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1.
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   

2.
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   

3.
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   

4.
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   

5.
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   

6.
7.
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   

8.
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   

9.
Within the fossil collection from the Sandelzhausen Lagerstätte in the Upper Freshwater Molasse near Mainburg, Germany, are remains of the schizotheriine chalicothere Metaschizotherium bavaricum, von Koenigswald, 1932. This new material includes elements from a large part of the body, and allows the dentition and postcranial skeleton of Metaschizotherium to be described in detail for the first time. At approximately 16 Ma (MN5), M. bavaricum is now the best-known Early and Middle Miocene European schizotheriine and is important for comparative studies. It differs to some degree from earlier Miocene (MN2–MN4) European material attributed to Moropus sp. or Metaschizotherium wetzleri (Kowalewsky, 1873) and to a larger degree from the Late Miocene species Ancylotherium pentelicum (Gaudry and Lartet, 1856). At Sandelzhausen, M. bavaricum apparently lived in a moist forested environment, where it probably fed on leaves, fruit, and seeds. Members of the Chalicotheriinae, such as Anisodon and Chalicotherium, are not found at Sandelzhausen and may not have been present in Europe at this time. M. bavaricum, like other Schizotheriinae, did not have the bizarre gorilla-like proportions of the Chalicotheriinae. Instead, its general body proportions resemble those of contemporary schizotheriine chalicotheres on other continents, for example, Moropus from North America. M. bavaricum is slightly smaller than the type species of Metaschizotherium, M. fraasi von Koenigswald, 1932 (MN6–MN7) and differs from it in small ways that are still being explored as variation within and differences between these species are clarified. The schizotheriine chalicothere from La Grive St.-Alban (France) referred to M. fraasi by von Koenigswald (Palaeontographica, Beitrage zur Naturgeschichte der Vorzeit 8:1–24, 1932) and Viret (Nouvelles Archives Musée d’Histoire Naturelle de Lyon 6:53–81, 1961) should be restudied and referred to a different taxon.  相似文献   

10.
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   

11.
A new species of damselfish, Abudefduf nigrimargo (Pomacentridae), is described on the basis of six specimens (91.8–119.5 mm standard length; SL) from Taiwan. Although similar to A. caudobimaculatus Okada and Ikeda 1939, A. saxatilis (Linnaeus 1758), A. troschelii (Gill 1862) and A. vaigiensis (Quoy and Gaimard 1825) in having five dark bands on the lateral surface of the body with yellowish interspaces dorsally, the new species can be distinguished from the others by the following combination of characters: 18–19 (mode 19) pectoral-fin rays; 20–23 (22) tubed lateral-line scales; 7–8 (7)?+?14–16 (16)?=?21–24 (23) gill rakers; relatively greater body depth and longer pectoral-fin length [57.3–60.8% (mean 59.0%) of SL and 36.8–40.8% (38.5%) of SL, respectively]; 5 scale rows on cheek; scales on suborbit, usually continuous over basal area of lacrimal; many scales on anteroventral region of head; scale covering on preopercle and interopercle continuous; scales on dorsal and lateral body surfaces with blackish margin (indistinct in subadult), second and third black bands on body not extending dorsally onto membranes of spinous dorsal fin; anterior and upper margins of fourth black band usually level with sixth dorsal-fin soft ray base and not extending onto small scales on the dorsal-fin base, respectively; and caudal-fin base without black spots.  相似文献   

12.
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   

13.
The transmembrane topology of subunit N from E. coli Complex I has been investigated. Chemical labeling of mono-substituted cysteine mutants was carried out in inverted membrane vesicles, and in whole cells, using 3-N-maleimidyl-propionyl biocytin (MPB). The results support a model of 14 transmembrane spans with both termini in the periplasm, and are consistent with the models of subunits L, M and N from the crystal structure of the membrane arm of the E. coli Complex I (Efremov et al. (2010) Nature 465, 441–445). In particular, the results do not support an unusual cytoplasmic localization of two likely transmembrane regions, as proposed in previous studies (Mathiesen and Hägerhäll (2002) Biochim Biophys Acta 1556, 121–132; Torres-Bacete, et al. (2009) J Biol Chem 284, 33062–33069).  相似文献   

14.
The oldest terrestrial darkling beetle of the opatrine lineage, Palaeosclerum pohli gen. et. sp. nov. (subfamily Tenebrioninae) is described from the Middle Paleocene of Menat (France). The complex of characters, combining the peculiar shape of body (robust, adapted to a fossorial lifestyle), structure of fossorial protibia, 5-segmented antennal club demonstrates a considerable similarity of the new genus to the extant representatives of the ‘sclerina’ generic group of the subtribe Opatrina. Palaeosclerum gen. nov. is compared with recent genera Sclerum Dejean, 1834, Platynosum Mulsant and Rey, 1859 and Eurycaulus Fairmaire, 1868.  相似文献   

