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1.
Cambrian bivalves from the Middle East are reported here for the first time. They come from early “Middle Cambrian” and latest “Early Cambrian” limestones of the lower Çal Tepe Formation at the type locality (near Seydi?ehir, western Taurides). The majority of the new findings consists of Pojetaia runnegari Jell, 1980, but a few specimens of Fordilla sp. represent the first report of this genus from “Middle Cambrian” strata. Based on a compilation of the hitherto reported, but mostly revised Cambrian bivalves, the today widely accepted taxa are discussed. The genera Pojetaia Jell, 1980 and Fordilla Barrande, 1881 are critically evaluated, and three valid species are included in Pojetaia: P. runnegari Jell, 1980, P. sarhroensis Geyer and Streng, 1998, and—with limitations—P. ostseensis Hinz-Schallreuter, 1995. Fordilla also includes three species: F. troyensis Barrande, 1881, F. sibirica Krasilova, 1977, and F. germanica Elicki, 1994. The Cambrian genera Tuarangia MacKinnon, 1982, Camya Hinz-Schallreuter, 1995, and Arhouriella Geyer and Streng, 1998 most probably belong to the class Bivalvia. Palaeoecologically, the Cambrian bivalves of the Western Perigondwanan shelf seem to occur in a relatively small window of low-energy, subtidal, open-marine, warm-water conditions on a muddy carbonate ramp or platform with reduced sedimentation rate. The frequently interpreted infaunal mode of life of Pojetaia and Fordilla is questioned by observations of similarly organized modern bivalves. The palaeogeographical distribution of Pojetaia and Fordilla is discussed with respect to their early ontogeny and to differences in the recent state of knowledge on shelly fossils from Cambrian carbonate successions of Perigondwana.  相似文献   

2.
Two new species viz., Acaricalus indicus n. sp. from Fern (indet) and Neooxycenus dilleniae n. sp. from Dillenia pentagyna Roxb. (Dilleniaceae) are described from West Bengal. Four species viz., Acaphyllisa araucuriae Flechtmann (2000), Aculops pretoriensis Smith Meyer and Ueckermann (1990), Tetra tyrohylae Smith Meyer (1992) and Tetra visci Smith Meyer (1992) are recorded for the first time from India. Besides, 23 other species are reported for the first time from West Bengal. An eriophyoid species is recorded for the first time from a species of Fern in India.  相似文献   

3.
4.
Cheilanthoid ferns (Cheilanthoideae sensu PPG 1 2016) constitute an important group within the Pteridaceae and are cosmopolitan in distribution. In South America, there are 155 species distributed in 13 genera, among which the largest are Adiantopsis (35), Cheilanthes (27), and Doryopteris (22). Most of the cheilanthoid species are morphologically adapted to grow in arid to semi-arid conditions and show convergent evolution, which has implied difficulties in defining the genera throughout their taxonomic history (Copeland 1947, Tryon & Tryon 1973, Gastony & Rollo 1995, 1998, Kirkpatrick Systematic Botany, 32: 504–518, 2007, Rothfels et al. Taxon, 57: 712–724, 2008). Here, we sequenced two plastid markers (rbcL?+?trnL-F) of 33 South American cheilanthoid species, most of which have not been included in phylogenetic analyses previously. The South American species were analyzed together with South African and Australasian Cheilanthes and representatives of related cheilanthoid genera. The phylogenetic analysis showed that most Cheilanthes species are related to the genus Hemionitis, constituting different groups according to their distribution; moreover, three species—C. hassleri, C. pantanalensis, and C. obducta—appear as the sister clade of Hemionitis. Cheilanthes micropteris, the type species, is strongly supported in a clade with Australasian Cheilanthes plus five South American Cheilanthes species, all of which show a reduction in the number of spores per sporangium; this feature would be a synapomorphy for core Cheilanthes s.s. We found no support uniting other South American Cheilanthes to either the group of South African Cheilanthes or to core Cheilanthes s.s. On the other hand, C. geraniifolia, C. goyazensis, and C. bradei formed a clade related to Doryopteris that, with further study, could be considered as a new genus. The phylogenetic hypotheses presented here contribute substantially to the delimitation of Cheilanthes s.s. and related groups and provide the basis for re-examining the generic taxonomy.  相似文献   

