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1.
《Journal of Natural History》2012,46(19-20):1153-1177
Three new Brazilian species of the neotropical land planarian genus Choeradoplana (Platyhelminthes: Tricladida: Continenticola: Geoplaninae) are described, making a total of nine species within the genus. All the new species share unique derived characters typical of the genus. Two of the new species exhibit important features representing morphological variations that were previously unknown for the genus: the dorsal cutaneous longitudinal muscle layer, as well as the ventral one, partially sunken into the parenchyma in one species, and the common ovovitelline duct approaching the copulatory apparatus ventrally in the other. As a consequence of these morphological variations, an emendation of the genus is proposed.  相似文献   

2.
The family Mastacembelidae is currently divided into two subfamilies, the Mastacembelinae and the Afromastacembelinae. Within the African Afromastacembelinae two genera, Caecomastacembelus and Aethiomastacembelus, are recognized. Both the subfamily and the African generic division were critically evaluated mainly through X‐ray analyses and osteological research. There is no supporting evidence for a split into two subfamilies. In addition, the present diagnosis of the African genera proved to be unworkable, and no convincing phylogenetic evidence supporting this classification is available. Therefore, pending new detailed phylogenetic research, the use of a subfamily classification within the family Mastacembelidae is not recommended. Furthermore, Caecomastacembelus and Aethiomastacembelus are placed in synonymy with the genus Mastacembelus.  相似文献   

3.
Five new species of bariliin cyprinid fishes are described from West Africa. Three belong to the genus Leptocypris and two to Raiamas. One species of each genus is from Guinea (Konkoure river) and from Sierra Leone (Taia and Little Scarcies rivers), the other, a Leptocypris, is from Cameroon (Cross River). A taxon of indeterminate generic identity from Guinea is also described. The phylogenetic relationships of the bariliins are hypothesized and in this light their geographical distribution is compared with that of other cladistically analysed African freshwater fish groups. The significance to West African fish distribution of the Togo-Benin (Dahomey) Gap is discussed.  相似文献   

4.
The anatomy and morphology of the pars jugularis skull region in cichlid fishes has been used recently, and for the first time, as a crucial character to establish intrafamilial phylogenies for these African, Malagasian and Neotropical freshwater teleosts. The new phylogeny cuts across relationships postulated in previous schemes, and suggests novel and geographically disjunct intrafamilial groups. It does not, however, seem tenable.

A detailed investigation of the cichlid pars jugularis, involving many more taxa and wider outgroup comparisons than were used to formulate the new classification, is described here. Apart from clarifying certain misconceptions about the anatomy of the pars jugularis in the Cichlidae, this study shows, at least in that family, that the character is valueless as an indicator of higher level intrafamilial relationships, and is of very limited value for establishing phyletic affinities at lower levels.

Other osteological features used in the new classification were also tested on a larger scale. None of these, either, refutes the two other and recent hypotheses-one of intrarelationships amongst Neotropical cichlids and the second for the family as a whole.  相似文献   

5.
《Journal of Natural History》2012,46(10):1487-1512
The genus Platythelphusa is revised and six species are recognized. These species are P. armata A. Milne-Edwards, 1887, P. maculata (Cunnington, 1899), P. conculata Cunnington, 1907, P. tuberculata Capart, 1952, P. polita Capart, 1952 and P. echinata Capart, 1952. A seventh taxon, P. denticulata Capart, 1952 is considered here to be a junior synonym of P. conculata. A diagnosis for each species is provided and most are figured from the type. Keys to the families of African freshwater crabs and to the genus Platythelphusa are also provided.  相似文献   

6.
7.
ABSTRACT

Eulophidae is a hyper-diverse family of chalcidoid wasps with 324 genera, about 5300 described species and probably thousands of others to be described. Until now, the absence of unequivocal morphological apomorphies and the low resolution provided by the handful of Sanger sequenced genes have hampered the reconstruction of phylogenetic relationships within the family. Here, we used ultra-conserved elements and their flanking regions to resolve relationships among 84 species of eulophids included in 63 genera representing all subfamilies and most tribes, plus 15 outgroups. Our analyses recover all traditional Eulophidae subfamilies and tribes with high support and globally agree with the traditional classification of the family. Our results confirm that Eulophinae + Tetrastichinae is the sister group of (Opheliminae + Entiinae) + Entedoninae. At the generic level, our analyses provide high support for intergeneric relationships for which morphology and Sanger markers previously failed to provide resolution. Our results also confirm that Trisecodes does not group with Eulophidae and may not belong to this family; however, its correct classification still awaits a large-scale phylogenomic hypothesis for Chalcidoidea. This work opens new avenues towards a better understanding of the evolutionary history, biogeography and evolution of host–parasitoid associations in this hyper-diverse family of chalcidoid wasps.  相似文献   