15.
16.
Tamás Halm 《Morphology》2018,28(4):359-396
The non-possessive uses of possessive morphology in Uralic languages have been a topic of intense debate (Fraurud 2001; Nikolaeva 2003; Gerland 2014; Janda 2015; É. Kiss and Tánczos to appear). In this paper, I focus on a special use of the poss.3sg suffix in Hungarian constructions such as a hülyéje (the stupid-poss.3sg): lit. ‘its stupid’, meaning ‘that total idiot’. My main claim is that this suffix is an affective demonstrative suffix (Lakoff 1974; Liberman 2008; Potts and Schwarz 2010), and that it has developed as a result of grammaticalization from a full-fledged possessive construction of the form a világ hülyéje (the world stupid-poss.3sg): lit. ‘the world’s stupid’, meaning: ‘the biggest idiot in the world’. I will show that this gradual process can be reconstructed fairly accurately using historical and contemporary corpora. I also claim that this grammaticalization pathway is very natural as it is based on a set-element relationship which is often expressed by possessive constructions cross-linguistically. I also identify two parameters which facilitate this grammaticalization process: the availability of (silent) pro possessors and the lack of gender agreement on the possessive suffix. Since Uralic languages in general have these parameters, I will argue that this grammaticalization pathway should at least be considered as one of the possible sources of the demonstrative (and definiteness marking) uses of poss.3sg suffixes in Uralic languages. Finally, my results are also an important contribution to the debate on whether demonstratives can be derived from other functional elements through grammaticalization (Plank 1979; Traugott 1982; Himmelmann 1997).  相似文献   

17.
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   

18.
Comma-free codes constitute a class of circular codes, which has been widely studied, in particular by Golomb et al. (Biologiske Meddelelser, Kongelige Danske Videnskabernes Selskab 23:1–34, 1958a, Can J Math 10:202–209, 1958b), Michel et al. (Comput Math Appl 55:989–996, 2008a, Theor Comput Sci 401:17–26, 2008b, Inf Comput 212:55–63, 2012), Michel and Pirillo (Int J Comb 2011:659567, 2011), and Fimmel and Strüngmann (J Theor Biol 389:206–213, 2016). Based on a recent approach using graph theory to study circular codes Fimmel et al. (Philos Trans R Soc 374:20150058, 2016), a new class of circular codes, called strong comma-free codes, is identified. These codes detect a frameshift during the translation process immediately after a reading window of at most two nucleotides. We describe several combinatorial properties of strong comma-free codes: enumeration, maximality, self-complementarity and \(CF^3\)-property (comma-free property in all the three possible frames). These combinatorial results also highlight some new properties of the genetic code and its evolution. Each amino acid in the standard genetic code is coded by at least one strong comma-free code of size 1. There are 9 amino acids \(S=\{Asn,Asp,Gln,Gly,Lys,Met,Phe,Pro,Trp\}\) among 20 such that for each amino acid from S, its synonymous trinucleotide set (excluding the necessary periodic trinucleotides \(\{AAA,CCC,GGG,TTT\}\)) is a strong comma-free code. The primeval comma-free RNY code of Eigen and Schuster (Naturwissenschaften 65:341–369, 1978) is a self-complementary \(CF^3\)-code of size 16. Furthermore, it is the union of two strong comma-free codes of size 8 which are complementary to each other.  相似文献   

19.
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   

20.
Early Permian continental deposits include a large number of localities containing anthracosiid-like non-marine bivalves traditionally assigned to Anthraconaia Trueman and Weir, 1946, Palaeanodonta Amalitzky, 1895, and Palaeomutela Amalitzky, 1892. In most cases, these classifications are only tentative due to insufficient preservation in which the shells are missing their main characteristics: the ligament and the hinge. Non-marine bivalves from the Early Permian Upper Pospelovka Subformation of Russky Island (South Primorye, Far East Russia), described here as Hypoanthraconaia gen. nov., differ morphologically from the above genera by a set of external features including the initial shell, the mode of intersection of the growth lines with the dorsal margin, and the details of the sculpture. Hypoanthraconaia gen. nov. shows the most external similarity with “atypical” anthracosiid-like morphotypes of Anthraconaia that are widespread in the Late Pennsylvanian and Early Permian of eastern North America, and the Stephanian and Early Permian Lower Rotliegend of northwestern Europe. On this basis, the new genus is conventionally assigned to the family Naiaditidae Scarlato and Starobogatov, 1979.  相似文献   

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