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In conservation biology there is a basic need to determine habitat suitability and availability. Astroblepus ubidiai (Siluriforms), the only native fish in the highlands of Imbabura province in the Ecuadorian Andes, was abundant in the past in the Imbakucha watershed and adjacent drainages, but currently it is restricted to a few isolated refuges. Conservation actions are needed if this unique fish is to persist. A Habitat Suitability Index (HSI) for the species has been developed in order to aid management decisions. In this HSI model biomass density (B) was selected as a better indicator of habitat quality than either abundance or density. A population well-being index (PI) was constructed with the combination of B and an indicator of fish health (proportion of fish in the population with parasites and deformities). Based in other models of benthic fish the habitat variables current velocity, flow, depth, width, cover, invertebrate composition, vegetation type, terrestrial vegetation, land use, substrate, temperature, pH, TDS, oxygen, altitude, and slope were included in the analysis. An anthropogenic perturbation index (H) and a fragment isolation index (FII) were developed and included as habitat variables as well. The HSI model was applied to refuges and a sample of 15 aquatic bodies without fish populations within the study region. From the sampled sites without A. ubidiai 26.6% presented low quality, and the remaining 73.3% had medium quality according to the HSI estimated. Good quality habitat for dispersal, escape or translocations is rare in the region. The low HSIs estimated in some of the refuges suggests that current populations are not settled in the most favorable habitat but in the habitat least favorable to the agents of decline.  相似文献   

3.
The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.  相似文献   

4.
Geranium sect.Gracilia (Geraniaceae) comprises nine species in the Andes of Venezuela and Colombia.Geranium lindenianum andG. gracilipes are synonymized withG. holosericeum. The identity ofG. multiceps is clarified. Its differences from the two Colombian species,G. santanderiense andG. lainzii, are discussed.Geranium lignosum, G. sebosum, G. stoloniferum, G. subnudicaule, andG., velutinum are now considered to be members of sect.Gracilia. The identity ofG. pilgerianum could not be clarified because the type was destroyed and other collections have not been found. Micromorphological leaf and seed characters are discussed. Six lectotypes and one neotype are designated.
Resumen  Se revisaGeranium sect.Gracilia (Geraniaceae), un grupo formado por nueve especies distribuidas por los Andes de Venezuela y Colombia. Se sinonimizanG. lindenianum y G. gracilipes aG. holosericeum. Se aclara la identidad deG. multiceps y se establecen sus diferencias conG. santanderiense y conG. lainzii, ambas esencialmente colombianas. Se aceptan en esta secciónG. lignosum, G. stoloniferum yG. sebosum, propuestos tras la descripción de la sect.Gracilia, yG. subnudicaule yG. velutinum, ya tratados por otros autores en como pertenecientes a este grupo. Por el contrario, la identidad deG. pilgerianum no ha podido ser aclarada tras la destrucción del tipo y ante la falta de otros materiales de la especie. Se estudian diversos caractere micromorfológicos, especialmente algunos referibles a la anatomía foliar y la de la semilla. Se designan seis lectótipos y un neótipo.
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5.
During satellite-tracking investigations of 140 white storks (Ciconia ciconia), one individual, the long-term world record holder among birds, was followed along 12 migratory journeys over a period of 10 years. This long-term study confirms what previous several-year tracking studies of white storks had indicated: there can be great variability from year to year in the choice of winter quarters as well as in the routes and times of migration, intermediate destinations and stop-over periods, but constancy of winter quarters and migration routes is also possible. The variability may well be caused by external factors, of which food supply is probably predominant.Communicated by F. Bairlein  相似文献   

