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1.
The northern Canadian Cordillera can be divided into three more or less parallel arrayed lithofacies, which from east to west correspond to progrcssively deepening waters. The shallow water, yellow, or orange-weathering carbonates occupy essentially the eastern half of the region and northwestern Yukon. Shallowest water carbonates yield fairly abundant ostracodem faunas, ostracodes, and little else. Slightly deeper water carbonates contain brachiopod faunas rich in individuals but low in generic diversity. The name Howellella-Protathyris Community is applied to the Lower Lochkovian shallow water faunas: the Sieberella-Nymphorhynchia-Athyrhynchus Community is the approximate Upper Pragian-Zlichovian equivalent. Deep water calcareous shales and limestones occupy a narrow band and yield faunas rich both in number and diversity. These faunas are designated the Skenidioides-Spirigerina-Vagrania Community and are recognized through the entire Lower Devonian interval. An intermediate depth fauna from Upper Pragian and Zlichovian dark carbonates is probably recognizable in northwestern Yukon, and termed the Strophochonetes-Proreticularia- receptaculitid Community. The widespread deep water graptolitic shales and carbonates contain a rich fauna of graptolites and relatively rare trilobite, sponge, and brachiopod faunas. 相似文献
2.
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
3.
K. S. HABGOOD 《Botanical journal of the Linnean Society. Linnean Society of London》2000,133(2):203-227
Two examples of fragmentary, coalified plant fossils with cellular preservation and in situ spores are described using scanning and transmission electron microscopy (SEM and TEM), from a Lower Devonian (Lochkovian) locality in the Welsh Borderland. A sporophyte which produced dyads of ?Cymbohilates of. horridus is unique in that stomata are numerous on the supporting axis, and are comparable with those described from contemporary vascular plant remains. The in situ dyads possess a bilayered exospore wall, with an outer exosporal envelope present over the distal faces. A fusiform sporangium, with externally smooth epidermis, contains specimens of the tetrad Velatitetras sp. Each tetrad is encompassed by a laevigate, folded, exosporal envelope of uniform thickness, which contains a layer of regular voids. Spores within the tetrads are ultrastructurally bilayered, with a complex, digitate outer margin presumably representing spore wall ornamentation. Neither the tetrads nor dyads reported in this paper are lamellate in ultrastructure. The combination of stomata, branching and dyads in the same sporophyte holds significance for the understanding of cryptospore affinities. 相似文献
4.
DIANNE EDWARDS F.L.S P. KENRICK 《Botanical journal of the Linnean Society. Linnean Society of London》1986,92(3):269-283
A new monotypic genus is described from impression and compression fossils preserved in the Senni Beds of the Lower Old Red Sandstone of S Wales. The new species has scattered reniform lateral sporangia suggesting zosterophyll affinity, but supporting anatomical evidence is lacking. The axes of the plant are characterized by occasional large surface protuberances, sometimes extended into lateral projections of variable length and morphology. Taphonomic factors account for some of the observed features of the fossils, and their unusual orientation in the sediment suggests that Tarella may have grown on exposed point bars. 相似文献
5.
Two new species and two new genera (Pachyphasma, Striatophasma) of Mantophasmatodea are described from Namibia. Pachyphasma brandbergense is endemic to the Brandberg massif; Striatophasma occupies an extensive area south of the region inhabited by Mantophasma. Phylogenetic analyses (see Predel et al. in press) suggest a sistergroup relationship of Striatophasma and the South African Austrophasmatidae. 相似文献
6.
Rachel A. Moore Derek E. G. Briggs Christoph Bartels 《Pal?ontologische Zeitschrift》2005,79(3):399-408
A new specimen of the synziphosurine arthropodWeinbergina opitzi is described from the Lower Devonian (Lower Emsian) Hunsrück Slate of Germany (Rhenish Slate Mountains). It is the smallest and only the fifth specimen of this taxon to be described and is preserved in ventral aspect with exceptional preservation of prosomal and opisthosomal appendages. This specimen confirms the presence of a seventh appendage, similar in morphology to the preceding prosomal appendages, associated with opisthosomal segment one. In addition, at least three opisthosomal plates fringed with teeth are confirmed. Correlation of prosomal appendage podomeres betweenWeinbergina and selected chelicerate taxa shows that appendage structure is most similar to eurypterid appendages III–IV and Araneae appendages III–VI. This is in contrast to modern horseshoe crabs which have fewer podomeres in appendages II–V due to an undifferentiated tibiotarsus. 相似文献
7.
