Chamaeleo incognitus or Chamaeleo ignotus? Questioning the taxonomic validity of a new chameleon species

Background Trapelus agilis consists of different morphotypes with restricted distributions in the Iranian Plateau. The phylogeny of the species complex has not been resolved so far, but recently Trapelus sanguinolentus were elevated from this complex into a full species. Other populations of the species complex need to be evaluated taxonomically.MethodsIn the present study, several populations of this species complex along with specimens of its closely related taxa in Iran, T. sanguinolentus, T. ruderatus and T. persicus, were examined using partial nucleotide sequences of two mitochondrial genes (cytb and ND2) (total length 1,322 bp).ResultPopulations of T. sanguinolentus clustered within the T. agilis species complex, thus indicating its paraphyly, but T. sanguinolentus was previously determined to be a species based on morphological features. The T. agilis species complex forms two distinct major clades, each of which is represented by several local populations on the Iranian Plateau. At least five distinct taxa can be identified within this traditional group. Our biogeographic evaluation of the molecular dataset suggested that the Trapelus complex originated in the Late Oligocene (30 mya) and subsequently diversified during the early to middle Miocene (22–13 mya). At first, the predominantly western clade of Trapelus ruderatus diverged from the other clades (22 mya). Afterward, Trapelus persicus diverged around 18 mya ago. The broader T. agilis complex started to diverge about 16 mya, forming several clades on the Iranian Plateau and in Central Asia. The different lineages within this species complex appear to be the result of vicariance events and dispersal waives. The corresponding vicariance events are the formation of the Zagros and Kopet Dagh basins (16–14 mya), and consequently, the aridification of the Iranian Plateau in the late Miocene (11–6 Mya).

The present work is a thorough investigation of the degree of reproductive isolation between Meccus mazzottii and Meccus longipennis, Meccus picturatus, Meccus pallidipennis and Meccus bassolsae, as well as between M. longipennis and M. picturatus. We examined fertility and segregation of morphological characteristics in two generations of hybrids derived from crosses between these species. The percentage of pairs with (fertile) offspring was highest in the set of crosses between M. longipennis and M. picturatus, and lowest between M. mazzottii and M. picturatus. Most first-generation (F1) individuals from crosses involving M. mazzottii were morphologically similar to this species, while only F1 x F1 progeny of parental crosses between M. mazzottii and M. longipennis had offspring second generation that looked like M. mazzottii. The results indicate that different degrees of reproductive isolation apparently exist among the species of the Phyllosoma complex examined in this study. The biological evidence obtained in this study does not support the proposal that M. longipennis and M. picturatus are full species. It could indicate on the contrary, that both could be considered as subspecies of a single polytypic species. On the other hand, biological evidence supports the proposal that M. mazzottii is a full species.

Alexandrium ostenfeldii (Paulsen) Balech and Tangen and A.peruvianum (Balech and B.R. Mendiola) Balech and Tangen are morphologically closely related dinoflagellates known to produce potent neurotoxins. Together with Gonyaulax dimorpha Biecheler, they constitute the A.ostenfeldii species complex. Due to the subtle differences in the morphological characters used to differentiate these species, unambiguous species identification has proven problematic. To better understand the species boundaries within the A.ostenfeldii complex we compared rDNA data, morphometric characters and toxin profiles of multiple cultured isolates from different geographic regions. Phylogenetic analysis of rDNA sequences from cultures characterized as A.ostenfeldii or A.peruvianum formed a monophyletic clade consisting of six distinct groups. Each group examined contained strains morphologically identified as either A.ostenfeldii or A.peruvianum. Though key morphological characters were generally found to be highly variable and not consistently distributed, selected plate features and toxin profiles differed significantly among phylogenetic clusters. Additional sequence analyses revealed a lack of compensatory base changes in ITS2 rRNA structure, low to intermediate ITS/5.8S uncorrected genetic distances, and evidence of reticulation. Together these data (criteria currently used for species delineation in dinoflagellates) imply that the A.ostenfeldii complex should be regarded a single genetically structured species until more material and alternative criteria for species delimitation are available. Consequently, we propose that A.peruvianum is a heterotypic synonym of A.ostenfeldii and this taxon name should be discontinued.

