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1.
Four species of lithodid crabs from waters (240–2,005 m) in the Crozet and Kerguelen Islands area were studied. One new species, Neolithodes duhameli, is described. Three other species, N. capensis Stebbing, Paralomis anamerae Macpherson and P. birsteini Macpherson are reported for the first time from these localities. The new species, N. duhameli (620–1,500 m), is the fourth representative of the genus in Subantarctic waters and belongs to the group of species possessing a carapace, chelipeds and walking legs covered with numerous spinules or spiniform granules in addition to spines. However, the new species is distinguishable from others in the genus by the long, strong spines on the carapace and pereiopods. The finding of two species of Paralomis clearly extends their geographic ranges in the Southern Ocean: P. anamerae was previously known only in waters of the Falkland Islands and the circumpolar distribution of P. birsteini is supported. The observation of N. capensis also extends its previously described range from South Africa, in the Cape region, to Subantarctic waters. As a result of this study, 14 species of the family Lithodidae are now known from Antarctic and Subantarctic waters; and most can be considered endemic to these waters.  相似文献   

2.

Plesiochorus Looss, 1901 is a genus of Gorgoderidae infecting the urinary bladders of marine turtles globally. Currently, just two morphologically similar species are recognised, Plesiochorus cymbiformis (Rudolphi, 1819) Looss, 1901 and Plesiochorus elongatus Pigulevsky, 1953, which have been distinguished by molecular data and subtle morphological differences. Here we describe a new species, Plesiochorus irwinorum n. sp., infecting hawksbill turtles (Eretmochelys imbricata (L.)), which is primarily distinguished from the other two species of Plesiochorus on the basis of ITS2, cox1 and 28S sequence data. Morphometric data for specimens examined during this study overlap between P. cymbiformis and P. irwinorum n. sp. for every measured feature, rendering them functionally cryptic. However, principal components analysis clearly distinguishes the two species. Additionally, we report new specimens of P. cymbiformis, and provide new sequence data for specimens from Australian loggerhead (Caretta caretta (L.)) and hawksbill turtles. There is little understanding of the host-specificity or geographical distribution of the three species of Plesiochorus, and it remains possible that some of the previously reported sequences have been attributed to the wrong species.

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3.
Six new species of the genus Phortica are described from Yunnan, Southwest China: P. (Alloparadisa) kaibangya n. sp., P. (Ashima) semiannulata n. sp., P. (Ashima) dianmianensis n. sp., P. (Ashima) idiasta n. sp., P. (Ashima) menglian n. sp. and P. (Ashima) zhangyuanae n. sp. The 22 new DNA sequences of the mitochondrial COI gene with BOLD Process ID and GenBank accession numbers are provided for the six new species and six related known species from southern China: P. (Ashima) glabra, Chen & Toda, 2005 P. (Ashima) nudiarista Cheng & Chen, 2008, P. (Ashima) saltiaristula Chen & Wen, 2005, P. (Ashima) spinosa, Chen & Toda, 2005 P. (Ashima) symmetria Chen & Toda, 2005 and P. (Ashima) yiqini Zhu & Chen, 2017. The pairwise interspecific K-2P COI distances among all Chinese species of the subgenera Alloparadisa and Ashima are summarized. An identification key to males of all Chinese species of the subgenera Alloparadisa and Ashima is provided.  相似文献   

4.
Gall‐forming insects are commonly highly host‐specific, and galling species once thought to be oligo‐ or polyphagous are often found to represent a complex of host‐specific races or cryptic species. A recent DNA barcoding study documented that an unidentified species of the genus Adelges is a gall‐former associated with four spruce species (Picea bicolor, P. koyamai, P. maximowiczii, P. polita) as the primary hosts, with little genetic differentiation among insects on different host species. In this study, we investigated the morphology of this galling adelgid to determine its taxonomic identity. Morphological inspection of insects collected from three of the spruce species confirmed that this adelgid is a single galling species, and is identified as Adelges (Sacchiphantes) kitamiensis, which was previously known only from the secondary host. We described the gallicola adults of this species, as well as the first‐instar exules which are the offspring of gallicolae. Finally, we verified the taxonomic identity of this species and discuss its life cycle and host distribution.  相似文献   

