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1.
The monophyly of the Sceloporus variabilis group is well established with five species and two species complexes, but phylogenetic relationships within species complexes are still uncertain. We studied 278 specimens in 20 terminals to sample all taxa in the “variabilis group,” including three subspecies in the “variabilis complex,” and two outgroups (Sceloporus grammicus and Sceloporus megalepidurus). We assembled an extensive morphological data set with discrete and continuous characters (distances and scale counts), including geometric morphometric data (landmark coordinates of three shapes), and a three‐marker molecular data set as well (ND4, 12S and RAG1). We conducted parsimony and Bayesian phylogenetic inferences on these data, including several partitioning and weighting schemes. We suggest elevating three subspecies to full species status. Therefore, we recommend recognition of nine species in the “variabilis group.” First, S. variabilis is sister to Sceloporus teapensis. In turn, Sceloporus cozumelae is sister to Sceloporus olloporus. These four species are a monophyletic group, which is sister to Sceloporus smithi. Finally, Sceloporus marmoratus is sister of the clade of five species. The other species in the “variabilis group” (Sceloporus chrysostictus, Sceloporus couchii and Sceloporus parvus) are a paraphyletic grade at the base of the tree. Our analyses reject the existence of the “variabilis complex.” We conducted a parsimony‐based ancestral reconstruction on body size (snout–vent length), femoral pores and dorsal scales and related morphological changes to geographic distribution of the species. Our phylogenetic hypothesis will allow best designs of comparative studies with species in the “variabilis group,” one of the earliest divergent lineages in the genus.  相似文献   

2.
The existence of two or more distinctly coloured phenotypes among individuals of an interbreeding population is known as colour polymorphism. In amphibians, this phenomenon is pervasive among anurans, but rare or absent among salamanders and caecilians, respectively. Here, we examine whether various distinct phenotypes of Salamandra salamandra in North Spain, used as a basis to describe the subspecies S. s. bernardezi and S. s. alfredschmidti, indeed warrant separate taxonomic status or that these co‐occur and belong to a single taxon. Based on a sample of 1147 individuals from 27 local populations, six phenotype classes were designated. Although two phenotypes that are attributable to S. s. alfredschmidti show some degree of geographical restriction, these co‐occur with those representing typical S. s. bernardezi. A fifth phenotype class could not be unambiguously attributed to either subspecies due to an overlap in previously suggested diagnostic characteristics. Mitochondrial (cytochrome b) and nuclear (β‐fibrinogen) DNA analyses revealed S. s. alfredschmidti to be nested within several subclades of S. s. bernardezi, without displaying unique lineages. Furthermore, no significant divergence was recovered by means of niche overlap analyses. As a result, we revoke the subspecies status of S. s. alfredschmidti, which should be regarded as a junior synonym of S. s. bernardezi. The current findings confirm the existence of colour polymorphism in S. salamandra and the family Salamandridae, which provides exciting possibilities for future research.  相似文献   

3.
A new species of the genusSanicula (sect.Sanicoria) endemic to the southern Sierra Juárez of Baja California, Mexico, is described and illustrated.Sanicula moranii resemblesS. deserticola andS. bipinnatifida, but has thicker basal leaves, with broader petioles and rachises, and shorter fruit prickles that are confined to the apical part of the mericarps. The taxonomic relationships of these species are discussed, along with aspects of their distribution and habitat.
Resumen  Una neuva especie del géneroSanicula (secciónSanicoria) endémica de la Sierra Juárez de Baja California, México, es descrita e ilustrada.Sanicula moranii presenta similitud conS. deserticola yS. bipinnatifida, no obstante tiene gruesas hojas basales con pecíolos y raquis anchos, y espínulas del fruto más cortas que se distribuyen únicamente en la parte apical de los mericarpos. Además, se comentan las relaciones taxonómicas de las tres especies, así como algunos aspectos de sus distribuciones y hábitats.
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Wu, H.‐C., Lin, R.‐C., Hung, H.‐Y., Yeh, C.‐F., Chu, J.‐H., Yang, X.‐J., Yao, C.‐J., Zou, F.‐S., Yao, C.‐T., Li, S.‐H. & Lei, F.‐M. (2011). Molecular and morphological evidences reveal a cryptic species in the Vinaceous Rosefinch Carpodacus vinaceus (Fringillidae; Aves). —Zoologica Scripta, 40, 468–478. The Vinaceous Rosefinch (Carpodacus vinaceus) is endemic in East Asia with two recognized subspecies –C. v. vinaceus, distributed along the eastern edge of the Tibetan Plateau and the Himalayas, and C. v. formosanus, restricted to Taiwan’s Central Mountain Range. As reflected in a controversial taxonomic history, this vastly disjunctive distribution pattern suggests that the subspecies, having been isolated from each other for a long time, might have diverged, challenging the current taxonomic treatment and calling for possible species delimitation. Sequences of two mitochondrial fragments (mtDNA) and two Z‐linked nuclear loci (zDNA) were used to reconstruct the intraspecific phylogeny of C. vinaceous. The mtDNA tree shows that the two subspecies of the vinaceous rosefinch form two exclusively monophyletic clades. All but one zDNA sequences from the nominate subspecies and C. v. formosanus also formed exclusively monophyletic clades (the exceptional zDNA sequence from C. v. vinaceous formed a weakly supported clade with two outgroup species). Moreover, by conducting quantitative comparisons of morphometric traits and male plumage coloration, we found that the two subspecies exhibit distinguishable morphological differences. All the evidence therefore suggests that C. v. formosanus is a cryptic species and that its taxonomic status should be restored to full species. Molecular dating suggests that the two sibling rosefinches split 1.7 ± 0.2 million years ago, providing a point estimate for the historical connectivity of biota between eastern Tibet‐Himalayas and montane Taiwan.  相似文献   

