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1.
The gymnophthalmid lizard R iolama inopinata sp. nov. is described from the summit of Murisipán‐tepui, Bolívar State, Venezuela. The new species is characterized by its small size, slender body, short neck, chestnut brown dorsum with two conspicuous orange‐brown dorsolateral stripes, 30 or 31 mid‐dorsal scales, and 18 or 19 ventral scales in transverse rows, 28 scales around midbody, seven supralabials, five or six infralabials, subdigital lamellae divided in small granular scales, ten or 11 small femoral pores in males, dorsal surface of tongue covered with oblique chevron‐shaped plicae interrupted by a small midsection of imbricate scale‐like papillae, and a small weakly bilobed hemipenis having the sulcus spermaticus flanked by an extensive nude area on each side, and the asulcate and lateral faces of the organ with short series of small roughly equidistant, feebly developed flounces, each bearing a single medial hook‐shaped spine. Molecular phylogenetic analyses based on one nuclear and two mitochondrial DNA genes confirm the allocation of the new species to the genus Riolama, but do not support the assignation of Riolama to the subfamily Cercosaurinae as previously suggested based on overall morphological similarities, nor to any other known subfamily of the Gymnophthalmidae. Therefore, a new subfamily, the Riolaminae, is proposed to accommodate the genus. © 2015 The Linnean Society of London  相似文献   

2.
Forest or mouse shrews (Myosorex) represent a small but important radiation of African shrews generally adapted to montane and/or temperate conditions. The status of populations from Zimbabwe, Mozambique, and the north of South Africa has long been unclear because of the variability of traits that have traditionally been ‘diagnostic’ for the currently recognized South African taxa. We report molecular (mitochondrial DNA and nuclear DNA), craniometric, and morphological data from newly collected series of Myosorex from Zimbabwe (East Highlands), Mozambique (Mount Gorogonsa, Gorongosa National Park), and the Limpopo Province of South Africa (Soutpansberg Range) in the context of the available museum collections from southern and eastern Africa and published DNA sequences. Molecular data demonstrate close genetic similarity between populations from Mozambique and Zimbabwe, and this well‐supported clade (herein described as a new species, M yosorex meesteri sp. nov. ) is the sister group of all South African taxa, except for Myosorex longicaudatus Meester & Dippenaar, 1978. Populations of Myosorex in Limpopo Province (herein tentatively assigned to Myosorex cf. tenuis) are cladistically distinct from both Myosorex varius (Smuts, 1832) and Myosorex cafer (Sundevall, 1846), and diverged from M. varius at approximately the same time (2.7 Mya) as M. cafer and Myosorex sclateri Thomas & Schwann, 1905 diverged (2.4 Mya). Morphometric data are mostly discordant with the molecular data. For example, clearly distinct molecular clades overlap considerably in craniometric variables. On the other hand, extreme size differentiation occurs between genetically closely related populations in the Soutpansberg Range, which coincides with the bissection of the mountain range by the dry Sand River Valley, indicating the potential for strong intraspecific phenotypic divergence in these shrews. © 2013 The Linnean Society of London  相似文献   

3.
4.
We present five case studies among articulate (rhynchonelliform) brachiopods, i.e. of Rhynchonellida, Cancellothyridoidea, Terebratuloidea, Dyscolioidea, Laqueoidea, and various terebratulids with modified long‐loops, in an attempt to illustrate and better understand congruence and conflict between morpho‐classification and rDNA‐based molecular clade structure, having been prompted to address these issues by difficulties encountered when describing the newly collected brachiopod, E biscothyris bellonensis gen. et sp. nov. The five studies reveal dramatic conflict in the Rhynchonellida and Terebratuloidea/Dyscolioidea, good congruence in the Cancellothyridoidea and Laqueoidea, and fair congruence (albeit with weak phylogenetic signal) in the long‐looped terebratulids. We suggest that the leading cause of the observed conflict lies in the use of inadequately specific morphological characters and morpho‐classification. Phylogenetic systematic (cladistic) analyses of Rhynchonellida also conflict markedly with the rDNA gene tree, leading us to recognize that such analyses are not only conceptually circular (using morphological characters to assess a morphological classification) but also to propose that they are biased by the act of classification that necessarily precedes the identification of putatively homologous characters; when the prior classification does not reflect evolutionary history, phylogenetic analysis will do likewise. In addition, we propose that the brachiopod community has overlooked the significance of two sources of morphological homoplasy affecting brachiopod systematics: (1) the loss of co‐adapted genomic complexes caused by mass extinctions at the end of the Permian; and (2) the pervasive consequences of developmental integration and constraint resulting from the integrated roles of the outer mantle epithelium in shell deposition and growth that underly the determination of form and the shell‐based classification. © 2015 The Linnean Society of London  相似文献   