5.
The pigment composition of 18 species (51 strains) of the pennate diatom Pseudo‐nitzschia was examined using HPLC. The carotenoid composition was typical for diatoms, with fucoxanthin (the major xanthophyll), diadinoxanthin, diatoxanthin, and β,β‐carotene. However, a diverse array of chl c pigments was observed in the studied strains. All Pseudo‐nitzschia strains contained chl a and chl c2, traces of Mg‐2,4‐divinyl phaeoporphyrin a5 monomethyl ester (MgDVP), and traces of a chl c2–like pigment originally found in the haptophyte Pavlova gyrans. The distribution of chl c1 and chl c3 was variable among species (present in seven and 14 species, respectively). Based on chl c distribution, three major pigment types were defined: type 1 (chl c1 + c2, four species: P. australis, P. brasiliana, P. multiseries, and P. seriata), type 2 (chl c1 + c2 + c3, three species: P. fraudulenta, P. multistriata, and P. pungens), and type 3 (chl c2 + c3, 11 species: P. arenysensis, P. calliantha, P. cuspidata, P. decipiens, P. delicatissima, P. galaxiae, P. mannii, P. pseudodelicatissima, P. subcurvata, P. cf. subpacifica, and a novel Pseudo‐nitzschia species). Type 1 and 2 species also shared the absence of a particular morphological character, the central nodule in the raphe, with the only exception of P. fraudulenta. The implications of such pigment diversity in chemotaxonomy, HAB monitoring, ecology, and phylogeny of Pseudo‐nitzschia species are discussed.  相似文献   

6.
A list and key to the identification of valid species of tapeworms of the Proteocephalus Weinland, 1858 aggregate sensu de Chambrier et al. (2004), i.e. species of the genus occurring in fresh- and brackish-water fishes in the Palaearctic Region, are provided, with data on their hosts and geographical distribution. Instead of 32 taxa listed by Schmidt (1986) and subsequent authors, only the following 14 species are considered to be valid: P. ambiguus (Dujardin, 1845) (type-species); P. cernuae (Gmelin, 1790); P. filicollis (Rudolphi, 1802); P. fluviatilis Bangham, 1925; P. gobiorum Dogiel & Bychowsky, 1939; P. longicollis (Zeder, 1800); P. macrocephalus (Creplin, 1825); P. midoriensis Shimazu, 1990; P. percae (Müller, 1780); P. plecoglossi Yamaguti, 1934; P. sagittus (Grimm, 1872); P. tetrastomus (Rudolphi, 1810); P. thymalli (Annenkova-Chlopina, 1923); and P. torulosus (Batsch, 1786). An analysis of sequences of the nuclear genes (ITS2 and V4 region of 18S rDNA) revealed the following phylogenetic relationships for these taxa: P. torulosus ((P. midoriensis, P. sagittus) (P. fluviatilis (P. filicollis, P. gobiorum, P. macrocephalus)) (P. cernuae, P. plecoglossi, P. tetrastomus ((P. longicollis, P. percae) (P. ambiguus, P. thymalli)))). P. pronini Rusinek, 2001 from grayling Thymallus arcticus nigrescens is synonymised with P. thymalli. P. esocis La Rue, 1911 is apparently invalid but its conspecificity with either P. percae or P. longicollis could not be confirmed due to the absence of the scolex in the holotype and the unavailability of other material for morphological and molecular studies. P. osculatus (Goeze, 1782) has recently been transferred to Glanitaenia de Chambrier, Mariaux, Vaucher & Zehnder, 2004. The validity of the genus is supported by the position of G. osculata within the Proteocephalidea, based on molecular data, as well as its morphology and nature of the definitive host (the European wels Silurus glanis). P. hemispherous Rahemo & Al-Niaeemi, 2001, described from S. glanis in Iraq, is transferred to Postgangesia Akhmerov, 1960 as Postgangesia hemispherous (Rahemo & Al-Niaeemi, 2001) n. comb.  相似文献   

