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1.
The placoderm Plourdosteus livonicus (Eastman) (Euarthrodira, Coccosteina) from the Upper Timanian Mikhailovskii Fish Assemblage of the Central Devonian Field is described. The composition and structure of the assemblage are discussed and compared with later Frasnian fish assemblages of the Central Devonian Field.  相似文献   

2.
Psammosteiforms, including Tartuosteus (?) zheleznogorskensis, sp. nov. and Psammosteus cf. P. praecursor Obruchev, from the Lower Frasnian (Upper Devonian) of the Mikhailovskii Mine (Kursk Region) are described. Agnathans, placoderms, crossopterygians, and acanthodians from this locality are determined. The similarity of the Mikhailovskii Fish Assemblage to the assemblage of southern Timan suggests it be assigned to the Upper Timan Regional Stage.  相似文献   

3.
A new genus and species of pachyosteomorph arthrodire, Omalosteus krutoensis gen. et sp. nov. from shallow-water marine deposits of the Evlanovo Regional Stage (Upper Frasnian, Upper Devonian) of the Central Devonian Field is described. It is tentatively referred to the family Trematosteidae Gross, 1932, which was earlier believed to be endemic to central Europe. The new genus is characterized by a rounded, dorsoventrally compressed cross section of the pectoral region and smooth head shield and postcranial membrane bones. The centrale is elongated, forming a narrow lateral lobe. The praeorbitale, postorbitale, and centrale come in contact in the center of the orbital region. The mediodorsale is wide, its carinal process projects considerably posteriorly. The anterior margin of the anterior ventrolaterale lacks articular facets for the interlaterale.  相似文献   

4.
A new spiriferid genus Paraimbrexia with the type species Imbrexia topkensis Besnossova, 1959 is established within the family Imbrexiidae Carter, 1992 from the Abyshevo Horizon, Famennian, Upper Devonian of the Kuznetsk Basin. Revision of the type material of I. topkensis revealed that this species strongly differs from the other species of Imbrexia Nalivkin, 1937 in details of shell exterior and interior.  相似文献   

5.
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   

6.
Summary  A new monotypic bamboo genus Phuphanochloa (Poaceae: Bambusoideae) from north-eastern Thailand is described, together with a new species, P. speciosa.  相似文献   

7.
Alansmia, a new genus of grammitid ferns is described and combinations are made for the 26 species known to belong to it. Alansmia is supported by five morphological synapomorphies: setae present on the rhizomes, cells of the rhizome scales turgid, both surfaces of the rhizome scales ciliate, laminae membranaceous, and sporangial capsules setose. Other diagnostic characters include pendent fronds with indeterminate growth, concolorous, orange to castaneous rhizome scales with ciliate or sometimes glandular margins, hydathodes often cretaceous, and setae simple, paired or stellate. The group also exhibits the uncommon characteristic of producing both trilete and apparently monolete spores, sometimes on the same plant. New combinations are made for Alansmia alfaroi, A. bradeana, A. canescens, A. concinna, A. contacta, A. cultrata, A. dependens, A. diaphana, A. elastica, A. glandulifera, A. heteromorpha, A. immixta, A. kirkii, A. lanigera, A. laxa, A. longa, A. monosora, A. reclinata, A. semilunaris, A. senilis, A. smithii, A. spathulata, A. stella var. stella, A. stella var. flava, A. turrialbae, A. variabilis, A. xanthotrichia. Lectotypifications are made for Alansmia concina, A. variabilis, Polypodium ciliare, P. flexile, and P. ovalescens. The genus is named in honor of pteridologist Alan R. Smith.  相似文献   

8.
9.
Summary   Funastrum rupicola Goyder, a new species of Apocynaceae: Asclepiadoideae from Bolivia, is described and illustrated. The conservation status of this species is assessed.  相似文献   

10.
Summary  A taxonomic revision of the palm genus Podococcus (Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined to Gabon. The taxonomic history, morphology, distribution and conservation status of the genus and each species are discussed  相似文献   

11.
A new linoproductid genus is described from the provincial Terrakea arguta Zone (lower part of the Upper Kazanian Substage) of the key section of the Tsagan-Temete Horizon (Kazanian Stage-Lower Tatarian Substage) of northeastern Mongolia. The type species of the new genus was found in the middle layers of the Lower Uldza Subformation, which contains numerous diverse productids from the genus Terrakea.  相似文献   