5.
6.
We describe a new species of Alopoglossus from the Pacific slopes of the Andes in northern Ecuador based on morphological and molecular evidence. The new species differs most significantly from all other congeners in having a double longitudinal row of widened gular scales, lanceolate dorsal scales in transverse rows, 29–32 dorsal scales in a transverse row at midbody, and 4 longitudinal rows of ventrals at midbody. It is most similar in morphology to A. festae, the only species of Alopoglossus currently recognized in western Ecuador. We analyze the phylogenetic relationships among species of Alopoglossus based on the mitochondrial gene ND4. Cis-Andean [east of the Andes] and Trans-Andean [west of the Andes] species are nested in two separate clades, suggesting that the uplift of these mountains had an important effect in the diversification of Alopoglossus. In addition, we present an updated key to the species of Alopoglossus.  相似文献   

7.
A new species Lepidocephalichthys manipurensis , is described, confined to the Chandel district of Manipur near the adjoining borderland areas of Manipur, India and Burma (Myanmar). It is distinguished by the following combination of characters: a sharp small black dot just above the upper base of the caudal fin; 8–9 dorsal short dark ashy brown bars from occiput to the base of the caudal fin; absence of scales on the vertex of head; caudal fin fork, pectoral, ventral and anal fins are non-immaculate; least depth of caudal peduncle 50·00–60·24% (mean 54·09) of its length and 7·69–8·11% L , S (mean 8·22); caudal fin with 4–5 W-shaped bands: a single dark black stripe from tip of snout to eye; 8–11 spots on the mid lateral line; and 30–31 vertebrae. A key to the identification of lepidocephalid loaches of Manipur is provided.  相似文献   

8.
Monoclonal strains of Chaetoceros species were collected from Chinese warm waters. Vegetative cells and resting spores were examined using light microscopy as well as scanning and transmission electron microscopy. Combined morphological and DNA sequence data from the hypervariable D1–D3 region of the nuclear ribosomal large subunit showed the presence of two new species within the section Compressa, herein described as Chaetoceros bifurcatus sp. nov. and C. millipedarius sp. nov. Both species possessed features typical of the section Compressa, but C. bifurcatus was characterized by the heavy intercalary setae fusing and extending together for a distance before diverging. The heavy setae were not visually contorted, lacking poroids and spines, in contrast with how the section Compressa has been defined. Chaetoceros millipedarius was characterized by a horizontal stagger of ordinary intercalary setae when the chain was seen in broad girdle view, making the chain look like a millipede. The two new species were supported by molecular phylogenetic analyses with C. bifurcatus sister to C. contortus var. ornatus, while C. millipedarius was sister to C. contortus var. contortus. Based on the morphological features exhibited in C. bifurcatus, the diagnosis of the section Compressa was emended to exclude “contorted” heavy setae and compressed valve faces.  相似文献   

9.
Developmental plasticity is often correlated with diversity and has been proposed as a facilitator of phenotypic novelty. Yet how a dimorphism arises or how additional morphs are added is not understood, and few systems provide experimental insight into the evolution of polyphenisms. Because plasticity correlates with structural diversity in Pristionchus nematodes, studies in this group can test the role of plasticity in facilitating novelty. Here, we describe three new species, Pristionchus fukushimae sp. nov. , Pristionchus hoplostomus sp. nov. , and the hermaphroditic Pristionchus triformis sp. nov. , which are characterized by a novel polymorphism in their mouthparts. In addition to showing the canonical mouth dimorphism of diplogastrid nematodes, comprising a stenostomatous (‘narrow‐mouthed’) and a eurystomatous (‘wide‐mouthed’) form, the new species exhibit forms with six, 12, or intermediate numbers of cheilostomatal plates. Correlated with this polymorphism is another trait that varies among species: whereas divisions between plates are complete in P. triformis sp. nov. , which is biased towards a novel ‘megastomatous’ form comprising 12 complete plates, the homologous divisions in the other new species are partial and of variable length. In a reconstruction of character evolution, a phylogeny inferred from 26 ribosomal protein genes and a partial small subunit rRNA gene supported the megastomatous form of P. triformis sp. nov. as the derived end of a series of split‐plate forms. Although split‐plate forms were normally only observed in eurystomatous nematodes, a single 12‐plated stenostomatous individual of P. hoplostomus sp. nov. was also observed, suggesting independence of the two types of mouth plasticity. By introducing these new species to the Pristionchus model system, this study provides further insight into the evolution of polymorphisms and their evolutionary intermediates. © 2013 The Linnean Society of London  相似文献   