7.
Bees of genera Xenorhiza and Palaeorhiza of Papua New Guinea collected by Dr Pulawski are reported on. One species of Xenorhiza and 19 species of Palaeorhiza are recognized, including five new species of Palaeorhiza. New taxa are Palaeorhiza (Palaeorhiza) labergei, P. (Anchirhiza) pulawskii, P. (Callorhiza) demeter, P. (Cercorhiza) concordiana and P. (Zarhiopalea) nike.  相似文献   

8.
Squamation and scale morphology were examined in two closely related species, Pleuronichthys cornutus and P. japonicus, in order to establish the unambiguous characters to clearly separate the two species. Scale counts on the lateral body surface were also examined, with new count definitions proposed. Both the longitudinal and vertical scale rows followed essentially regular patterns in P. cornutus, whereas the longitudinal scale rows were occasionally irregular in P. japonicus. Scales were basically fan-shaped and oval in P. cornutus and P. japonicus, respectively, although considerable variation in scale shape was apparent in both species. The blind side scales of P. cornutus had sharp posterior margins, whereas those of P. japonicus had round ones. Scale length (scales on the ocular side, area above the lateral line) in P. japonicus was relatively greater than in P. cornutus, a plot of total length versus scale length separating the species completely. Measurements of many ocular side scales from the area above the lateral line indicated high intraspecific variance in both species, being particularly prominent in P. cornutus. Nevertheless, considerable scale measurement differences were found between the two species in some body areas, supported by principal component analysis. Longitudinal and vertical row scale counts were higher in P. cornutus than in P. japonicus, with the ranges of central longitudinal scales (88–103 vs. 75–86) and scales below the lateral line counts (59–74 vs. 47–57), respectively, not overlapping between the species. The scale count difference could be caused by the difference of the scale size between the two species. The study demonstrated that the two Pleuronichthys species can be readily distinguished on the basis of scale morphology and size, in addition to scale counts.  相似文献   

9.
Wu, Y., Wang, Y., Jiang, K., Chen, X. & Hanken, J. (2009). Homoplastic evolution of external colouration in Asian stout newts (Pachytriton) inferred from molecular phylogeny.—Zoologica Scripta, 39, 9–22. The Asian stout newts of the genus Pachytriton (Salamandridae) inhabit montane streams in south-eastern China. Despite their abundance in the pet trade, the phylogeny and systematics of this genus are poorly understood. Colouration is often used to delimit species under the assumption that consistent chromatic differences characterize independent evolutionary lineages. We present the first phylogenetic study of Pachytriton that incorporates 2.35 kb of mitochondrial DNA (ND2, cytb) and 1.2 kb of nuclear sequence data (RAG-1) along with morphometric characters to infer evolutionary relationships and patterns of colour evolution among the three described species: Pachytriton brevipes, Pachytriton labiatus and Pachytriton archospotus. Our results support the monophyly of Pachytriton and recover P. archospotus as the sister taxon to P. brevipes. Monophyly of P. labiatus is significantly rejected: south-western populations are sister to the group of P. brevipes plus P. archospotus, whereas north-eastern populations nest with P. brevipes. The two geographic units are further separated by multivariate morphological analyses. South-western P. labiatus is the type species; misidentification of north-eastern populations as P. labiatus results from their similar colouration. An unspotted, dark brown dorsum is the likely ancestral state for the genus, whereas black-spotted colouration characterized the common ancestor of P. brevipes, P. archospotus, and north-eastern P. labiatus and was secondarily lost in the latter group. Homoplastic evolution and intraspecific variation render colour pattern in Pachytriton an unreliable character for delimiting species boundaries. North-eastern populations of P. labiatus are declining as the result of human collection and habitat destruction and are in urgent need of conservation protection.  相似文献   