Forpus xanthopterygius is a polytypic species that ranges through most of South America. Currently, it comprises five subspecies: F. x. xanthopterygius, F. x. crassirostris, F. x. spengeli, F. x. flavissimus, and F. x. flavescens. Previous studies that have revised the taxonomy of this complex used a limited number of specimens, hence disagreements about allocation of specific or subspecific status, and even the validity of some taxa, continue. Here, we revise the taxonomy of the Forpus xanthopterygius complex based on morphological and morphometric characters. We analyzed 518 specimens from the entire species geographical distribution. Our results allowed us to propose the recognition of two valid taxa that we suggest to be treated as full species (Forpus xanthopterygius and Forpus spengeli). Forpus xanthopterygius shows great phenotypic variability, in which the plumage is brighter and yellowish in drier habitats and dull and darker in humid ones; nevertheless, this variation has no taxonomic significance.

Taxonomic status of Myotis extremus (Chiroptera, Vespertilionidae) from Mesoamerica, with comments on the distribution and systematics of Myotis nigricans

Strict allopatric speciation of sky island Pyrrhula erythaca species complex

Phylogeography of the Vermilion Flycatcher species complex: Multiple speciation events, shifts in migratory behavior, and an apparent extinction of a Galápagos-endemic bird species

The taxonomic history of Euryoryzomys legatus has been complex and controversial, being either included in the synonymy of other oryzomyine species or considered as a valid species, as in the most recent review of the genus. Previous phylogenetic analyses segregated E. legatus from E. russatus, its putative senior synonym, but recovered it nested within E. nitidus. A general lack of authoritative evaluation of morphological attributes, details of the chromosome complement, or other data types has hampered the ability to choose among alternative taxonomic hypotheses, and thus reach a general consensus for the status of the taxon. Herein we revisit the status of E. legatus using an integrated approach that includes: (1) a morphological review, especially centered on specimens from northwestern Argentina not examined previously, (2) comparative cytogenetics, and (3) phylogenetic reconstruction, using mitochondrial genes. Euryoryzomys legatus is morphologically and phylogenetically distinct from all other species-level taxa in the genus, but its 2n=80, FN=86 karyotype is shared with E. emmonsae, E. nitidus, and E. russatus. Several morphological and morphometric characters distinguish E. legatus from other species of Euryoryzomys, and we provide an amended diagnosis for the species. Morphological characters useful in distinguishing E. legatus from E. nitidus, its sister taxon following molecular analyses, include: larger overall size, dorsal fur with a strong yellowish brown to orange brown tinge, flanks and cheeks with an orange lateral line, ventral color grayish-white with pure white hairs present only on the chin, presence of a thin blackish eye-ring, tail bicolored, presence of an alisphenoid strut and a well-developed temporal and lambdoid crests in the skull, and a labial cingulum on M3. Molecular phylogenetic analyses recovered E. legatus as a monophyletic group with high support nested within a paraphyletic E. nitidus; genetic distances segregated members of both species, except for an exemplar of E. nitidus. Our integrated analyses reinforce E. legatus as a full species, but highlight that E. macconnelli, E. emmonsae, and E. nitidus each may be a species complex and worthy of systematic attention. Finally, we also evaluated the chromosome evolution of the genus within a phylogenetic context.

The time associated with speciation varies dramatically among lower vertebrates. The nature and timing of divergence is investigated in the fantastic dwarf gecko Sphaerodactylus fantasticus complex, a nominal species that occurs on the central Lesser Antillean island of Guadeloupe and adjacent islands and islets. This is compared to the divergence in the sympatric anole clade from the Anolis bimaculatus group. A molecular phylogenetic analysis of numerous gecko populations from across these islands, based on three mitochondrial DNA genes, reveals several monophyletic groups occupying distinct geographical areas, these being Les Saintes, western Basse Terre plus Dominica, eastern Basse Terre, Grand Terre, and the northern and eastern islands (Montserrat, Marie Galante, Petite Terre, Desirade). Although part of the same nominal species, the molecular divergence within this species complex is extraordinarily high (27% patristic distance between the most divergent lineages) and is compatible with this group occupying the region long before the origin of the younger island arc. Tests show that several quantitative morphological traits are correlated with the phylogeny, but in general the lineages are not uniquely defined by these traits. The dwarf geckos show notably less nominal species-level adaptive radiation than that found in the sympatric southern clade of Anolis bimculatus, although both appear to have occupied the region for a broadly similar period of time. Nevertheless, the dwarf gecko populations on Les Saintes islets are the most morphologically distinct and are recognized as a full species (Sphaerodactylus phyzacinus), as are anoles on Les Saintes (Anolis terraealtae).