8.
9.
Because of their ‘bizarre’ features, some echinoids can be considered laboratories in which to analyse the origin of extreme morphologies. The holasteroid family Urechinidae Duncan, 1889 is such a group. It is composed of 18 previously named living species in three genera: Urechinus A. Agassiz, 1879, Plexechinus A. Agassiz, 1898, and Pilematechinus A. Agassiz, 1904. With Stereopneustes, the most closely related living taxon, and the calymnid-plus-pourtalesiid clade as outgroups, a phylogenetic analysis on 35 binary characters is produced. We focus on two major aspects of morphology: test features (apical system, basicoronals, interambulacrum 5, test shape, ambulacra) and external appendages (pedicellariae, spines, sphaeridia). New data on plate architecture, morphology, and appendages are illustrated, and the position of the fossil, Chelonechinus, is discussed. We show that the Urechinidae is paraphyletic: the genus Plexechinus shares more recent common ancestry with the calymnids and pourtalesiids than with other urechinids. In order to retain the well-circumscribed clade, Pilematechinus A. Agassiz, 1904, the phylogenetic classification also recognizes two additional genera: Cystechinus A. Agassiz, 1879, and Antrechinus new genus. A key to the species is provided. The production of extreme morphologies, such as internal parental care, is explored by mapping test size, the occurrence of fascioles, and periproct position onto the phylogeny. By adding plates early in ontogeny, Pilematechinus develops radically different plate architectures from another genus of large forms, Cystechinus. In contrast, the latter gets large by exaggerating allometric trends seen in other holasteroids. Paedomorphosis and miniaturization have evolved independently in Antrechinus and some Plexechinus, but always by truncation of allometric trajectories.  相似文献   

10.
《Journal of Natural History》2012,46(6):1531-1570
The phylogenetic relationships of the Schizophora with the families of the Aschiza were investigated on the basis of synapomorphies. Depending on the family, the sensory epithelium of the retinae of the compound eyes of flies consists either of populations of two ommatidial elements or of uniform ommatidia: duotype and monotype respectively. Within the Cyclorrhapha, the monotype occurs exclusively in the Schizophora and Syrphoidea (= Syrphidae + Pipunculidae), whereas the duotype occurs in the remaining Aschiza. These two types form a plesio-apomorphous pair: on the basis of character state analysis the duotype was regarded as plesiomorphous and the monotype proved to be a synapomorphy of the Schizophora and Syrphoidea. The retinal pair was accorded a high relevance as an indicator of the phylogenetic relationships in Cyclorrhapha owing to its special morphology and the very low probability of a parallel development of the apomorphous monotype.

In this paper the hypothesis (Hennig, 1976) that the dorsobasal arista on the antennal flagellum in the Schizophora and Syrphoidea is a synapomorphy compared to the original apical arista was confirmed on the basis of literature studies.

The monophyly of these two groups together, and their sister group relationship, were demonstrated in an argumentation scheme. Three alterations of the conventional systematics of the Cyclorrhapha were undertaken: (a) the term ‘Eumuscomorpha’ was introduced to designate a new monophyletic taxon of the Schizophora and Syrphoidea. (b) The remaining groups of the Aschiza were temporarily subsumed in a ‘superfamily Platypezoidea’ owing to their manifestation of complementary symplesiomorphous characteristics. Until its phylogenetic character (monophyly or paraphyly) is unequivocally clarified, it remains an ‘artifical’ entity. (c) The term ‘Aschiza’ is for a taxon of the genealogical system no longer applicable.  相似文献   

11.
12.
The literature on terrestrial and freshwater Tardigrada is relatively limited, being concerned with 617 species world wide. Many of the references are in obscure publications. This paper attempts to bring this information together, tabulating the numbers of tardigrade species recorded from terrestrial and freshwater habitats in various countries and the number of countries from which tardigrades have been recorded. Each record is cross-referenced to the author in the references. It is hoped this paper will serve as a reference point and background for further zoogeographic studies.  相似文献   

13.
《Journal of Natural History》2012,46(16):1977-2032
The morphology of the two species of Australian freshwater assimineids is described in detail. A new genus and species of Assimineinae, Aviassiminea palitans, is named from freshwater springs in north Western Australia and the Northern Territory. Austroassiminea letha Solem et al., 1982 from coastal springs in south Western Australia is also described and the original anatomical account is corrected in several important details. This taxon is shown to be a member of the Omphalotropidinae and is the only other non-marine assimineid known from Australia. All of the described assimineid genus-group taxa are listed in an appendix, with an assessment of their status, and their known diagnostic characters.  相似文献   