6.
A new sanguinicolid trematode, Cardicola aurata sp. n., is described from gilthead seabream Sparus aurata L., from off the Spanish Mediterranean coast. The morphology of C. aurata sp. n. generally agrees with the diagnosis of the genus, however, in contrast to all other reported Cardicola spp. the male pore is located sub-medially at the posterior end of the body instead of sinistrally before the posterior end of the body. Based on a comparison of the morphology as well as partial 28S and ITS2 rDNA sequence data from the present species with that from closely related species, it was decided to emend the diagnosis of Cardicola rather than create a new genus, as the aberrant position of the male pore is likely to be an autapomorphy. The phylogenetic analyses revealed a close relationship between Cardicola and Paradeontacylix, two genera with considerable morphological differences; C. aurata sp. n. occupies a position intermediate to these genera. Thus, a morphological comparison of Cardicola, Paradeontacylix and Braya, a genus which is morphologically similar to Cardicola but clusters basal to the Cardicola/Paradeontacylix clade, was conducted. The results of this comparison showed that despite large differences with regard to body shape, the organisation of the internal organs is very similar in species of Cardicola and Paradeontacylix. The synopsis of morphological data and molecular phylogeny allows for interpretations regarding the importance of different morphological features for the phylogenetic inference of the Sanguinicolidae.  相似文献   

7.
This contribution provides an insight into Atheriniformes systematics based on four mitochondrial regions: 12S rRNA, cytb, COI and control region (2794bp in total). In the Atherinopsoidei (New World silversides), comparisons among five species of Odontesthes, O. argentinensis, O. bonariensis, O. smitti, O. hatcheri and O. incisa revealed a putative marine-freshwater pairing pattern of Odontesthes species, possibly driven by sea level fluctuations of South American waters. This study represents the first data on molecular phylogeny of Odontesthes species that can be of usefulness to biodiversity conservation policies. In the Atherinoidei (Old World silversides), Atherina boyeri was corroborated as a species complex constituted by a marine form, a marine with dark spots form and a brackish form. Concretely, Odontesthes and Atherina may represent geographically replicated models to study genetic adaptation and speciation of marine species to brackish and freshwater habitats. In addition, phylogenetic analyses supported Odontesthes and Atherina as monophyletic taxa and their separation into two differentiated suborders Atherinopsoidei and Atherinoidei, respectively.  相似文献   

8.
GlyptothoraxBlyth (1860) is the most species-diverse and widely-distributed genus in the Sisoridae, but few studies have examined monophyly of the genus and phylogenetic relations within it. We used the nuclear RAG2 gene and mitochondrial COI and Cyt b genes from 50 of the approximately 70 species to examine monophyly of Glyptothorax and phylogenetic relationships within the genus. Molecular phylogenetic trees were constructed using maximum parsimony, maximum likelihood and Bayesian inference methods. All methods strongly supported monophyly of Glyptothorax, with Bagarius as its sister group. Both analyses of two- and three-gene datasets recovered nine major subclades of Glyptothorax, but some internal nodes remained poorly resolved. The phylogenetic relationships within the genus and existing taxonomic problems are discussed.  相似文献   

9.
广义无心菜属(Arenaria L.s.l.)是石竹科(Caryophyllaceae)中分类较为困难的大属之一,基于分子系统学研究结果该属目前已被拆分为多属.基于形态学证据,桃色无心菜(Arenaria melandryoides Edgew.)被置于无心菜属齿瓣亚属[subg.Odontostemma(G.Don)...  相似文献   

10.
Pseudobagrus brachyrhabdion sp. nov., from the Yuan Jiang and Xiang Jiang of the middle Yangtze River drainage in Hunan and Guizhou Provinces, South China, is described herein. It is distinguished from all other Pseudobagrus species with a truncate or slightly emarginated caudal fin by an unique combination of the following characters: supraoccipital plate and nuchal plate broadly interspaced and covered with skin; nasal barbels only at most reaching anterior margin of eye; maxillary barbels reaching slightly beyond posterior margin of eye; outer mandibular barbels extending to posterior margin of eye; dorsal fin with a somewhat convex distal margin, origin nearer to pectoral-fin insertion than to pelvic-fin insertion; dorsal-fin spine shorter than pectoral spine, with a somewhat serrated posterior margin; pectoral-fin spine with a smooth anterior margin; anal fin with 20–23 rays, base length 23.8–32.0% of standard length, posterior end of anal-fin base anterior to posterior end of adipose fin base; no longitudinal black band extending along flank; eyes large, diameter 16.3–23.7% of head length; and number of vertebrae 5 + 43–46.  相似文献   

