestation. This, coupled with the slight vascularization of the yolk sac, suggests strict lecithotrophy. Populations of D. pusilla from Singapore and Bangladesh undergo an increase in dry weight and exhibit an increased vascularization of the yolk sac, suggesting a form of unspecialized matrotrophy. Type II is characterized by a small amount of yolk, an expansion of the coelomic cavity and pericardial sac, and a simple cuboidal epithelium on the general body surfaces. Superfetation occurs with up to three broods present within a single ovary. Dermogenys pusilla from Sabah, D. orientalis and Dermogenys sp. (Sulawesi) exhibit the type II form of viviparity. Dermogenys vivipara from the eastern Philippine islands of Culion and Busuanga exhibit characteristics considered intermediate between type I and II. These results are compared with those from other viviparous species exhibiting intrafollicular gestation. In species with types III–V (intraluminal gestation), developing oocytes are restricted to a distinct ridge of ovigerous tissue extending along the entire length of the ovary. Two species, D. viviparus (Luzon, Philippines) and Dermogenys sp. (Luzon) have the type III form of viviparity. In this form, oocytes are small (0.8–1.0 mm) with little yolk reserves and embryos, covered with a simple cuboidal epithelium and possessing an expanded belly sac, are retained within the follicles until a late fin-bud stage. Type III embryos found within the ovarian lumen have a greatly expanded belly sac and remain covered by a simple cuboidal epithelium until parturition. Superfetation is present in these species with two broods observed simultaneously within a single ovary. Five species, D. megarrhamphus, D. weberi, D. viviparus (Jolo, Philippines), Nomorhamphus sp. (Sulawesi), and N. towoetii, were observed with the type IV form of viviparity. Embryos in this category are evacuated into the ovarian lumen prior to a fin-bud stage and retain a large yolk mass throughout development. Superfetation is absent in these species. A differentform of viviparity (type V) is present in D. ebrardtii in which embryos appear to obtain nutrients through a form of oophagy and aldelphophagy (feeding on developing oocytes or less-developed siblings). In all specimens with intraluminal development, atretic oocytes within the ovigerous ridge are abundant. These findings support the hypothesis that current species and generic limits may be artificial and underscores the potential of histological evidence for phylogenetic analysis of this group. J. Morphol. 234:295–317, 1997. © 1997 Wiley-Liss, Inc. 相似文献
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Systematic Parasitology - A new nematode species, Philometra longa n. sp. (Philometridae), is described from male and female specimens collected from the body cavity of the marine fish,... 相似文献
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Detlev Thies 《Pal?ontologische Zeitschrift》1992,66(1-2):137-146
The diagnosis of the fossil neoselachian genusPalaeospinax Egerton 1872 is revised. A new species from the Lower ToarcianPosidonia Shale of Southern Germany is described asPalaeospinax politus n. sp. It differs from all other known members of the genus in having smooth anterior and lateral teeth. 相似文献
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Gomez B Martín-Closas C Barale G Thévenard F 《Review of Palaeobotany and Palynology》2000,111(1-2):49-70
A new species of the formerly monospecific genus Nehvizdya Hlustík, Nehvizdya penalveri sp. nov. is described from the Albian of the Escucha Formation (Eastern Iberian Ranges, Teruel, Spain). The type species Nehvizdya obtusa Hlustík was first found in the Lower-Middle Cenomanian Peruc Member of the Peruc-Korycany Formation (Bohemian Massif, Czech Republic). Both taxa closely resemble each other, not only in leaf shape and venation pattern, but also in their epidermal structures and the occurrence of resin bodies. The Spanish species, however, is notable for its marked amphistomatic leaves with stomatal apparatus, which have inner folds inside the stomatal pits. Comparison with Eretmophyllum andegavense Pons et al. from the Cenomanian of the Baugeois Clays (Maine-et-Loire, France) allows us to transfer this species to the genus Nehvizdya Hlustík. The new combination proposed is Nehvizdya andegavense (Pons et al.) comb. nov. A taphonomic analysis in this layer appears to characterise a biocoenosis formed from N. penalveri sp. nov. and Frenelopsis alata (K. Feistmantel) Knoblock. Similar associations have been described in the Czech and French Cenomanian. In all three cases, the associations grew around coastal lagoons and ponds where they formed a shrubby halophyte vegetation. 相似文献
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Noel H. Holmgren 《Brittonia》1978,30(4):416-425
Penstemon goodrichii of sect.Cristati andP. navajoa andP. moriahensis of sect.Glabri are described, illustrated and mapped. Their relationships to kindred species are discussed. 相似文献
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A new species of Adelophthalmus (Eurypterida) from the lower carboniferous of the Krasnoyarsk Region
E. S. Shpinev 《Paleontological Journal》2006,40(4):431-433
A new species of Adelophthalmus, a genus recorded infrequently in the former Soviet Union, is described from the Tournaisian of the Krasnoyarsk Region. 相似文献
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A new species of the genus Telangiopsis, T. nonnae O. Orlova et Zavialova, was described on the basis of a microsporangiate organ from the Lower Carboniferous deposits of the
Novgorod Region. The morphology of branching fertile axes, synangia, and sporangia was thoroughly studied. The three-dimensional
system of fertile axes branches monopodially; ultimate axes bear numerous connivent bunches of synangia, which consist of