5.
6.
The genus Praepedaliodes Forster, 1964, the only representative of the mega-diverse mostly Andean Pedaliodes complex lineage in the Brazilian Atlantic Forest, is revised. Prior to this study, four species were known, P. phanias (Hewitson, 1862), P. granulata (Butler, 1868), P. amussis (Thieme, 1905) and P. exul (Thieme, 1905). Here, a further six are described, all from SE Brazil, expanding to 10 the number of species in this genus. Lectotypes are designated for P. phanias, P. granulata and P. amussis. The genus is most diverse in the Serra da Mantiqueira (São Paulo, Rio de Janeiro, Minas Gerais) and in the Serra Geral (Paraná, Santa Catarina) with seven species occurring in both ranges. Praepedaliodes phanias is the most widespread species and the only one found in the western part of the Atlantic Forest; only this species and P. duartei Dias, Dolibaina & Pyrcz n. sp. occurring to near sea level. Other species, P. zaccae Dolibaina, Dias & Pyrcz n. sp., P. francinii Freitas & Pyrcz n. sp., P. sequeirae Pyrcz, Dias & Dolbaina n. sp., P. landryi Pyrcz & Freitas n. sp. and P. pawlaki Pyrcz & Boyer n. sp. are strictly montane and the highest species richness is reached at 1400–1800 m. One species, P. sequeirae n. sp., is a narrow endemic found only at timberline in the Agulhas Negras massif above 2300 m. Immature stages are described for two species, P. phanias and P. landryi n. sp. Molecular data (barcode region of cytochrome oxidase, subunit I) and adult morphology, including male and female genitalia, support the genus as monophyletic, belonging to a predominantly Andean clade of the Pedaliodes Butler, 1867 complex. Morphological evidences, in particular female genitalia comparative analysis, indicate the genera Physcopedaliodes Forster, 1964 and Panyapedaliodes Forster, 1964 as possibly the closest relatives to Praepedaliodes. Molecular data are inconclusive in this respect.  相似文献   

7.
Eight species of Dactylogyridae were collected from the gills of the pintado-amarelo Pimelodus maculatus Lacépède in the Rio São Francisco in Brazil: Ameloblastella paranaensis (França, Isaac, Pavanelli &; Takemoto, 2003) Mendoza-Franco &; Scholz, 2009, A. satoi n. sp., Ameloblastella sp., Demidospermus armostus Kritsky &; Gutiérrez, 1998, D. cf. bidiverticulatum (Suriano &; Incorvaia, 1995) Kritsky &; Gutiérrez, 1998, D. ichthyocercus n. sp., D. paravalenciennesi Gutiérrez &; Suriano, 1992 and D. uncusvalidus Gutiérrez &; Suriano, 1992. Two new species, A. satoi n. sp. and D. ichthyocercus n. sp., are described, and A. paranaensis is redescribed. The Rio São Francisco represents new geographical records for the five previously described dactylogyrid species.  相似文献   

8.
Aloculibothrium dasyatii n. gen. n. sp. is described from the spiral intestine of Dasyatis sephen Forsskal, 1775 captured at Digha coastal waters, Bay of Bengal, India. This species is placed under the famil Onchobothriidae (Braun, 1900) and erected a new genus Aloculibothrium to accommodate this specimen. The body is 24.22–36.58 mm long and with 310–325 proglottids; scolex rectangular with two parts; anterior bearing four bothridia with paired bifurcated hooks, divided into inner and outer prong and posterior with fleshy collar. The cestode has been compared with all the existing twelve different valid genera under the family Onchobothriidae but to accommodate the present specimens a new genera Aloculibothrium is erected.  相似文献   