We use a combination of phylogenetic analysis of mtDNA sequences and multivariate morphometrics to investigate the phylogeography and systematics of the Egyptian cobra (Naja haje) species complex. Phylogenetic analysis of mitochondrial haplotypes reveals a highly distinct clade of haplotypes from the Sudano–Sahelian savanna belt of West Africa, and that the haplotypes of Naja haje arabica form the sister group of North and East African N. h. haje. Multivariate morphometrics confirm the distinctness of the Arabian populations, which are consequently recognised as a full species, Naja arabica Scortecci. The Sudano-Sahelian populations are also found to represent a morphologically distinct taxon, and thus a separate species, which we describe as Naja senegalensis sp. nov. The new species differs from all other members of the N. haje complex by a combination of colour pattern and scalation characteristics (especially higher numbers of scale rows around the neck), and the possession of a unique clade of mtDNA haplotypes. The distribution of the new species includes savanna areas of West Africa, from Senegal to western Niger and Nigeria.

Fritz, U., Branch, W. R., Hofmeyr, M. D., Maran, J., Prokop, H., Schleicher, A., Široký, P., Stuckas, H., Vargas‐Ramírez, M., Vences, M. & Hundsdörfer, A. K. (2010). Molecular phylogeny of African hinged and helmeted terrapins (Testudines: Pelomedusidae: Pelusios and Pelomedusa). —Zoologica Scripta, 40, 115–125.With 18 currently recognised species, Pelusios is one of the most speciose chelonian genera worldwide, even though the taxonomy of some species is contentious. Recent investigations suggested that the closely related, but morphologically distinct genus Pelomedusa is paraphyletic with respect to Pelusios, and that Pelomedusa consists of nine deeply divergent lineages. Using three mitochondrial and three nuclear DNA fragments (2054 bp mtDNA, 2025 bp nDNA), we examined for the first time the phylogeny of Pelusios by molecular means. Our analyses included all Pelusios species, except the probably extinct P. seychellensis, as well as the nine Pelomedusa lineages. The results showed that Pelusios and Pelomedusa are reciprocally monophyletic. Limited sampling of Pelusios species and homoplasy introduced by remote outgroups most likely explain the paraphyly of Pelomedusa in previous studies. The distinctiveness of most Pelusios species was confirmed, but none of the currently recognised species groups within Pelusios was monophyletic. In Pelusios rhodesianus and P. sinuatus distinct genetic lineages were discovered, suggestive of cryptic taxa. In contrast, the recognition of the weakly differentiated P. castaneus and P. chapini as full species is doubtful, as is the validity of the Malagasy and Seychellois subspecies of P. castanoides. GenBank sequences of P. williamsi were nested within P. castaneus, but the morphological distinctiveness of the two species makes it likely that the GenBank sequences (derived from a turtle from the pet trade) are misidentified. Divergence among the distinct genetic lineages of Pelomedusa equals or exceeds the differences among Pelusios species, supporting the view that Pelomedusa is a species complex.

We addressed the evolutionary relationships and biogeographical patterns of a model organism of low relative dispersal ability by electrophoretically assaying the products of 42 presumptive gene loci in Philippine and Bornean members of the Rana signata complex of SE Asian stream frogs. Utilizing three distantly related species of ranid frogs to deeply root trees consisting of five more closely-related species and six in-group species of the Rana signata complex, we conducted phylogenetic analyses that produced concordant topologies, regardless of the data coding strategy employed. All analyses support the hypothesis of monophyly for the Rana signata complex on the whole, but none provides support for the monophyly of its Philippine members. Our analyses of morphometric and allozyme data (along with biogeographical information) indicate that (1) most previously-recognized Philippine and Bornean subspecies of the Rana signata complex should be recognized as full species in appreciation of their status as independent evolutionary lineages; (2) Rana picturata Boulenger (until very recently included in the synonymy of Rana signata signata) is deserving of specific rank; (3) the Mindoro Isl. (Philippine) population, previously confused with Rana signata similis of Luzon Isl. is a new species; (4) two major clades (((R. signata (R. grandocula + R. similis)) + (R. picturata (R. mangyanum + R. moellendorffi))) of Bornean + Philippine lineages are recognized, corresponding to two separate faunal exchanges between the Philippines and the edge of the Sunda Shelf; (5) invasions of the oceanic portions of the Philippine islands from the Sunda Shelf have occurred along both the eastern (Sulus–Mindanao–Samar–Leyte–Luzon) arc and the western (Palawan–Busuanga–Mindoro) island arcs; (6) northern reaches of Wallace's Line (as modified by Huxley) include exceptions to an otherwise discrete faunal separation. These results suggest the need for revision of this biogeographical barrier, increased recognition of temporal patterns of island connectedness and geographical proximity, and/or a greater appreciation of dispersal abilities of ranid frogs.