three to six basally fused elongated ovate sporangia. The morphology and ultrastructure of prepollen grains were studied,
which were extracted from the rock matrix surrounding the sporangia. The two-layered exine includes a well-developed endexine
and an alveolate ectexine, with one-three rows of large thin-walled alveolae. The new species was compared with other Early
Carboniferous microsporangiate organs. 相似文献
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S. V. Moloshnikov 《Paleontological Journal》2009,43(3):306-310
A new pycnosteid species, Schizosteus shkurlatensis sp. nov. (Agnatha, Psammosteiformes), from the Staryi Oskol beds (Givetian, Middle Devonian) of the Voronezh Region is described. This is the first species of the genus Schizosteus Obruchev from the Central Devonian Field. The similarity between species of this genus and early species of Psammolepis is discussed. 相似文献
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A new species of Ameripodius (Aves: Galliformes: Quercymegapodiidae) from the Lower Miocene of France 总被引:1,自引:0,他引:1
Cécile Mourer-Chauviré 《Palaeontology》2000,43(3):481-493
The Quercymegapodiidae, primitive galliforms resembling recent megapodes, have been described from the Upper Eocene of Quercy, France. They have also been identified in the Upper Oligocene–Lower Miocene of Brazil, where they are represented by the genus Ameripodius Alvarenga. A new species of this genus, Ameripodius alexis sp. nov., from the Lower Miocene of France, is described here. The occurrence of the same genus on both sides of the Atlantic Ocean emphasizes the similarities between South American and European avifaunas during the early Tertiary. New discoveries indicate that a similar avifauna was also present in North America, and that a characteristic association of taxa can be defined for the group that includes South America, North America and Eurasia. However, so far as is known, the same avifauna does not occur in contemporaneous African avifaunas. 相似文献
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A new species of lace-bug Sinaldocader ponomarenkoi sp. nov. (Tingidae: Phatnomatini) is described from the Lower Cretaceous Transbaikalian locality Baissa. The new species differs from the type species S. drakei Popov, 1989 from the Lower Cretaceous of Mongolia in the well-developed lateral carinae of pronotal disc and in the details of hemelytral venation. 相似文献
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Two new species of the genus Stenandra Lameere, 1912 are described: Stenandra saitoae from Sulawesi of Indonesia and Stenandra asiatica from Vietnam. A key to the species of the Stenandra is given. 相似文献
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Felippe-Bauer ML Damasceno CP Trindade RL Py-Daniel V 《Memórias do Instituto Oswaldo Cruz》2010,105(7):863-865
A new species of the Culicoides reticulatus species group, Culicoides kuripako Felippe-Bauer, is described and illustrated based on females and male specimens from the states of Amazonas and Pará, Brazil. The new species is compared with its similar sympatric congener, Culicoides paucienfuscatus Barbosa. 相似文献
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M. V. Nabozhenko Chang Huali Xu Li Pu Hanyong Jia Songhai 《Paleontological Journal》2015,49(13):1420-1423
A new genus and species of comb-clawed beetles, Calcarocistela kirejtshuki gen. et sp. nov., from the Lower Cretaceous of Yixian (China) is described. The new genus is assigned to the tribe Gonoderini of the subfamily Alleculinae (family Tenebrionidae) based on the following characters: five visible abdominal ventrites, nonwidened tarsomeres without a membranous ventral lobes, and serrate antennae. The new genus differs from other members of the tribe Gonoderini in the long spurs of metatibia reaching a half of the first metatarsomere and the lamellate prosternal process. Calcarocistela kirejtshuki is the first member of Alleculinae from the Lower Cretaceous. 相似文献
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Jaime Güemes 《Folia Geobotanica》1999,34(3):363-372
A new species ofFumana (Dunal) Spach subgenusFumana, F. fontqueri, is described from the region of Rif, Morocco. Notes on its morphology, ecology, distribution and taxonomic relationships are presented. It differs fromF. procumbens (Dunal) Gren. etGodr. andF. baetica Güemes, by the indument of the stem, the disposition of pedicels, and the size of the flowers. 相似文献
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Anew osteostracan genus and species,Victoraspis longicornualis n. gen., n. sp., is described based on material from Rakovets’, present day Ukraine. This new taxon shares characters with the two generaStensiopelta Denison, 1951 andZychaspis Janvier, 1985. A phylogenetic analysis supports the position ofVictoraspis as the sister group to a monophyleticStensiopelta, while the interrelationships of the various species ofZychaspis are poorly resolved. A morphometric analysis is carried out in an attempt to further resolve the taxonomic affinity. This analysis groups all examinedZychaspis species closely together, and further supports the establishment ofVictoraspis as separate genus. 相似文献
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Two new and the only known extinct seahorse species Hippocampus sarmaticus and Hippocampus slovenicus are described from the Middle Miocene beds (Lower Sarmatian) in Slovenia, representing the oldest known fossil record of seahorses. Hippocampus sarmaticus was most similar to the extant seahorse species Hippocampus trimaculatus, while H. slovenicus can be most easily compared to the extant pygmy seahorses H. bargibanti, H. denise, and H. colemani. These Sarmatian seahorses lived among seagrasses and macroalgae in the temperate shallow costal waters of the western part of the Central Paratethys Sea. 相似文献