9.
A new species of moray eel, Diaphenchelys dalmatian is described based on five specimens [289.8–503.0 mm total length (TL)] collected from the western coast of peninsular Thailand and the Gulf of Thailand. It can be easily distinguished from Diaphenchelys pelonates McCosker and Randall 2007, another species of the genus Diaphenchelys McCosker and Randall 2007, by its coloration (ground color white with brown dalmatian-like spots vs. brown with pale vermiculate pattern). The present new species also differs from D. pelonates in its longer tail (62.0–64.6% TL vs. 59.6–61.5%), fewer infraorbital pores along upper lip (three vs. four), fewer mandibular pores (five vs. six or seven), and fewer vertebral counts (preanal vertebrae 43–46 vs. 55–58; total 126–131 vs. 153–155). Diaphenchelys is closely similar to the genus Strophidon McClelland 1844 in the shape of neurocranium, the elongate body, low vertical fins, eye location, jaw shape, and presence of inner mandibular teeth. However, both differ in the vertebral counts (126–155 in Diaphenchelys vs. 164–208 in Strophidon) and coloration (prominent pattern vs. uniform).  相似文献   

10.
The monotypic genus Spathebothrium Linton, 1922 contains the only known species Spathebothrium simplex Linton, 1922. In this paper Spathebothrium vivekanandai sp.n. is described and illustrated. The specimen was obtained from the intestine of a freshwater fish Channa striatus which was collected from Basirhat, North 24 Parganas, West Bengal, India. The species is characterized by a small scolex, rounded anteriorly; presence of neck; genital pores irregularly or regularly alternate and U-shaped ovary. In addition to these characters, absence of vaginal sphincter and absence of seminal receptacle differentiates the present species from the earlier described one. The genus Spathebothrium Linton, 1922 is being reported for the first time from West Bengal, India.  相似文献   

11.
This article presents a corpus study of over 16,000 tokens of -er nominalizations on 62 verbal bases that were extracted from the Corpus of Contemporary American English and the British National Corpus. We show that an individual -er nominal can often be given a range of modal and aspectual readings and that a number of factors influence the availability of different readings for -er nominals, including verb type, syntactic context (verb tenses, adverbs), and encyclopedic information. On the basis of these data, we argue, contra Cohen (2016), that the core meaning of the affix -er (as in writer, printer, etc.) cannot be that of a dynamic modal. We show that neither Cohen’s (2016) analysis nor syntactic analyses such as that of Alexiadou and Schäfer (2010) can account for the range of readings we find. We conclude by sketching one possible analysis in terms of the Lexical Semantic Framework of Lieber (2004, 2016) that postulates underspecified lexical representations of the -er nominals and resolution of underspecification in context.  相似文献   

12.
The genus Djombangia Bovien, 1926 is a monotypic genus with only one valid species Djombangia penetrans Bovien, 1926 under it. In this paper Djombangia mannai sp.n. obtained from the intestine of a siluriform fresh water fish Clarias batrachus Linnaeus, 1758 from Diamond Harbour, South-24 Parganas, West Bengal, India is described and illustrated. The species is characterized by a small, globular scolex with spherical apical organ; body without transverse grooves; absence of neck; absence of seminal receptacle and 300–350 testes that differentiates it from the only known species under this genus.  相似文献   

13.
A taxonomic review of the northwestern Pacific Ocean members of the Ostichthys japonicus complex (Holocentridae: Myripristinae), defined by 3.5 scale rows between the lateral line and spinous dorsal-fin base, recognized three valid species: Ostichthys alamai sp. nov., Ostichthys hypsipterygion Randall, Shimizu and Yamakawa 1982 and Ostichthys japonicus (Cuvier in Cuvier and Valenciennes 1829). Ostichthys alamai, based on 10 specimens (118–179 mm SL) from Panay Island, the Philippines and Sulawesi, Indonesia, is similar to O. hypsipterygion in having longitudinal rows of white spots laterally on the body, but has 17 or 18 (modally 17) pectoral-fin rays [vs. 15 or 16 (15) in the latter], the last dorsal-fin spine fused to the first dorsal-fin soft ray (vs. spine and ray separated), and no white blotch on the pectoral-fin base (vs. white blotch present). It differs from O. japonicus, also occurring in the Philippines, in having relatively longer dorsal- and anal-fin spines, a greater number of well-developed long spinules on the body scales, and rows of white spots laterally on the body (vs. generally absent). Detailed comparisons of O. alamai with other members of the complex are made, and revised diagnoses given for O. hypsipterygion and O. japonicus. Ostichthys sheni Chen, Shao and Mok 1990 and Holotrachys major Whitley 1950 are both regarded as junior synonyms of O. japonicus.  相似文献   

