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1.
The carotenoids of 12 species of Siluriformes fishes (eight families) were investigated from a comparative biochemical point of view. The patterns of carotenoids in catfishes belonging to the family Siluridae were quite different from those of the other seven families of catfishes (Bagridae, Amblycipitidae, Clariidae, Plotosidae, Ictaluridae, Callichthyidae and Malapteruridae). 7, 8-Dihydro-beta-carotene; 7, 8, 7', 8'- and 7, 8, 9, 10-tetrahydro-beta-carotene; (3R)-7', 8'-dihydro-beta-cryptoxanthin; 7, 8-dihydrolutein A; 7, 8-dihydrolutein B; parasiloxanthin; 7', 8'-dihydroparasiloxanthin; and 4 or 4'-hydroxyparasiloxanthin were characteristic carotenoids found in only one family, Siluridae, and these carotenoids accounted for 24-60% of total carotenoids. In catfishes belonging to the other seven families except Siluridae, the carotenoid patterns were very similar and the most predominant carotenoid was zeaxanthins (23-56%).  相似文献   

2.
A numerical cladistic analysis, based on 23 terminal groups and 63 morphological characters, was done to infer phylogenetic relationships within the Eurasian catfish family Siluridae. Nine hundred and forty-five equally most parsimonious trees (134 steps, consistency index 0.634) were found that differ in their resolutions of four polychotomies. Strict consensus of these trees includes ten internal nodes, does not support monophyly of Silurus, Ompok and Kryptopterus , as usually defined, and offers ambiguous support for monophyly of Wallago. Silurus and Kryptopterus are each composed of two non-sister group clades, and Ompok is composed of at least two such clades. Heuristic searches constrained by monophyly of Silurus, Ompok or Kryptopterus yielded trees five or six steps longer than the shortest trees free of constraints. The strict consensus also infers a basal dichotomy that separates the Siluridae into a temperate Eurasian clade with about 20 nominal species and a subtropical/tropical south and southeast Asian clade with about 75 nominal species. The distributions of these clades overlap in a relatively narrow region of east Asia. A heuristic search for trees 1 step longer than the shortest trees yielded 253890 trees. A strict consensus of these trees also infers a basal dichotomy between the above-mentioned clades. This analysis revealed four additional putative synapomorphies of the Siluridae, pending further resolution of the family's outgroup relationships.  相似文献   

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从细胞色素b基因序列变异分析中国鲇形目鱼类的系统发育   总被引:18,自引:0,他引:18  
采用PCR技术获得中国鲇形目鱼类11科24属27个代表种类细胞色素b基因1138bp全序列,比较分析了来自北美洲、非洲的部分鲇形目鱼类同一基因序列,并选取脂鲤目、鲤形目和鲱形目鱼类作外类群,采用Bayesian方法和最大简约法(MP)构建分子系统树。结果表明:(1)鲇形目鱼类细胞色素b基因序列中,与脂鲤目、鲤形目以及鲱形目鱼类相比存在3bp的缺失;(2)鲇形目鱼类各科代表种类形成一单系群;(3)两种建树方法均支持铫科、粒鲇科和钝头鮠科形成一单系群;而胡子鲇科、刀鲇科、海鲇科、鮰科、长臀鮠科、鲢科、鲇科、棘脂鲿科、鲿科形成一大的单系群;但鳗鲇科的系统位置两种建树方法没有取得一致结果;而其中长臀鲍科与北美的鮰科形成姐妹群,胡子鲇、鮰科、鲇科、鲿科和鮡科是较明显的单系群。  相似文献   

5.
《Comptes Rendus Palevol》2007,6(5):321-326
A fossil slender mola (Tetraodontiformes, Molidae) is described from the Miocene (Messinian) of the Chelif Basin, Algeria. The material consists of a single individual largely incomplete, solely represented by part of the anal-fin pterygiophores complement. The specimen is referred to the genus Ranzania because of the elongate slender morphology and thick and well-ossified consistence of the bones, which are also characterized by a dense and moderately spongy texture. However, it has been left unnamed, awaiting more complete and better-preserved material. This is the first occurrence of the genus Ranzania, and more generally of the family Molidae, in the Messinian of the Mediterranean. It provides new data about the structure and diversity of Miocene pelagic fish communities of the Chelif Basin.  相似文献   