10.
In this study, sequence data from the inert nuclear region ITS1‐5.8S rDNA‐ITS2 and the chloroplast region trnL–F, as well as a few morphological characters, are analysed to the relationships among known annual Poa (bluegrasses). It is shown that all taxa from the Poa annua aggregate distinguished by lemma characters and growth form have identical ITS and trnL–trnF sequences, all ITS sequences of this aggregate are the same as thethose of P. supina, and all trnL–trnF sequences are homologous with those of P. infirma. Furthermore, no differences were found between unusual morphotypes of P. supina with short spinules on their panicle branches and typical plants, but Siberian samples were found to have a slightly differentiated trnL–trnF region. These results suggest a hybrid origin of the Asian annual bluegrasses. Their maternal genome is close to that of P. sect. Homalopoa, but their ITS sequences are different. Some ITS sequences from annual Asian bluegrasses are resolved among representatives of P. sect. Stenopoa while for other (morphologically closely similar) species they fall in a clade with representatives of P. sect. Malacanthae. The latter group is distant from P. sect. Ochlopoa and is better treated as a separate section, viz P. sect. Acroleucae. The American annual bluegrasses are heterogeneous and also rather distant from P. sect. Ochlopoa. Poa chapmaniana, a species with cleistogamic flowers, is nested among the basal Subantarctic sections, far away from the taxa with which it has previously been considered related. It is indeed closer to P. sect. Ochlopoa than to other annual American bluegrasses. Thus, the studied annual species in fact belong to four independent evolutionary lines (or six including the separate genus Eremopoa and the Turkish Poa jubata), one of which, Acroleucae, has gone through three reticulation events. As in previous studies, our analysis did not support the generic status of P. sect. Ochlopoa.  相似文献   

11.
Abstract

Data are presented on the life cycles of eight species of Neolimnia, an endemic New Zealand genus of snail-killing flies. Habitats, geographical distributions, biological features of adults and immature stages, including adult and larval behaviour and feeding habits, and phenology are discussed. Larvae of subgenus Pseudolimnia live in aquatic environments; those of N. (P.) repo, N. (P.) sigma, and N. (P.) ura prey on aquatic pulmonate snails, but those of N. (P.) tranquilla prey on aquatic prosobranch snails. Larvae of Neolimnia (Neolimnia) castanea, N. (N.) irrorata, N. (N.) obscura, and N. (N.) striata live in terrestrial environments, and apparently prey overtly on terrestrial snails in nature, but will also attack aquatic snails in laboratory rearings.  相似文献   

12.
Four species of the genus Panonychus are identified in Korea including two previously known species P. citri (McGregor) and P. ulmi (Koch) and two newly identified species P. mori Yokoyama and P. caglei Mellot. Morphological diagnostics were observed among the four species in the color of dorsal tubercles and in the shape of male aedeagus. The dorsal tubercles of P. citri, P. ulmi, P. mori and P. caglei are red, white, whitish red and light red, respectively. The aedeagi of male adults are diagnostic in sigmoid‐shaped at the distal end and its shape and length was different among four species. Molecular comparison of the internal transcribed spacer 2 (ITS2) sequence of nuclear DNA and cytochrome‐c oxidase subunit I (COI) nucleotide sequence of mitochondrial DNA among the four species showed divergences 8–12% and 9–12%, respectively. Molecular analysis of the ITS2 and COI sequences revealed their divergences were slightly different among four species. In addition, species‐specific primer sets were designed at the base on ITS2 sequences to precisely diagnose these four species at the molecular level.  相似文献   