12.
13.
Native Terminalia spp. in West Africa provide a popular source of construction timber as well as medical, spiritual and social benefits to rural populations. Very little is, however, known regarding the diseases that affect these trees. During an investigation into possible diseases of Terminalia spp. in Cameroon, orange to yellow fungal fruiting structures, resembling those of fungi in the Cryphonectriaceae, were commonly observed on the bark of native Terminalia ivorensis, and on dead branches of non-native Terminalia mantaly. In this study the fungus was identified based on morphological features as well as DNA sequence data (ITS and β-tubulin) and its pathogenicity was tested on T. mantaly seedlings. Our results showed that isolates of this fungus represent a previously undescribed genus in the Cryphonectriaceae, which we describe as Aurifilum marmelostoma gen. et sp. nov. Pathogenicity tests revealed that A. marmelostoma is pathogenic on T. mantaly. These tests, and the association of A. marmelostoma with disease symptoms on T. ivorensis, suggest that the fungus is a pathogen of this important tree.  相似文献   

14.
New conodont species of the genus Polygnathus (P. krutoensis sp. nov., P. makhlinae sp. nov., P. menneri sp. nov., P. obruchevae sp. nov.) are described from the Evlanovian-Livnian (Upper Devonian) deposits of the Voronezh Anteclise (central regions of the Rassian platform). The ontogenetic series of the new species are presented.  相似文献   

15.
Lower Devonian strata from the drill cores from Poland have yielded new Heterostraci material. One ventral shield of Toombsaspis (Traquairaspididae, Phialaspidinae) discovered in the Białopole IG-1 drill core, and a fragment of dorsal shield of cf. Paraliliaspis (Cyathaspididae, Anglaspidinae) with the impressions of internal structures from Ciepielów IG-1 are described and provide new information on paleogeographic disparity of these groups.  相似文献   

16.
Gobius brevis (Agassiz, 1839) was hitherto exclusively based on articulated skeletons. It first appears in the late Early Miocene (late Burdigalian, Karpatian) and is widespread throughout the Middle Miocene. Its previously known zoogeographical distribution was the western Paratethys and the Styrian Basin in Austria. We here report on articulated skeletons ofG. brevis with otoliths in situ from a temporary outcrop at Edenkoben, located in the middle Upper Rhine Graben, Germany. The strata are assigned to the basal part of the Upper Hydrobia Beds. The otoliths in situ are identical with those ofGobius latiformis Reichenbacher, 1992, which is an otolith-based species occurring in the Karpatian and Middle Miocene of the western Paratethys; henceG. latiformis has to be regarded as a younger synonym ofG. brevis (Agassiz, 1839). The skeletons ofG. brevis from Edenkoben differ from other articulated freshwater or brackish water MioceneGobius species in the number of vertebrae, more elongate body shape, and number of fin rays. Also the otoliths ofG. brevis differ in their overall shape from these species. However, the in situ preserved otoliths ofG. brevis in the Edenkoben locality show a more primitive evolutionary stage than the Middle Miocene otoliths ofG. brevis (formerly described asG. latiformis). Thus, the gobiid fishes from Edenkoben belong to the oldest representatives ofG. brevis and must be late Burdigalian in age.Gobius brevis probably migrated into the middle Upper Rhine Graben from the Paratethys area.   相似文献   

17.
Summary  Eleven species comprising the Madagascan genus Vaughania are subsumed within the large pantropical genus Indigofera. Six new combinations are made; the remaining species were originally described in Indigofera.  相似文献   

18.
Summary   Typhonium stigmatilobatum V. D. Nguyen, a new species from Vietnam, is described and illustrated.  相似文献   

19.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.  相似文献   

20.
A new clitocyboid genus of Agaricales, Cleistocybe, is described to accommodate the isolated evolutionary position of the new species Cleistocybe vernalis inferred by a previously published multigene phylogenetic study. Cleistocybe is distinguished from other clitocyboid lineages by a combination of morphological characters, including lamellae that become gray in age, an interwoven hymenophoral trama with divergent elements when young, strongly interwoven pileipellis with pigmented and encrusted hyphae, white spore deposit, a distinct or ephemeral fibrillose to submembranous partial veil, and smooth, inamyloid basidiospores that are inequilateral in profile view. Cleistocybe encompasses two species, C. vernalis and Clitocybe gomphidioides, based on morphological comparisons with C. vernalis. Clitocybe subvelosa is confirmed as conspecific with C. gomphidioides based on morphological and ITS sequence comparisons of type collections. Cleistocybe is known only from western North America in coniferous forests and appears most closely related to the ectomycorrhizal genus Catathelasma and the saprotrophic genera Callistosporium, Macrocybe, and Pleurocollybia based on nLSU-rDNA phylogenetic analysis. Together these lineages constitute the Catathelasma clade.  相似文献   

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