10.
The flies of the genus Dicranosepsis from Vietnam were investigated and classified taxonomically. Six new species (D. longa sp. nov., D. kurahashii sp. nov., D. monoseta sp. nov., D. sinuosa sp. nov., D. barbata sp. nov., and D. vietnamensis sp. nov.) are described and illustrated. Dicranosepsis is redefined and a revised key to the species is also provided.  相似文献   

11.
A new genus and species of a short limbed and slightly elongate gymnophthalmid lizard is described from the Atlantic rain forests of north-eastern Brazil. The new genus is also characterized by short and stout pentadactyl limbs, presence of prefrontals, absence of frontoparietals, distinctive ear opening and eyelid, two pairs of genials, a distinct collar, smooth, quadrangular, dorsal scales, quadrangular ventrals, fused postfrontal and postorbital bones, and two pairs of sternal ribs. The geographical distribution of the new taxon extends from the state of Rio Grande do Norte to the northern bank of the Rio São Francisco in the state of Alagoas. All specimens were obtained in leaf litter, an observation which agrees with the fossorial habits suggested by the body shape and massive aspect of the head of this species. A phylogenetic analysis based on external morphology, osteology, and molecular data recovered the new lizard as the sister genus to Anotosaura , and Colobosauroides as the sister group to these two.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 144 , 543−557.  相似文献   

12.
Aim  To determine if the distributions of lizard species from Seasonally Dry Tropical Forest (SDTF) enclaves within the Cerrado biome in central Brazil are associated with the Tropical Seasonal Forests Region, a recently proposed phytogeographic unit of South America, corroborating the existence of a Pleistocenic Arc of SDTFs.
Location  SDTF remnants in the Paranã River valley, municipality of São Domingos, Goiás, Brazil.
Methods  Lizards were extensively sampled using haphazard sampling, funnel traps, and pitfall traps with drift fences during four expeditions. The composition of the SDTF lizard assemblage was compared with those from other South American phytogeographic regions (Caatinga, Cerrado, Chaco, Llanos, and the dry forests of Colombia and Bolivia), based on the literature and our own unpublished data.
Results  The SDTF lizard assemblage contained 20 species, including 11 species with extensive distributions among the regions considered, seven species shared exclusively with Cerrado localities, a single species shared exclusively with other SDTFs, and one endemic species. The presence of Lygodactylus klugei (Smith, Martin & Swain, 1977), presumably endemic to the Pleistocenic Arc formed by the Tropical Seasonal Forests Region, considerably extends the known distribution of this species, suggesting historical connections between Caatinga and Cerrado SDTF enclaves.
Main conclusions  The composition of the lizard assemblage in Cerrado SDTF enclaves seems to corroborate the recent proposal that the SDTF should be recognized as a phytogeographic unit (or dominium). The presence of disjunct populations and endemic species highlights the urgency of considering the uniqueness of the Paranã River valley SDTFs and the importance of its conservation.  相似文献   

13.
The tribe Cercosaurini is one of the most poorly studied groups of the lizard family Gymnophthalmidae. Recent studies have suggested that two cercosauriine genera, Neusticurus and Proctoporus , are polyphyletic. The aim of the current study was to rectify the polyphyletic relationships and construct a phylogenetic taxonomy of the Cercosaurini that is congruent with evolutionary history. Neusticurus is divided into two genera, one of them new ( Potamites ), based on the clades recovered by molecular studies and previously discussed morphological data. Proctoporus is divided into three genera, one of which is new ( Petracola ), while an older name ( Riama ) is resurrected for another. All five genera are described and defined and taxonomic keys are presented. This study represents an important advance in rectifying the taxonomy of the Cercosaurini. Many other para- and polyphyletic genera remain in the Gymnophthalmidae and much future work on this group is warranted.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 405–416.  相似文献   

14.
Two new species of the parasitoid wasp genus Trichospilus (Chalcidoidea: Eulophidae: Eulophinae) are described from Java and Sulawesi, Indonesia. A key to all species of Trichospilus worldwide is provided.  相似文献   

15.
A new species of the basal mosasaurid Halisaurus from the Late Cretaceous (Late Maastrichtian) of the Oulad Abdoun Phosphate Basin of Morocco is described on the basis of both cranial and postcranial remains. H. arambourgi sp. nov. is characterized by unique features of the nares, frontal, parietal, girdle and limb bones. A phylogenetical analysis supports the monophyletic status of Halisaurus ; H. platyspondylus (Maastrichtian, New Jersey), H. ortliebi (Maastrichtian, Belgium) and H. arambourgi form an unresolved polytomy. This study does not support the attribution of ' Halisaurus ' sternbergii (Santonian, Kansas) to Halisaurus nor to any known genus. A new genus, Eonatator , is proposed for the reception of this species, Eonatator sternbergii comb. nov. The new taxon Halisaurinae ( Halisaurus  +  Eonatator ) is the sister-group of more advanced mosasaurids (Natantia). Halisaurines are defined by the shape of the lateral premaxilla–maxilla suture; an oblique contact plane between the parietal and the supratemporal; a preaxial ridge present on the distal two-thirds of the radius length; and tibia and fibula long and slender with slightly expanded extremities.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 447–472.  相似文献   