DONALD L. J. QUICKE 《Zoologica scripta》1989,18(1):139-143
Fuvihracon gen.n. (typc-species: Fuvibracon gauldi sp.n.) and Spurhulibrucon (type-species: Sparhulibracon dayi sp.n.), both lrom Brunei, are described and illustrated. The relationships of the two new genera and of the Carnpyloneurus Szépligeti and Chelonogaslra Ashmead generie groups are discussed. 相似文献
8.
TOR. ØRVIG 《Zoological Journal of the Linnean Society》1967,47(311):131-153
The following material is described: (a) a climatiid shoulder girdle from the Old Red of Podolia and the British Lower Old Red Sandstone, and (b) ischnacanthid jaw-elements and a fin spine from the Lower Devonian of Vestspitsbergen. A discussion is given of the shoulder girdle in Climatius reticulatus and of the characters distinguishing the dentigerous jaw-bones of the Ischnacanthidae from those of the early Climatiidae. It is pointed out that in the dermal skeleton of the Climatiidae one may trace phylotie changes in the structure of mesodentine and bone tissue closely paralleling those of the corresponding hard tissues in the Osteostraei. A trend towards the emergence of acellular bone tissue is traceable not only in the Climatiidae but also in certain parts of the dermal skeleton of the Ischnacanthidae. 相似文献
9.
The calceocrinid crinoids Eohalysiocrinus latus and E. convexus, formerly considered as endemic in theBarrandian and restricted to organodetrital limestones, have been discovered in a shaly layer at the top of the Beg an Arreun Formation (upper Emsian, upper Zlichovian) in the western part of the Armorican massif. A new species, Ramacrinus brevis, found simultaneously in Bohemia and Brittany, is described. It is suggested that the incursions of hercynian faunal elements into the rhenish associations of the Brest area may be in relation with paleogeographical changes allowing communication between the Barrandian and the western part of Europe and migration of both pelagic and benthic organisms. 相似文献
10.
Sterile and fertile shoots of a microphyllous vascular plant are described from the Lower Devonian Posongchong Formation (? upper Siegenian), Yunnan Province, southern China and placed in the new taxon Halleophyton zhichangense gen. et sp. nov. The sterile axes are characterized by conspicuous, contiguous swollen rhomboidal to hexagonal leaf bases and relatively broad spatulate laminae. The relief of the leaf bases is not so pronounced in the fertile areas, which bear numerous cauline sporangia with two equal valves. In vegetative characters the new fossils, although smaller and more fragmentary, resemble Drepanophycus gaspianus but in the absence of information on the fertile parts of the latter and because of the controversy surrounding the concept of the genus Drepanophycus, we decided to erect a new genus. Its relationship to the lycophytes sensu stricto is equivocal as exact details of the relationship of sporangium with leaf and sporangium vascularization remain unknown. 相似文献
11.
12.
Yoshihiko Machida 《Ichthyological Research》1993,39(4):281-286
Two new bythitid genera and species of the subfamily Brosmophycinae are described from Northern Territory, Australia.Brosmolus longicaudus, described from a single male specimen, is unique in the tribe Brosmophycini in having the anal fin origin well anterior to the midpoint of the body and thin, transparent skin on the head and body.Beaglichthys macrophthalmus, described from a single female specimen, differs from all other genera in the subfamily by the following combination of characters: eight branchiostegal rays, eye diameter longer than snout length, cheek scaly, anal fin origin at midpoint of body, three developed rakers on the first gill arch, 12 caudal fin rays, and 14 precaudal vertebrae. 相似文献
13.