6.
《Journal of morphology》2017,278(6):848-864
The median fins in extant actinopterygians are the product of millions of years of evolution. During this time, different developmental patterns for the dorsal and anal fins emerged leading to a high variation in median fin morphology and ontogeny. In this study, the development of anal and dorsal fins in atheriniforms is described and its consequences for the current phylogenetic hypothesis are discussed. Developmental series of five atheriniform species were investigated using clearing and staining as well as antibody staining. The skeletal elements of the second dorsal fin and the anal fin emerge in a bidirectional pattern. The first dorsal fin, however, arises separately in front of the second dorsal fin after this one is almost completely formed. The pterygiophores of the first dorsal fin, including the interdorsal pterygiophores, develop from caudal to rostral, but the fin‐spines of the first dorsal fin form in the opposite direction. This new mode of fin development has been found in all examined atheriniform species with two dorsal fins. Several morphological characters of atheriniforms, including interdorsal pterygiophores, are also found in one other taxon: the Mugiliformes. Thus, several dorsal fin characteristics may provide evidence for a closer relationship of these two taxa.  相似文献   

7.
Tetraodontiformes (pufferfishes and kin) is a taxonomically and structurally diverse, widely‐distributed clade of acanthomorphs, whose members often serve as models for genomics and, increasingly, macroevolutionary studies. Morphologically disparate Palaeogene fossils suggest considerable early experimentation, but these flattened specimens often preserve limited information. We present a three‐dimensionally preserved beaked tetraodontiform from the early Eocene (c. 53 Ma) London Clay Formation, UK. Approximately coeval with the oldest crown tetraodontiforms, ?Ctenoplectus williamsi gen. et sp. nov. presents an unprecedented combination of characters, pairing a fused beak‐like dentition with prominent dorsal‐fin spines that insert atop transversely‐expanded pterygiophores roofing the skull. Bayesian total‐evidence tip‐dating analysis indicates that ?Ctenoplectus represents the sister lineage of Triodontidae and highlights considerable levels of homoplasy in early tetraodontiform evolution. According to our dataset, rates of morphological character evolution were elevated at the origin of crown Tetraodontiformes, especially within gymnodonts, but declined after the principal body plans were established. Such ‘early burst’ patterns are regarded as a hallmark of adaptive radiations, but are typically associated with diversification at smaller spatiotemporal scales. However, denser sampling of Neogene and Recent taxa is needed to confirm this pattern.  相似文献   

8.
External and internal morphological characters of the holotype of Enobarbus maculatus were examined and compared with those of other cobitid species to verify whether Enobarbus is a distinct genus. Analyses of radiographs demonstrated that the neural spines and the pterygiophores of the dorsal fin are of irregular shape, often doubled, reduced or bent. The holotype of E. maculatus bears an ossified structure on the last pectoral-fin ray, a structure otherwise known only from males of the genus Lepidocephalichthys. In Lepidocephalichthys, the shape of the ossified structure is species-specific, and the structure of Enobarbus is very similar to that of Lepidocephalichthys thermalis, the only other known species of the family Cobitidae occurring at the type locality of Enobarbus. Furthermore, the cranial and the axial skeleton of E. maculatus is similar to that of L. thermalis, except for the pterygiophores and the neural spines, that are strongly malformed in Enobarbus. In general, the results presented here show that the genus Enobarbus shares the most important characters (thickening of last two pectoral-fin rays in males, structure of swimbladder capsule, shape of neurocranium and suborbital spine) with Lepidocephalichthys and that its long dorsal fin is correlated with strong malformations of the vertebral column and the fin ray insertions. Consequently, the only known specimen of Enobarbus is most likely a teratological male of L. thermalis, and Enobarbus is a junior synonym of Lepidocephalichthys.  相似文献   