14.
15.
Jamaica is the only island of the Greater Antilles where freshwater streams are not populated by representatives of the old lineage of freshwater crabs, the Pseudothelphusidae. Instead, a very diverse fauna of endemic sesarmid crabs inhabits freshwater and terrestrial habitats throughout the island, thereby showing complete independence from the sea. They have been reported thriving in bromeliad leaf axils, rock rubble, empty snail shells, caves and mountain streams. Otherwise, the Sesarmidae are typical inhabitants of soft‐sediment littoral habitats like marshes and mangroves. For many years, crabs from Jamaican mountains streams had been considered to belong to a single species, Sesarma bidentatum Benedict . However, recent morphological and molecular studies have shown that crabs from mountain streams of different regions of the island belong to different species. Consequently, four new crab species have been described over the last 10 years. In this study, we give evidence that freshwater streams in central Jamaica also host two different species of crabs. In streams draining to the north we exclusively found the species S. windsor Türkay and Diesel, , while streams draining to the south were inhabited by a closely related but undescribed species of crab. The southern species is here described as new and is referred to as Sesarma meridies sp. n. Morphological and molecular (12S and 16S mtDNA) evidence is provided that allows these two species of freshwater crabs from central Jamaica to be distinguished. The species richness of Jamaican endemic sesarmids thereby increases to 10, which makes the island unique in terms of its diversity of land‐dwelling crabs.  相似文献   

16.
《Journal of Natural History》2012,46(20):2567-2589
Three species of darwinulid ostracods, belonging to the genus Penthesilenula, are reported from terrestrial and semi-terrestrial habitats in São Paulo State (Brazil). Penthesilenula reidae n. sp. is here described as new to science. It belongs to the africana-group in the genus and was found exclusively in bromeliad pouches. Penthesilenula aotearoa (in the incae-group) was previously known from New Zealand only and is here reported for the first time from South America. The third species, Penthesilenula brasiliensis, is here described from leaf litter in forests, constituting the first darwinulid taxon to be found in fully terrestrial habitats. The morphological diversity within P. brasiliensis s. l. is discussed and various lineages on different continents are retained within this species. The evolutionary significance of the high incidence of teratologies in the Darwinulidae is discussed. A tentative homology for the apical chaetotaxy of A2 between Darwinulidae and Cyprididae is offered.  相似文献   

17.
18.
Previous phylogenetic analysis based on combined mitochondrial and nuclear gene sequences detected paraphyly of the Typhlogammaridae. To test this hypothesis a portion of large subunit (LSU-rDNA) gene sequences were obtained for typhlogammarid species from Caucasus. The Bayesian approach to LSU-rDNA sequences provided evidence for an independent origin of the Dinaric and Caucasus ‘typhlogammarid’ clades. A new family, Zenkevitchiidae fam. nov., is proposed to reconcile the observed phylogeny with the concept of monophyly. Using light microscopy, two mouthpart morphotypes of the Zenkevitchiidae fam. nov. species with quite different setae are identified. Taking into account these two morphotypes, a new classification is proposed – Adaugammarus revazi comb. nov., and Adaugammarus sandroruffoi comb. nov. Additionally, two new stygobiont zenkevitchiid amphipod species – Adaugammarus kasiani sp. nov. and Kruberia relicta sp. nov. – are described from Krubera Cave in Abkhazia. A distribution map and an identification key for the Zenkevitchiidae fam. nov. species of Transcaucasia are provided.

http://zoobank.org/urn:lsid:zoobank.org:pub:90177B0C-BED0-4601-8CFC-3F774B22065C  相似文献   


19.
《Journal of Natural History》2012,46(45-46):2841-2854
A new genus and species of the family Parabathynellidae, Siambathynella laorsriae gen. nov. et sp. nov. is described from Thailand. The new genus displays an exclusive character: a distinctive male thoracopod VIII with a row of denticles on the basipod. The new species also displays a unique combination of morphological characters, including a seven-segmented antennule, seven-segmented antenna, sexual dimorphism on the antennule, exopod of thoracopod I one-segmented, exopod of thoracopod II–VII two-segmented, male thoracopod VIII lacking basipodal seta, female thoracopod VIII with two setae, lacking pleopods, sympod of the uropod with inhomonomous row of spines, and endopod of uropod with a spinous distal process and a large distal spine ornamented with rows of setules. This is the first record of Bathynellacea (family Parabathynellidae) in Thailand, extending the distributional range of this taxon in Asia.  相似文献   

20.
《Journal of Natural History》2012,46(9):1047-1103
A total of 101 verified species and eight ordinal taxa represent the non-marine Crustacea on Antarctica and the islands of the Southern Ocean. The largely terrestrial Isopoda and Amphipoda are confined to some sub-Antarctic and cool temperate islands while the predominantly freshwater Anostraca, Anomopoda, Copepoda (=Calanoida, Cyclopoida, Harpacticoida) and Ostracoda (Podocopida) occur throughout the region. Holocene sea-level rises fragmented freshwater and terrestrial species ranges on New Zealand, Auckland, Campbell, and possibly other South Pacific islands, leaving a legacy of vicariant taxa. Tertiary species probably survived Pleistocene glaciation in aquatic refugia on the New Zealand/South Pacific, Falkland, Crozet and Kerguelen archipelagoes, but there are no valid records of Tertiary Antarctic Crustacea. All 40 Continental and Maritime Antarctic freshwater records can be ascribed to the historic introduction of anthropogenic aliens, Holocene immigration of colonists, returning re-colonists and marine species 'marooned' in epishelf and other coastal lakes.  相似文献   

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