We addressed the evolutionary relationships and biogeographical patterns of a model organism of low relative dispersal ability by electrophoretically assaying the products of 42 presumptive gene loci in Philippine and Bornean members of the Rana signata complex of SE Asian stream frogs. Utilizing three distantly related species of ranid frogs to deeply root trees consisting of five more closely-related species and six in-group species of the Rana signata complex, we conducted phylogenetic analyses that produced concordant topologies, regardless of the data coding strategy employed. All analyses support the hypothesis of monophyly for the Rana signata complex on the whole, but none provides support for the monophyly of its Philippine members. Our analyses of morphometric and allozyme data (along with biogeographical information) indicate that (1) most previously-recognized Philippine and Bornean subspecies of the Rana signata complex should be recognized as full species in appreciation of their status as independent evolutionary lineages; (2) Rana picturata Boulenger (until very recently included in the synonymy of Rana signata signata) is deserving of specific rank; (3) the Mindoro Isl. (Philippine) population, previously confused with Rana signata similis of Luzon Isl. is a new species; (4) two major clades (((R. signata (R. grandocula + R. similis)) + (R. picturata (R. mangyanum + R. moellendorffi))) of Bornean + Philippine lineages are recognized, corresponding to two separate faunal exchanges between the Philippines and the edge of the Sunda Shelf; (5) invasions of the oceanic portions of the Philippine islands from the Sunda Shelf have occurred along both the eastern (Sulus–Mindanao–Samar–Leyte–Luzon) arc and the western (Palawan–Busuanga–Mindoro) island arcs; (6) northern reaches of Wallace's Line (as modified by Huxley) include exceptions to an otherwise discrete faunal separation. These results suggest the need for revision of this biogeographical barrier, increased recognition of temporal patterns of island connectedness and geographical proximity, and/or a greater appreciation of dispersal abilities of ranid frogs.

Several animal species have recently been shown to have hybrid origins, but no avian examples have been documented with molecular evidence. We investigate whether the Audubon's warbler (Dendroica auduboni), one of four visually distinct species in the yellow-rumped warbler complex, has originated through hybridization between two other species in this group, the myrtle warbler (D.coronata) and black-fronted warbler (D.nigrifrons). Analysis of nuclear amplified fragment length polymorphism (AFLP) and sequence markers shows that Audubon's warblers are genetically intermediate and carry a mixture of alleles otherwise found only in one or the other of their putative parental species. Audubon's warblers also carry two deeply divergent mitochondrial DNA lineages, each shared with only one putative parental form. Broad clines between Audubon's and black-fronted warblers in AFLP markers call into question the validity of these two forms as full species; nevertheless, our results suggest that the Audubon's warbler probably originated through hybridization between two long-diverged species. It is likely that more cases of avian species of hybrid origin will be revealed by surveys of variation in nuclear DNA and other traits.

With robust new datasets from morphology and DNA sequences, we review the limbed, nonpentadactyl species of the Brachymeles samarensis complex (now known to include B. cebuensis, B. minimus, and B. lukbani), and describe five new species in this highly limb-reduced, endemic Philippine clade of scincid lizards. For more than four decades, B. samarensis has been recognized as a single “widespread” species. This perception of the species' peculiar geographic range has persisted as a result of weak sampling and similar gross morphology (body sizes, scale pigmentation) among populations. However, previous authors have noted morphological variation between different island populations, and our new data build on these observations and extend them to delimit new proposed species boundaries. Our data indicate that the “widespread” species B. samarensis is actually a complex of six distinct lineages, some of which are not each others' closest relatives, and each of which is genetically unique. The taxa we define possess allopatric geographic ranges and differ from their congeners by numerous diagnostic characters of external morphology, and therefore should be recognized as full species in accordance with any lineage-based species concept. Species diversity in the genus has doubled in the last 3 yr, with these six taxa increasing the total known number of species of Brachymeles to 30.