14.
A taxonomic review of the Dendrochirus brachypterus complex resulted in the recognition of five species, including Dendrochirus barberi (Steindachner 1900), Dendrochirus bellus (Jordan and Hubbs 1925), Dendrochirus brachypterus (Cuvier in Cuvier and Valenciennes 1829), Dendrochirus hemprichi sp. nov. and Dendrochirus tuamotuensis Matsunuma and Motomura 2013. The complex is defined as having usually 9 dorsal-fin soft rays, usually 5 anal-fin soft rays, 17–20 (rarely 20) pectoral-fin rays, no ocellated spots on the soft-rayed portion of the dorsal fin and usually 2 (sometimes none) barbels on the snout tip. Dendrochirus barberi, known from the Hawaiian Islands and Johnston Atoll, is characterized by usually 18 pectoral-fin rays, a relatively high number of scale rows in the longitudinal series (modally 51 vs. 39–49 in other species) and mottled markings on the pectoral fin in large specimens. Dendrochirus bellus, restricted to the northwestern Pacific Ocean from the South China Sea north to southern Japan, is characterized by usually 17 pectoral-fin rays, a relatively low number of scale rows in the longitudinal series (modally 38 vs. 44–51 in other species), and the absence of skin flaps on the orbit surface and uppermost preopercular spine base. Dendrochirus tuamotuensis, recorded only from the Tuamotu Archipelago, is characterized by 19 pectoral-fin rays, the posterior margin of the pectoral fin strongly notched, and a relatively shallow and narrow head and body. Dendrochirus hemprichi sp. nov. is distributed in the western Indian Ocean, including the Red Sea. Although previously confused with a closely related congener (D. brachypterus, known from the northern and eastern Indian Ocean and western Pacific), D. hemprichi can be distinguished from the former by having fewer scale rows between the last dorsal-fin spine base and lateral line, and between the sixth dorsal-fin spine base and lateral line [4–7 (5) in D. hemprichi vs. 5–7 (6) in D. brachypterus, in both cases], a slightly greater interorbital width at the mid-orbit [5.5–10.7 (mean 7.8) % SL vs. 4.5–8.9 (6.8) % of SL] and at preocular spine base [4.4–9.1 (6.6) % SL vs. 3.5–7.8 (5.7) % of SL], and slightly shorter posteriormost (usually 13th) dorsal-fin spine length [11.8–19.9 (15.3) % SL vs. 13.3–21.3 (17.2) % of SL]. Moreover, D. hemprichi tends to have relatively more spinous points on the head spines and ridges, compared with D. brachypterus. Notwithstanding the morphological similarity between the two species, an obvious genetic difference was observed between D. hemprichi and D. brachypterus. Dendrochirus chloreus Jenkins 1903 and Dendrochirus hudsoni Jordan and Evermann 1903 were synonymized under Pterois barberi, as in some previous studies. Scorpaena koenigii Bloch 1789 was regarded as conspecific with D. brachypterus, which it predated. However, the former name should be suppressed under Reversal of Precedence.  相似文献   

15.
The genus Anonchotaenia Cohn, 1900 contains 23 valid species. In this paper Anonchotaenia adhiraji sp.n. obtained from the intestine of a bird Hypsipetes madagascarensis commonly known as black bulbul from Bomdila in Dirang district of Arunachal Pradesh, India is described and illustrated.The species is characterized by a large unarmed, square-shaped scolex; testes 7–8 in number arranged in two lateral groups and a voluminous paruterine organ that differentiates it from the rest of the described species in the genus. This is also the first report of the genus Anonchotaenia Cohn, 1900 from Arunachal Pradesh, India.  相似文献   