16.
Complete mitochondrial (mt) genomes were sequenced from representatives of three lacertid lizards: Podarcis siculus, Podarcis muralis and Phoenicolacerta kulzeri. In all three genomes the arrangement of the 22 tRNAs, the two rRNAs and the 13 protein‐coding genes conforms to the common vertebrate arrangement. The phylogenetic position of Lacertidae within the order Squamata was determined through sequence analyses based on large sections of complete mt genomes. The number of nucleotide sites used for tree construction was 9234 when outgroup taxa were included, and 10 499 when only Squamata were compared. The phylogenetic analyses confirmed the sister group relationship between Lacertidae and Amphisbaenia as previously proposed on the basis of molecular data. Additionally, Bayesian analysis revealed a well supported clade comprising (Gekkonidae (Lacertidae + Amphisbaenia)), which is not in accordance with the traditional morphological view and most of the previous molecular studies. It confirms, however, the close relationship between Gekkonidae and Amphisbaenia as revealed in a recent study based on complete mt genomes from a smaller number of taxa. Intra‐ and intergeneric sequence comparisons of six commonly used marker genes showed rather high levels of divergence within the Lacertidae. In the intrageneric comparison the control region proved to be considerably more conserved than the protein coding genes.  相似文献   

17.
The systematics of the viviparid freshwater snail genus Margarya endemic to the ancient lakes of Yunnan, China, is revised based on comparative analyses of morphological features, including shell, operculum, radula, and genital anatomy, and molecular phylogenetic analyses of partial sequences of the mitochondrial 16S rDNA (16S) and cytochrome c oxidase subunit I (COI) genes, as well as the nuclear Internal Transcribed Spacer 2 (ITS2). The taxonomic utility of key anatomical and morphological features in this group is evaluated. The genus Margarya as delimited previously is split into three genera in order to retain monophyletic taxa: (1) Margarya s.s., consisting of four species, i.e. the type species Margarya melanioides plus Margarya francheti, Margarya oxytropoides, and Margarya monodi; (2) the previously introduced subgenus Tchangmargarya is elevated to an independent genus containing two species, Tchangmargarya yangtsunghaiensis and the new species T changmargarya multilabiata sp. nov. ; and (3) a new genus, A nularya gen. nov. , is described, also containing two species, i.e. Anularya mansuyi and Anularya bicostata. Molecular phylogenies based on analyses of three gene fragments have identical topologies, supporting the monophyly of these genera. The sister group of Margarya s.s. is Cipangopaludina, whereas the sister group of Anularya is Sinotaia; Tchangmargarya is sister to a clade containing all the aforementioned groups. Features of the operculum and the right male tentacle (penis) are particularly informative on the generic level, whereas shell and radular characters are especially useful to differentiate species. The phylogenetic relationships recovered here are consistent with orogenic patterns of the Yunnan Mountains. Changes in the river system and water area of ancient lakes caused by tectonic activities probably play an important role in speciation and shaping the current pattern of species distribution in Yunnan. © 2015 The Linnean Society of London  相似文献   

18.
The genus Thambemyia Oldroyd is revised. Five species are recognized. Three new species –T. bisetosa, T. bruneiensis and T. hui– are described, and T. pagdeni Oldroyd, 1956 is redescribed. A new subgenus is founded for one new Japanese species, T. (Prothambemyia) japonica. A key to all known species of the genus is provided. Their distributions are also discussed.  相似文献   

19.
From studies in the field, botanic garden and herbarium we concluded that the following four species of Dryopteris grow on the Canary Islands: D. aemula (n = 41) so far found only on Gomera; D. pseudomas (n = 82, apogamous) similarly recorded only for Gomera; D. oligodonta (n = 41) the most common representative of the genus in the Islands is possibly an old Canary endemic related to some African species; D. guanchica a new tetraploid species ( n = 82) hitherto confused with D. austriaca (D. dilatata). On four islands of the Azores the following were found: D. aemula (n = 41); D. azorica (n = 41); D. pseudomas (n = 82, apogamous); and D. crispifolia a new tetraploid species ( n = 82) which is very distinct when living but in the dried pressed state is difficult to differentiate from D. austriaca and D. guanchica.  相似文献   

20.
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