13.
The Puma lineage is a monophyletic group that includes three living species: Puma concolor, Herpailurus yagouaroundi, and Acinonyx jubatus. It has been analysed from ecological and taxonomic perspectives, but their cranial ontogeny has been poorly studied. In this study, we assessed the cranial shape and size variation through three‐dimensional geometric morphometric techniques, and explored the acquisition of definitive shape and size in relation to key life‐history events. Each species occupied different locations in the shape morphospace: A. jubatus and P. concolor showed shorter and wider skulls, with more expanded zygomatic arches, than H. yagouaroundi, which presented the most divergent pattern of change. Ontogeny was more similar between P. concolor and A. jubatus than between the closely related P. concolor and H. yagouaroundi. The evolution of ontogenetic change in the lineage seems to be more influenced by size. Changes detected between juvenile and adult skulls enhanced predatory skills, coincident with the change from a diet of milk to a carnivorous diet. Change patterns suggest that the skull is not morphologically conservative in the lineage, in contrast with other carnivores such as canids and hyaenids. The enlargement of the rostrum observed in some canids and the reinforcement of the bite mechanism of hyaenids were not detected in this group. © 2013 The Linnean Society of London  相似文献   

14.
15.
Due to accidental introductions, the distribution of the east Asian topmouth gudgeon, Pseudorasbora parva, has rapidly expanded over recent years, thereby threatening the endangered Japanese species, P. pumila pumila. Sixteen microsatellite loci were isolated and characterized for P. parva, 14 being highly polymorphic (mean HE = 0.58, mean number of alleles = 4.4). Successful characterization of 10 of these loci was also achieved for P. pumila pumila. These markers should be useful in future investigation of colonization of P. parva and the development of conservation strategies for P. pumila pumila.  相似文献   

16.
Hybridization and introgression can play an important role in speciation. Here, we examine their roles in the origin and evolution of Picea purpurea, a diploid spruce species occurring on the Qinghai–Tibet Plateau (QTP). Phylogenetic relationships and ecological differences between this species and its relatives, P. schrenkiana, Plikiangensis and Pwilsonii, are unclear. To clarify them, we surveyed sequence variation within and between them for 11 nuclear loci, three chloroplast (cp) and two mitochondrial (mt) DNA fragments, and examined their ecological requirements using ecological niche modelling. Initial analyses based on 11 nuclear loci rejected a close relationship between P. schrenkiana and Ppurpurea. BP&P tests and ecological niche modelling indicated substantial divergence between the remaining three species and supported the species status of P. purpurea, which contained many private alleles as expected for a well‐established species. Sequence variation for cpDNA and mtDNA suggested a close relationship between Ppurpurea and Pwilsonii, while variation at the nuclear se1364 gene suggested Ppurpurea was more closely related to Plikiangensis. Analyses of genetic divergence, Bayesian clustering and model comparison using approximate Bayesian computation (ABC) of nuclear (nr) DNA variation all supported the hypothesis that Ppurpurea originated by homoploid hybrid speciation from Pwilsonii and Plikiangensis. The ABC analysis dated the origin of Ppurpurea at the Pleistocene, and the estimated hybrid parameter indicated that 69% of its nuclear composition was contributed by Plikiangensis and 31% by P. wilsonii. Our results further suggested that during or immediately following its formation, P. purpurea was subject to organelle DNA introgression from Pwilsonii such that it came to possess both mtDNA and cpDNA of Pwilsonii. The estimated parameters indicated that following its origin, Ppurpurea underwent an expansion during/after the largest Pleistocene glaciation recorded for the QTP.  相似文献   