7.
Recent analyses of molecular markers have significantly revised the traditional taxonomy of Podarcis species (Squamata: Lacertidae), leading to critically reconsider the taxonomic value of several subspecies described only on morphological bases. In fact, lizards often exhibit high morphological plasticity both at the intra‐specific and the intra‐population level, especially on islands, where phenotypic divergences are mainly due to local adaptation, rather than to evolutionary differentiation. The Common wall lizard Podarcis muralis exhibits high morphological variability in biometry, pholidosis values and colour pattern. Molecular analyses have confirmed the key role played by the Italian Peninsula as a multi‐glacial refuge for P. muralis, pointing out the lack of congruence between mitochondrial lineages and the four peninsular subspecies currently recognized. Here, we analyse a portion of the protein‐encoding cytochrome b gene in the seven subspecies described for the Tuscan Archipelago (Italy), in order to test whether the mitochondrial haplotypes match the morphologically based taxonomy proposed for Common wall lizard. We also compare our haplotypes with all the others from the Italian Peninsula to investigate the presence of unique genetic lineages in insular populations. Our results do not agree completely with the subspecific division based on morphology. In particular, the phylogenetic analyses show that at least four subspecies are characterized by very similar haplotypes and fall into the same monophyletic clade, whereas the other three subspecies are closer to peninsular populations from central Italy. From these results, we conclude that at least some subspecies could be better regarded as simple eco‐phenotypes; in addition, we provide an explanation for the distinctiveness of exclusive lineages found in the archipelago, which constituted a refuge for this species during last glacial periods.  相似文献   

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The genus Homonota was described by Gray (1845) and currently includes 10 species: Homonota andicola, H. borellii, H. darwinii, H. fasciata, H. rupicola, H. taragui, H. underwoodi, H. uruguayensis, H. williamsii & H. whitii and one subspecies of H. darwinii (H. darwinii macrocephala). It is distributed from 15° latitude south in southern Brazil, through much of Bolivia, Paraguay, Uruguay and Argentina to 54° south in Patagonia and across multiple different habitats. Several morphological taxonomic studies on a subset of these species have been published, but no molecular phylogenetic hypotheses are available for the genus. The objective of this study is to present a molecular phylogenetic hypothesis for all the described species in the genus. We sequenced two mitochondrial genes (cyt‐b & 12S: 1745 bp), seven nuclear protein coding (RBMX, DMLX, NKTR, PLRL, SINCAIP, MXRA5, ACA4: 5804 bp) and two anonymous nuclear loci (30Hb, 19Hb: 1306 bp) and implemented traditional concatenated analyses (MP, ML, BI) as well as species‐tree (*beast ) approaches. All methods recovered almost the same topology. We recovered the genus Homonota as monophyletic with strong statistical support. Within Homonota, there are three strongly supported clades (whitii, borellii and fasciata), which differ from those previously proposed based on scale shape, osteology, myology and quantitative characters. Detailed morphological analyses based on this highly resolved and well‐supported phylogeny will provide a framework for understanding morphological evolution and historical biogeography of this phenotypically conservative genus. We hypothesize that extensive marine transgressions during Middle and Late Miocene most probably isolated the ancestors of the three main clades in eastern Uruguay (borellii group), north‐western Argentina‐southern Bolivia (fasciata group), and central‐western Argentina (whitii group). Phylogeographic and morphological/morphometric analyses coupled with paleo‐niche modelling are needed to better understand its biogeographical history.  相似文献   