9.
The poorly known Haloragaceae R. Br. (Saxifragales) are highly diverse in habit (small trees to submerged aquatics) and labile in floral merosity (2-4), both uncommon among the core eudicots. This family has a cosmopolitan distribution, but taxonomic diversity is concentrated in Australia. An explicit phylogenetic approach has not previously been utilized to examine relationships or character evolution in this family. We used molecular evidence from nrDNA ITS and cpDNA trnK and matK regions under both Bayesian and parsimony analyses to address phylogenetic relationships. Combined molecular analyses defined a monophyletic Haloragaceae with the woody genera (Haloragodendron, Glischrocaryon) sister to the rest. Relationships among many genera were well resolved, with genera as currently delimited generally well supported, although there were notable exceptions; a new genus (Trihaloragis) is recognized, and the aquatic genus Meionectes is again distinct from Haloragis. Three new species combinations are also recognized. There are multiple (two or three) origins of the submerged aquatic habit in the family and potentially an intermediate reversal to the terrestrial habit, neither previously demonstrated in a core eudicot family using an explicit phylogenetic hypothesis. Ancestral character analyses suggest two origins of trimerous flowers and multiple reductions to dimerous flowers throughout Haloragaceae.  相似文献   

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The present communication reports an endangered catfish of the family Siluridae, Pterocryptis barakensis (Vishwanath & Sharma) for the first time outside its type locality from Brahmaputra drainage. The specimens were collected from the River Tissa, Longding district, Arunachal Pradesh foothills of Himalayan region of North East India. The current study describes morphometric and molecular characteristics of this endangered species.  相似文献   

12.
Stability and procured instability characterize two opposing types of swimming, steady and maneuvering, respectively. Fins can be used to manipulate flow to adjust stability during swimming maneuvers either actively using muscle control or passively by structural control. The function of the dorsal fins during turning maneuvering in two shark species with different swimming modes is investigated here using musculoskeletal anatomy and muscle function. White‐spotted bamboo sharks are a benthic species that inhabits complex reef habitats and thus have high requirements for maneuverability. Spiny dogfish occupy a variety of coastal and continental shelf habitats and spend relatively more time cruising in open water. These species differ in dorsal fin morphology and fin position along the body. Bamboo sharks have a larger second dorsal fin area and proportionally more muscle insertion into both dorsal fins. The basal and radial pterygiophores are plate‐like structures in spiny dogfish and are nearly indistinguishable from one another. In contrast, bamboo sharks lack basal pterygiophores, while the radial pterygiophores form two rows of elongated rectangular elements that articulate with one another. The dorsal fin muscles are composed of a large muscle mass that extends over the ceratotrichia overlying the radials in spiny dogfish. However, in bamboo sharks, the muscle mass is divided into multiple distinct muscles that insert onto the ceratotrichia. During turning maneuvers, the dorsal fin muscles are active in both species with no differences in onset between fin sides. Spiny dogfish have longer burst durations on the outer fin side, which is consistent with opposing resistance to the medium. In bamboo sharks, bilateral activation of the dorsal in muscles could also be stiffening the fin throughout the turn. Thus, dogfish sharks passively stiffen the dorsal fin structurally and functionally, while bamboo sharks have more flexible dorsal fins, which result from a steady swimming trade off. J. Morphol. 274:1288–1298, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

13.
The osteology of Florenciella lugubris is described. F. lugubris is attributed to the family Epigonidae on the basis of specific characters of structure of orbital bones, skull, jaws and hyoid, presence of three principal spines on operculum, contact of pterygiophores of dorsal fins, 10 + 15 vertebrae, extension of the lateral line onto the caudal fin, structure of the first hemapophysis and interhaemale, caudal skeleton, etc. At the same time, Florenciella is more advanced in comparison with Epigonus having such characters as presence of enlarged, directed to sides and/or forward symphyseal teeth in jaws, of finely and densely denticulatd edges of infraorbitalia 2–8 and of the orbiral edge of frontale, and fontanelle in bulla otica and having specific traits of denticulation of opercular bones, having no separated distal element in the free pterygiophore between the first and second dorsal fins, having modified scales, etc. The related genera Florenciella and Rosenblattia may be synonyms.  相似文献   

14.
A study of laboratory-reared larvae of Solea solea (Soleidae) and Scophthalmus maximus (Scophthalmidae) indicated that the epicranial portion of the dorsal fin results from the anterior displacement of proximal pterygiophores during ontogeny. The adult epicranial formula is attained early during ontogeny, and the anterior displacement is finalized after the passage of the migrating eye. In both species, the first two proximal pterygiophores fuse to form an erisma that is particularly long and well-developed in Solea. Moreover, in Solea, the neural spine of the second abdominal vertebra curves over the otic region, and the neural arch of the first vertebra remains incomplete. Received: August 3, 2000 / Revised: August 10, 2001 / Accepted: October 12, 2001  相似文献   