11.
Synopsis Pristis microdon, P. zijsron, P. clavata and Anoxypristis cuspidata are distributed throughout the Queensland section of the Gulf of Carpentaria, Australia. In a survey of the four species, Anoxypristis cuspidata was the most abundant and was recorded in both the inshore and offshore set net fisheries. The size distribution and catch locations of A. cuspidata suggest that the inshore area to a depth of 10 m may be the preferred habitat for juveniles of this species, while adults primarily occur offshore. Pristis microdon, P. zijsron and P. clavata were recorded only in the inshore fishery with catches dominated by immature animals. Pristis microdon was caught in the inshore fishery late in the monsoonal wet season (February to April) and inhabited both freshwater and estuarine environments. Pristis zijsron occurred only on the sand and mud flats outside river mouths whilst P. clavata inhabited both the sand and mud flats and upstream estuarine habitats. Observations on reproductive staging and the capture of neonate specimens suggest that in all four pristids, pupping occurred through the wet season until the beginning of the dry season in May. A seasonal set net closure for the barramundi, Lates calcarifer and shark fisheries, which has been in place since 1980 in Queensland Gulf waters, therefore offers a measure of protection to breeding female sawfish and their offspring.  相似文献   

12.
Spawning aggregations in coral-reef fishes have been hypothesized to confer any one of several mutually non-exclusive benefits, largely expected to serve the interests of both sexes simultaneously. Here we provide indication that in the brown surgeonfish, Acanthurus nigrofuscus, spawning aggregations may confer a sex-specific benefit. Following tagged individuals en-route to their daily spawning-aggregation site we found that while migrating groups (≤20 fish) consist of both males and females, females tend to occupy the lead position more often than expected by chance. In addition, we found evidence that female A. nigrofuscus divide their daily egg-stock among several spawning bouts within the aggregations. We propose that female leadership en-route to spawning aggregations, together with the potential benefits of multiple female mating, are consistent with a sex-specific benefit to spawning aggregations.  相似文献   

13.
Phylogenetic relationships of the Malagasy and Australasian rainbowfishes are investigated using 4394 characters derived from five mitochondrial genes (12S, 16S, tRNA-Valine, ND5, and COI), three nuclear genes (28S, histone H3, and TMO-4c4), and 102 morphological transformations. This study represents the first phylogenetic analysis of the endemic Malagasy family Bedotiidae and includes a nearly complete taxonomic review of all nominal species, as well as numerous undescribed species. Simultaneous analysis of the molecular and morphological datasets results in two equally most parsimonious trees. Results indicate that Bedotiidae (Bedotia+Rheocles) and Bedotia are monophyletic, whereas Rheocles is paraphyletic with the inclusion of two recently described species from northeastern Madagascar, R. vatosoa, and R. derhami. Rheocles vatosoa and R. derhami are sister taxa, and this clade is recovered as the sister group to Bedotia. The remaining species of Rheocles are not sexually dimorphic and comprise a clade that is recovered as the sister group to Bedotia+(R. derhami+R. vatosoa), all of which are sexually dichromatic, and sexually dimorphic for pigmentation and fin development. Three geographically distinct clades are recovered within Bedotia, one comprising species with distributions ranging from mid- to southeastern Madagascar, another including species restricted to eastern drainages north of the Masoala Peninsula, and a third comprising taxa with distributions extending from the Masoala Peninsula south to the Ivoloina River. The Australian/New Guinean melanotaeniids are monophyletic and are recovered as the sister group to Bedotiidae. The Australasian Telmatherinidae and Pseudomugilidae comprise a clade that is recovered as the sister group to the Melanotaeniidae-Bedotiidae clade. This sister-group relationship between Malagasy bedotiids and a clade restricted to Australia-New Guinea, and the absence of a close relationship between bedotiids and African or Mascarene atheriniforms, is congruent with the break-up of Gondwana, not a scenario reliant on Cenozoic trans-oceanic dispersal. Finally, results of the phylogenetic analysis indicate that Atheriniformes is polyphyletic and further corroborate recent morphological hypotheses, which have recovered Bedotiidae in a derived position within Atherinoidei.  相似文献   