10.
The commercial deep‐sea penaeid shrimp genus Parapenaeus contains 15 species, three subspecies and two forms in the Indo‐West Pacific and the Atlantic. Novel nucleotide sequence data from five different genes (COI, 16S, 12S, NaK and PEPCK) were collected to estimate phylogenetic relationships and taxonomic status amongst all but one subspecies in this genus. The phylogenetic results only support two of the four species groups previously proposed for this genus and indicate an evolution direction of the genital organs from simple to complex. The present results suggest that Parapenaeus originated in the shallow waters of the West Pacific with subsequent migration to the deep sea and the Atlantic. The molecular data reveal that there was probably misidentification of females between Parapenaeus australiensis and Parapenaeus ruberoculatus, with females previously assigned as P. australiensis likely being the females of P. ruberoculatus, while material identified as P. australiensis forma nodosa being the true P. australiensis females. On the other hand, Parapenaeus longipes forma denticulata truly represents a variation of the same species, while the subspecies Parapenaeus fissuroides indicus warrants a specific rank.  相似文献   

11.
We performed a comparison of molecular and morphological diversity in a freshwater colonial genus Synura (Chrysophyceae, Stramenopiles), using the island of Newfoundland (Canada) as a case study. We examined the morphological species diversity in collections from 79 localities, and compared these findings to diversity based on molecular characters for 150 strains isolated from the same sites. Of 27 species or species-level lineages identified, only one third was recorded by both molecular and morphological techniques, showing both approaches are complementary in estimating species diversity within this genus. Eight taxa, each representing young evolutionary lineages, were recovered only by sequencing of isolated colonies, whereas ten species were recovered only microscopically. Our complex investigation, involving both morphological and molecular examinations, indicates that our knowledge of Synura diversity is still poor, limited only to a few well-studied areas. We revealed considerable cryptic diversity within the core S. petersenii and S. leptorrhabda lineages. We further resolved the phylogenetic position of two previously described taxa, S. kristiansenii and S. petersenii f. praefracta, propose species-level status for S. petersenii f. praefracta, and describe three new species, S. vinlandica, S. fluviatilis, and S. cornuta. Our findings add to the growing body of literature detailing distribution patterns observed in the genus, ranging from cosmopolitan species, to highly restricted taxa, to species such as S. hibernica found along coastal regions on multiple continents. Finally, our study illustrates the usefulness of combining detailed morphological information with gene sequence data to examine species diversity within chrysophyte algae.  相似文献   

12.
Two new species ofSerjania sect.Serjania,Serjania neei from Bolivia andS. rhytidococca from Mexico, are described, illustrated, and compared with their closest relatives.
Resumen  En el presente artículo se describen, se ilustran y se comparan con los parientes mas cercanos las nuevas especiesSerjania neei de Bolivia yS. rhytidococca de México, ambas pertenecientes a la secciónSerjania.
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13.
Several subspecies are defined within Codium fragile, including the invasive C. fragile ssp. fragile, first reported in New Zealand in 1973. An endemic subspecies, C. fragile ssp. novae‐zelandiae, is also found throughout New Zealand. The two subspecies exhibit morphological and molecular variation, although these have never been evaluated together. We compared variation between subspecies at locations in Auckland, identifying subspecies using rps3‐rpl16 DNA sequence data, and assessing gross morphological differences, anatomical utricle characters and morphometrics. The taxonomic utility of the morphometric data sets was assessed by linear discriminant analysis. Utricle characters and measurements varied within individual thalli and between different preservation methods. The phenotypes of both subspecies were highly variable and influenced by environment. Accurate subspecies delimitation using morphological data was not possible; the discriminant analyses performed no better than chance for all combinations of the morphological data. Specimens from New Zealand, Canada, Australia and Ireland were sequenced using both the rps3‐rpl16 and tufA plastid markers. The tufA elongation factor was shown to be a good candidate for differentiating subspecies of C. fragile. This marker is twice the length of the rps3‐rpl16 spacer, shows greater variation between ssp. fragile and novae‐zelandiae, and is less prone to sequencing error. A simple restriction enzyme digest of the tufA amplicon can distinguish ssp. fragile and ssp. novae‐zelandiae. Our study expands the known range of the ssp. fragile in New Zealand, including the first record of this subspecies from the west coast of Auckland, and points to a need to re‐evaluate morphological and molecular criteria for subspecies currently defined within C. fragile.  相似文献   