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16.
The osteology is described of Bathysphyraenops simplex, and its close relationship is demonstrated with genera Howella and Pseudohowella. These three genera should be classified into separate family Howellidae characterized by the specific structure of the bones of the infraorbital series, the absence of the hyomandibular process of metapterygoideum, and the reduction of the anterior plate of hyomandibulare, the absence of contact of pterygiophores of the 1st and 2nd dorsal fins, presence in front of the second dorsal fin of a free pterygiophore having no distal element, 16 caudal vertebrae, the characteristic structure of scales, and some other characters. The osteological distinctions of Bathysphyraemops simplex from Howella sherborni found for the first time are small and the author believes that some of them may make a case of interspecies variation within these genera. The revised diagnosis of the family Howellidae is presented. The status of the fossil genera Synagropoides and Cottopsis is discussed. They may become representatives of this family.  相似文献   

17.
The present study describes the condition factor, length‐weight and length‐length relationships for an endangered freshwater fish species Ompok pabda (Hamilton) of the family Siluridae from the River Gomti in Northern India. The values of regression parameter b ranged from 2.81 to 3.32 (r2 > 0.90). During the pre‐monsoon, the allometric coefficient b of the LWR was close to isometric value (b = 3.08) allometric (b = 2.87), although it suggested negative allometric growth in monsoon periods while positive growth in post‐monsoon. The condition factor values ranged from 0.672 to 0.744. Results of the present study could be useful to help in conservation and sustainable fisheries management of this endangered species.  相似文献   

18.
Spencer  A. N. 《Hydrobiologia》1991,216(1):565-571
A family of peptides with the carboxy-terminus Arg-Phe-amide has been localized to specific subpopulations of neurons in every cnidarian species examined. These neurons are typically sensory in character or are associated with smooth muscle. Although a transmitter role for these peptides has been suggested for anthozoans at neuromuscular synapses, no such evidence is available for hydrozoans. Instead there is evidence that RF-amides can be modulators of neuronal activity which takes the form of a biphasic (inhibitory then excitatory) response in vivo, while in vitro only the inhibitory response is seen. Voltage clamp studies of identified motor neurons showed large, transitory outward currents when Pol-RF-amide peptide was applied.  相似文献   

19.
A study of nine cyprinid and six catostomid species focused on the early ontogeny of supraneurals and neural arches of the Wehcrian apparatus. These elements chondrify during the mesolarval stage, and there is strong temporal correlation with chondrification of the dorsal-fin pterygiophores. Supraneurals 2 and 3 form from separate chondrification centers that subsequently coalesce. In some cyprinids and catostomids, Sn 2 is at first bilaterally paired. This observation demonstrates that supraneurals are not always unpaired, and provides circumstantial evidence that the paired claustra are homologous to Sn l. Claustra in 14 of 15 species examined possessed at least a cartilage rudiment. No evidence was found to support the currently prevalent hypothesis that the claustra form from dissociated parts of the first neural arch.  相似文献   

20.
Heads SW  Leuzinger L 《ZooKeys》2011,(77):17-30
The fossil orthopteran Brauckmannia groeningae Martins-Neto (Orthoptera, Ensifera) from the Early Cretaceous Crato Formation of Brazil, currently misplaced at both the genus and family level, is transferred to the family Schizodactylidae and assigned to the extant genus Schizodactylus Brullé; ergo, Brauckmannia enters synonymy under Schizodactylus and Brauckmanniidae enters synonymy under Schizodactylidae. Schizodactylus groeningae (Martins-Neto), comb. n. agrees in size and general habitus with extant members of the genus, but can be readily separated by the robust, subovoid form of the metatibiae and the distinctive morphology of the lateral metabasitarsal processes. This species represents the first fossil occurrence of Schizodactylidae and the only New World record of this ancient lineage. Phylogenetic relationships of the schizodactylids are reviewed and a sister-group relationship with Grylloidea advocated based on a reappraisal of morphological and molecular evidence.  相似文献   

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