14.
Yoshitaka Ono 《Mycoscience》2006,47(3):145-151
Ochropsora ariae was found to host-alternate between Anemone pseudo-altaica and Aruncus dioicus var. tenuifolius and Ochropsora nambuana between Anemone flaccida and Elaeagnus multiflora var. hortensis in Japan. Both species produced a sessile, thin-walled, cylindrical probasidium (teliospore), which turned into a four-celled metabasidium by continuous apical elongation of the probasidium. Several probasidia of O. nambuana were produced from a basal basidiogenous cell in a sorus hymenium. Life cycle and probasidium/metabasidium morphology showed the taxonomic identity of Ceraceopsora elaeagni with O. nambuana. Developmental morphology of the basidium found in the two Ochropsora species raised a question against the taxonomic separation of Ochropsora and Aplopsora.  相似文献   

15.
Body size and colouration are two characters commonly used in the taxonomy of many animal taxa. However, they are seldom used by earthworm taxonomists because they are subject to environmental influences and tend to vary intraspecifically. In the present study, DNA sequences of the mitochondrial COI gene are used to evaluate whether specimens of the megascolecid earthworm Amynthas wulinensis Tsai, Shen & Tsai, 2001 that differ in body size and/or colouration belong to different genetic lineages. Phylogenetic analyses and morphological comparisons indicate that A. wulinensis in the previous broad sense is a species complex composed of three species differing in body size, colouration, and genital markings. Consequently, two new species, Amynthas lini and Amynthas meishanensis, are described. Taxonomic affinities of the A. wulinensis species complex are discussed, as is the feasibility of using body size and colouration in earthworm taxonomy.  相似文献   

16.
Sinocyclocheilus donglanensis, a new cyprinid species from a subterranean river in Donglan County in the Guangxi Zhuang Autonomous Region of southern China, is described. It is distinguished from all congeners by the following combination of characteristics: a completely scaled body with well-developed eyes; a curved lateral line possessing 57–64 scales; pectoral fin not reaching pelvic fin origin and last unbranched ray of the dorsal fin clearly serrated along its posterior edge; 8–9 predorsal vertebrae; 8–9 gill rakers; joints of dentary-angulars not close to each other at the isthmus; and a slightly inferior mouth with the upper jaw (6.2–7.4% in standard length: SL) protruding slightly beyond the lower one (5.7–6.7% SL). Sinocyclocheilus donglanensis is sympatric with the peculiarly shaped, hunchbacked S. altishoulderus.  相似文献   

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发现近来根据云南西北部丽江标本描述的毛茛科短尾翠雀花(Delphinium brachyurum W. T. Wang)与此前根据该地标本描述的丽江翠雀花(D. likiangense Franch.)属于同一种植物,故将前者处理为后者的异名。  相似文献   

19.
The generic names of the brown algaeMyagropsis, Cystoseira andCystophyllum have been used in Japan, Korea and China for a small group of seaweeds whose limits have not been clearly understood. Studies on the development of the eggs and subsequent germlings show that substantial differences occur betweenCystoseira andMyagropsis. Myagropsis Kützing is distinguished fromCystoseira C. Agardh by the following characteristics: (1) the tongue cell is undivided during development of the conceptacle; (2) paraphyses are projected from the conceptacle ostiole and become entangled; (3) during development, oospore germlings are mixed among paraphyses projecting from the ostiole; (4) oospores are large, with eight nuclei at maturity; (5) thirty-two primary rhizoids are produced on the germlings; and (6) the thallus is bilateral in organization. The shape and size of vesicles, their formation, and the presence of cryptostomata have been used as specific characters, but their use cannot be continued. It is concluded that the genusMyagropsis is monotypic, with a single species,M. myagroides (Turner) Fensholt. The status of this species is also discussed.  相似文献   

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