17.
This study reports about the spermatozoal ultrastructure of three species of astacid crayfish, i.e., the stone crayfish Austropotamobius torrentium, signal crayfish Pacifastacus leniusculus, and noble crayfish Astacus astacus. The acrosome is a cup shaped and electron‐dense structure at the anterior of the spermatozoon and comprises three layers of differing electron densities filled with parallel filaments that extend from the base to the apical zone. The acrosome was significantly longer in A. astacus than in P. leniusculus and the shortest acrosome belongs to A. torrentium. The width of the acrosome was significantly narrower in A. torrentium than in P. leniusculus and the widest acrosome belongs to A. astacus. The L:W ratio was significantly greater in A. torrentium than in P. leniusculus and the lowest ratio belongs to A. astacus. Radial arms are visible on each side of the acrosome or nucleus in sagittal view and wrap around the spermatozoon. Each radial arm comprises a parallel bundle of microtubules arranged along the long axis within a sheath. The nucleus, with decondensed material, is located in the posterior of the cell. All parts of the spermatozoon are tightly enclosed within an extracellular capsule. Despite a well‐conserved general structure and similarity of pattern among these spermatozoa, differences in the dimensions of the acrosome within the studied species may be useful to help distinguish the different crayfish species. J. Morphol., 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

18.
Three Primula species, Primula vulgaris, P. veris and P. elatior, have been objects of fascination for gardeners and botanists over several centuries. The species are able to hybridise, and where they co‐occur, hybrids are commonly found. In Denmark, Møns Klint on the island of Møn and Købelev Skov on Lolland are examples of localities where all three species occur and where the hybrids P. × digenea, the hybrid between P. vulgaris and P. elatior, and P. × polyantha, the hybrid between P. veris and P. vulgaris, can also be found. To investigate relationships between the species and their hybrids, we sampled 168 specimens from 10 geographical locations and subjected them to genetic analysis. The samples were also identified based on morphological traits: primarily inflorescense structure, the size, shape, colour and markings of corolla and leaf basis, leaf blade texture and hairiness. After identifying species‐specific SNPs in the Internal Transcribed Spacer sequence, these were used to resolve species and hybrid boundaries and status through a cleaved amplified polymorphic sequence assay. Polymorphisms in the chloroplast trnL sequence were used as a high‐throughput marker and used to determine the maternal parent of hybrids. Ten simple sequence repeat markers were applied to obtain further insight into the genetic makeup of the accessions using structure and Introgress, providing information of genetic variability within and between populations. Our results indicated that backcrossing of P. × digenea hybrids with parental species has occurred, and that many of the P. × digenea sampled were later‐generation hybrids rather than F1s. Analyses of P. × polyantha specimens show mostly the expected pattern for primary hybrids but indications of P. veris ancestry of a P. vulgaris plant was discovered. Our results further indicate that some of the specimens initially identified as P. elatior include P. vulgaris among their progenitors and thus challenge currently accepted species boundaries.  相似文献   

19.
20.
Freshwater fish evolution has been shaped by changes in the earth's surface involving changes in the courses of rivers and fluctuations in sea level. The main objective of this study is to improve our knowledge of the evolution of loricariids, a numerous and adaptive group of freshwater catfish species, and the role of geological changes in their evolution. We use a number of different phylogenetic methods to test the relationships among 52 representative taxa within the Neoplecostominae using 4676 bps of mitochondrial and nuclear DNA. Our analysis revealed that the subfamily Neoplecostominae is monophyletic, including Pseudotocinclus, with three lineages recognized. The first lineage is composed of part of Pareiorhina rudolphi, P. cf. rudolphi, and Pseudotocinclus; the second is composed of Isbrueckerichthys, Pareiorhaphis, Kronichthys, and the species Neoplecostomus ribeirensis; and the third is composed of Pareiorhina carrancas, P. cf. carrancas, Pareiorhina sp. 1, a new genus, and all the species of the genus Neoplecostomus, except N. ribeirensis. The relaxed molecular clock calibration provides a temporal framework for the evolution of the group, which we use for a likelihood‐based historical biogeographic analysis to test relevant hypotheses on the formation of southeast Brazil. We hypothesize that headwater capture events and marine regressions have shaped the patterns of distribution within the subfamily Neoplecostominae throughout the distinct basins of southeast Brazil.  相似文献   

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