14.
Ensis Schumacher, 1817 razor shells occur at both sides of the Atlantic and along the Pacific coasts of tropical west America, Peru, and Chile. Many of them are marketed in various regions. However, the absence of clear autapomorphies in the shell and the sympatric distributions of some species often prevent a correct identification of specimens. As a consequence, populations cannot be properly managed, and edible species are almost always mislabelled along the production chain. In this work, we studied whether the currently accepted Atlantic Ensis morphospecies are different evolutionary lineages, to clarify their taxonomic status and enable molecular identifications through DNA barcoding. For this, we studied 109 specimens sampled at 27 sites, which were identified as belonging to nine of those morphospecies. We analysed nucleotide variation at four nuclear (18S, 5.8S, ITS1, and ITS2) and two mitochondrial (COI and 16S) regions, although the 18S and 5.8S regions were not informative at the species level and were not further considered. The phylogenetic trees and networks obtained supported all morphospecies as separately evolving lineages. Phylogenetic trees recovered Ensis at each side of the Atlantic as reciprocally monophyletic. Remarkably, we confirm the co‐occurrence of the morphologically similar E. minor (Chenu, 1843) and E. siliqua (Linné, 1758) along the NW Iberian coast, a fact that has been often overlooked. In South America, a relevant divergence between E. macha (Molina, 1792) individuals from Chile and Argentina was unveiled and suggests incipient speciation. We also confirm the occurrence of the North American species E. directus (Conrad, 1843) as far south as north‐eastern Florida. Among the genomic regions analysed, we suggest COI as the most suitable DNA barcode for Atlantic Ensis. Our results will contribute to the conservation and management of Ensis populations and will enable reliable identifications of the edible species, even in the absence of the valves. The name Ensis coseli Vierna nom. nov. is proposed to replace E. minor Dall, 1899 non (Chenu, 1843).  相似文献   

15.
16.
Gómez‐Moliner, B.J., Elejalde, A.M., Arrébola, J.R., Puente, A.I., Martínez‐Ortí, A., Ruiz, A. & Madeira, MJ. (2012). Molecular phylogeny of the Helicodontidae and Trissexodontidae (Gastropoda). —Zoologica Scripta, 00, 000–000. In this study, we present a molecular phylogeny of the Trissexodontidae and Helicodontidae obtained by means of Maximum Parsimony, Neighbor Joining, Maximum Likelihood and Bayesian analyses of DNA sequences. Nearly 3 KB of sequence data of two mitochondrial genes (COI, 16S rDNA) and the nuclear rRNA gene cluster including ITS‐1, the 3′end of the 5.8S gene, the complete ITS‐2 region and 5′ end of the large subunit 28S were used to reconstruct the phylogeny of these two families. Monophyly of Trissexodontidae and Helicodontidae at the family level is well supported. A new classification of the genera in the Trissexodontidae is proposed. It includes two subfamilies: Gittenbergeriinae (monotypic for Gittenbergeria turriplana) and Trissexodontinae. The latter includes three strongly supported tribes: (i) Trissexodontini, including Mastigophallus, Trissexodon, Oestophorella and Suboestophora; (ii) Oestophorini, with Oestophora; and (iii) Caracollinini, with Caracollina, Gasulliella, Gasullia and Hatumia. The polytypic Oestophora and Suboestophora are recovered as two monophyletic genera. The anatomy of the auxiliary copulatory organs of the reproductive system is coherent with the new taxonomic interpretation of the Trissexodontidae. Further work, including some more taxa is needed to delimitate subfamilies within Helicodontidae. Finally, the addition of some sequences of other Helicoidea shows that the genus Ciliella is not closely related to Trissexodontidae, being grouped within the Hygromiidae, instead.  相似文献   