本文报道中国■目昆虫■科Phasmatidae与异■科Heteronemiidae各1新纪录属:叶尾■属ACro-phylla Gray和副厚■属Parapachymorpha Brunner;及其各1新种:四川叶尾■Acrophylla sichuanensis,sp.nov.和四刺副厚■Parapachymorpha tetracantha,sp.nov.模式标本保存于西北农业大学昆虫标本馆。 相似文献
14.
V. V. Baranov 《Paleontological Journal》2018,52(3):255-264
New atrypids are described from the Lower Devonian of Northeast Russia: Musalitinispira, gen. nov. with type species M. dogdensis, sp. nov. (subfamily Atrypinae), Spinatrypina (Spinatrypina) krivensis, sp. nov., and Datnella, gen. nov. with type species D. datnensis (Baranov, 1995) (subfamily Spinatrypinae). 相似文献
15.
The most species-rich and widespread crinoid clade in the type area of the Devonian of south-west England is the monobathrid camerate family Hexacrinitidae Wachsmuth and Springer. These crinoids occur either as thecae (Middle Devonian) or pluricolumnals and columnals (Lower to Upper Devonian). The first new, nominal species of hexacrinitid, probably Oehlerticrinus Le Menn, to be described from this region since the nineteenth century is Oehlerticrinus peachi sp. nov. from the Lower Devonian Looe Basin of southern Cornwall. This specimen is mouldic and somewhat flattened, retaining the proxistele and arms. Diagnostic features include the heteromorphic proxistele with circlets of long, unbranched radices directed towards the crown; the high, box-like (=skyphosiform) theca with a flattened base; a thecal plate sculpture of tubercles and ridges arranged in triangles; and the pinnulate arms. Any uncertainty in identifying this species at the generic level rests with the arms being pinnulate, not ramulose as is common in Hexacrinites Austin and Austin, indicating that O. peachi is closer to Oehlerticrinus Le Menn. 相似文献
16.
J. QUINLAN 《Systematic Entomology》1976,1(1):65-69
Psichacra marshalli Cameron is redescribed and assigned to the new genus Pseudopsichacra. ‘New Genus B’ of Weld is redescribed as Bewelda gen.n. and striata sp.n. is designated as the type–species. An emendation of Weld's key is included to show the positions of both genera. 相似文献
17.
Tauroprimnoa austasensis gen. nov., sp. nov. and Digitogorgia kuekenthali gen. nov., sp. nov. are described and illustrated from Southern Ocean waters. The most distinctive characters of the newly
proposed genera are, in Tauroprimnoa, the existence of four marginal scales, two abaxials with a strong thorn, and the presence of a single abaxial longitudinal
row of body scales. In the case of Digitogorgia, the colony branching pattern, the structure of the opercular scales, and the presence of a complete cycle of accessory opercular
scales are the distinct features to distinguish it from previously known genera. Tauroprimnoa austasensis sp. nov. is reported from the Eastern Weddell Sea, Antarctica, while Digitogorgia kuekenthali sp. nov. has been found in the SubAntarctic waters off Burdwood Bank and, in the south east of Isla Nueva in Chilean Patagonia. 相似文献
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19.
A new genus Lyalia is described in Nanophyidae and three species are included in it: Lyalia curvatasp. n. (Vietnam), Lyalia robusta (Pic, 1921), comb. n. (from Nanophyes) (Java, Bali, Laos) and Lyalia albolineata (Pajni & Bhateja, 1982), comb. n. (from Ctenomerus) (India: Assam). Ctenomerus lagerstroemiae G. A. K. Marshall, 1923 is a syn. n. of Lyalia robusta. Thus, the genus Ctenomerus Schoenherr, 1843 is restricted to the Afrotropical Realm. Kantohiagen. n. is erected for Kantohia taiwana (Kantoh & Kojima, 2009) (from Shiva) (Taiwan). A key to the Nanophyinae genera with six desmomeres is presented. 相似文献