16.
Drosophila, a dipteran insect, has been found to be the best biological model for different kinds of studies. D melanogaster was first described by Meigen in 1830, is most extensively studied species of the genus Drosophila and a number of investigations employing this species have been documented in areas such as genetics, behaviour, evolution, development, molecular biology, ecology, population biology, etc. Besides D. melanogaster, a number of other species of the genus Drosophila have also been used for different kinds of investigations. Among these, D. ananassae, a cosmopolitan and domestic species endowed with several unusual genetic features, is noteworthy. Described for the first time from Indonesia (Doleschall 1858), this species is commonly distributed in India. Extensive research work on D. ananassae has been done by numerous researchers pertaining to cytology, genetics, mutagenesis, gene mapping, crossing-over in both sexes, population and evolutionary genetics, behaviour genetics, ecological genetics, sexual isolation, fluctuating asymmetry, trade-offs etc. Genome of D. ananassae has also been sequenced. The status of research on D. ananassae at global level is briefly described in this review. Bibliography on this species from different countries worldwide reveals that maximum contribution is from India.  相似文献   

17.
A systematic theoretical investigation on cobalt lithium clusters LinCo [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12] was performed with a DFT approach. The location of global minima and structural evolution were carried out using the partical swarm optimization method. Li6Co is the transition structure in going from low-coordinated structures to three-dimensional torispherical structures with a cobalt atom enclosed by lithium atoms. Maxima of ?2 E and E b for LinCo were found at n?=?3, 6, 8, 10, indicating that these clusters possess higher relative stability than their neighbors. In comparison with small clusters, n?=?1–6, the greater electron transfer from Li-2s to Co-3d within cage-like clusters LinCo (n?=?7–12) strengthens the bonding effect between Lin and Co, which is reflected in the Wiberg bond index of Co and atomic binding energy analysis. AdNDP analysis verified the presence of both Lewis bonding elements (1c–2e objects) and delocalized bonding elements (6c–2e, 9c–2e and 10c–2e bonds). It is hoped that this theoretical work will provide favorable information to help understand the influence of dopant transition metal atoms on the properties of lithium-based materials.  相似文献   

18.
The Coburg Sandstone member of the Hassberge Formation, Middle Keuper, Carnian, Upper Triassic, in the Germanic Basin of Central Europe contains spinicaudatan branchiopods which considerably broaden the known spectrum and provide important data on the phylogenetic history and intercontinental correlation of this systematic group. The spinicaudatan fauna for this lithostratigraphic unit is described in detail and includes Euestheria kozuri sp. nov., E.? sp. nov. A, Gregoriusella striatula sp. nov., Laxitextella freybergi Kelber and Kozur in Kozur and Weems, 2007, L. dorsorecta (Reible, 1962), and Laxitextella? sp. A. Additional discussions deal with Euestheria multicostata (Geyer, 1987), E. winterpockensis (Bock, 1953a), Laxitextella laxitexta (Sandberger in Jones, 1890), Laxitextella multireticulata (Reible, 1962), and “Laxitextella? hausmanni (Schmidt, 1938),” as well as problems with (sub)global zonations that are based on spinicaudatans and suggested to be of Carnian and Norian age.  相似文献   

19.
Two western Pacific triplefins, Enneapterygius fuscoventer Fricke 1997 and E. howensis Fricke 1997 (Perciformes: Tripterygiidae), are similar to each other in sharing 15–19 (usually 17) notched lateral-line scales and the mandibular pore formula 3–5 + 1 + 3–5 (usually 4 + 1 + 4), in addition to similar coloration, viz. body with four vertical bands, the first and second forked ventrally, dorsal-fin membrane semi-transparent, anal fin entirely blackish, and caudal fin blackish with a semi-transparent margin. These species have previously been known only from preserved specimens. Examination of additional specimens plus color photographs of males and females of both species when fresh, and comparisons with type specimens resulted in several features, including coloration and counts of second dorsal-fin spines, anal-fin soft rays, pored lateral-line scales and longitudinal scale rows, being regarded as new diagnostic characters. Enneapterygius fuscoventer and E. howensis have been newly recorded from southern Japan and coastal eastern Australia, respectively.  相似文献   

20.
The monotypic genus Teskeyellus was described for T. hirsuticornis Philip & Fairchild 1974, from Mexico. After more than 40 years, another species is described in the genus, T. cyanommatus sp. nov., based on two females and one male specimens from Amazon basin. The type specimens of T. hirsuticornis were studied and we concluded that there are enough similarities to include the new species in Teskeyellus.  相似文献   

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