17.
Male‐biased sexual dimorphism is extensive in New World spiny lizards (Sceloporus: Phrynosomatidae) and is particularly prominent in the polymorphic minor lizard Sceloporus minor. However, the possible relationship between patterns of sexual dimorphism and gonadal development is little known for most species. In this study, we explored aspects of sexual dimorphism in noncolor morphological traits in S. minor and characterized the gonadal cycle in males and females from each of two sites (El Enzuelado and La Manzana) in Hidalgo, México, differing in key ecological aspects linked to life‐history trait expression in other lizards. Males were generally larger than females in each population and expressed larger forms of several other morphological traits, although not all comparisons attained statistical significance. Both sexes attained reproductive maturity at a larger size in El Enzuelado relative to La Manzana, and females from El Enzuelado had larger litters. Gonadal cycles differed substantially between the two populations and suggest that reproductive activity of males and females was synchronous at El Enzuelado and asynchronous at La Manzana, an unusual pattern. Geographic variation in sex‐specific responses to environmental variables may be at least partly responsible for the exceptional species diversity of spiny lizards in México.  相似文献   

18.
Scaphinotus petersi Roeschke, 1907 (Carabidae) is a ground beetle endemic to Sky Islands in south‐eastern Arizona. Previous taxonomic studies described several subspecies with morphological differences inhabiting geographically isolated mountain ranges. We combined molecular sequence data and morphometric data, especially head and pronotum shape analyses, to examine the variation and divergence in subspecies and isolated montane populations. In this study, we employ a combination of distance morphometrics as well as geometric morphometrics to quantify the level of morphological variation, and to test the hypothesis that geographically distinct populations of S. petersi are phenotypically distinct. Results suggest that these isolated populations have diverged morphologically and genetically. Phylogenetic analyses identified two monophyletic lineages within the species that correspond generally to pronotum shape. We observed significant morphological variation among most montane populations in of S. petersi, with the pronotum shape as the clearest delimiting trait. © 2015 The Linnean Society of London  相似文献   

19.
We used both highly variable mitochondrial and nuclear loci to investigate the large mouse‐eared bat species complex in the Western Palaearctic to clarify their systematic position. Although mitochondrial lineages show no species segregation and some haplotypes are shared between Myotis myotis and Myotis blythii sensu lato, Bayesian clustering methods based on multilocus genotypes indicate highly concordant nuclear and morphological species assignment. These multilocus, nuclear analyses detected only a single putative F1 hybrid in the extensive areas of sympatry sampled, thus confirming the biological species status of M. myotis and M. blythii s.l. We propose that the strong cytonuclear discordance in these species complex results from a combination of prior spatial isolation of the two species in different glacial refugia, followed by a succession of mitochondrial introgression events that occurred during the eastward and westward expansions of M. myotis and of M. blythii, respectively. The nuclear markers further indicate the presence of a notable genetic discontinuity within M. myotis that broadly separates populations into an eastern and a western component with an overlap zone in the Balkans. This eastern and western discontinuity is also apparent in the mitochondrial lineages with the D haplogroup largely confined to samples found in Thrace and Asia Minor. None of these genetic discontinuities correspond to the distribution of the two commonly recognized M. myotis subspecies (myotis and macrocephalicus). We also show that distinct morphological subspecies within M. blythii (oxygnathus, omari, risorius and lesviacus) in Europe and the near‐East do not correlate with significant evolutionarily units, whether identified by mitochondrial or nuclear data and thus only represent local morphological variants with little taxonomic relevance.  相似文献   

20.
Phenotypic and genetic variation are present in all species, but lineages differ in how variation is partitioned among populations. Examining phenotypic clustering and genetic structure within a phylogeographic framework can clarify which biological processes have contributed to extant biodiversity in a given lineage. Here, we investigate genetic and phenotypic variation among populations and subspecies within a Neotropical songbird complex, the White‐collared Seedeater (Sporophila torqueola) of Central America and Mexico. We combine measurements of morphology and plumage patterning with thousands of nuclear loci derived from ultraconserved elements (UCEs) and mitochondrial DNA to evaluate population differentiation. We find deep levels of molecular divergence between two S. torqueola lineages that are phenotypically diagnosable: One corresponds to S. t. torqueola along the Pacific coast of Mexico, and the other includes S. t. morelleti and S. t. sharpei from the Gulf Coast of Mexico and Central America. Surprisingly, these two lineages are strongly differentiated in both nuclear and mitochondrial markers, and each is more closely related to other Sporophila species than to one another. We infer low levels of gene flow between these two groups based on demographic models, suggesting multiple independent evolutionary lineages within S. torqueola have been obscured by coarse‐scale similarity in plumage patterning. These findings improve our understanding of the biogeographic history of this lineage, which includes multiple dispersal events out of South America and across the Isthmus of Tehuantepec into Mesoamerica. Finally, the phenotypic and genetic distinctiveness of the range‐restricted S. t. torqueola highlights the Pacific Coast of Mexico as an important region of endemism and conservation priority.  相似文献   

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