Project description:BackgroundThe Qinghai-Tibetan Plateau (QTP) is the world's highest and largest plateau, but the role of its uplift in the evolution of species or biotas still remains poorly known. Toad-headed lizards of the reproductively bimodal genus Phrynocephalus are a clade of agamids, with all viviparous species restricted to the QTP and adjacent regions. The eastern part of the range of the viviparous taxa is occupied by three closely related but taxonomically controversial species, P. guinanensis, P. putjatia and P. vlangalii. Here, we combined genetic (mitochondrial ND4 gene and nine microsatellite loci), morphological (11 mensural and 11 meristic variables), and ecological (nine climatic variables) data to explore possible scenarios that may explain the discordance between genetic and morphological patterns, and to test whether morphological divergence is associated with local adaptation.ResultsWe found weak genetic differentiation but pronounced morphological divergence, especially between P. guinanensis and P. vlangalii. Genetically, the species boundary was not so clear between any species pair. Morphologically, the species boundary was clear between P. guinanensis and P. vlangalii but not between other two species pairs. Body size and scale characters accounted best for morphological divergence between species. Morphological divergence was related to habitat types that differ climatically.ConclusionsOur study provides evidence for genetic and morphological divergence among the three closely related viviparous species of Phrynocephalus lizards, and supports the idea that natural selection in spatially heterogeneous environments can lead to population divergence even in the presence of gene flow. Our study supports the hypothesis that the evolutionary divergence between viviparous Phrynocephalus species was a consequence of environmental change after the uplift of the QTP.
Project description:The scale-worm family Iphionidae consists of four genera. Of these, Thermiphione has two accepted species, both native to hydrothermal vents in the Pacific Ocean; T.fijiensis Miura, 1994 (West Pacific) and T.tufari Hartmann-Schröder, 1992 (East Pacific Rise). Iphionella is also known from the Pacific, and has two recognized species; Iphionellarisensis Pettibone, 1986 (East Pacific Rise, hydrothermal vents) and I.philippinensis Pettibone, 1986 (West Pacific, deep sea). In this study, phylogenetic analyses of Iphionidae from various hydrothermal vent systems of the Pacific Ocean were conducted utilizing morphology and mitochondrial (COI and 16S rRNA) and nuclear (18S and 28S rRNA) genes. The results revealed a new iphionid species, described here as Thermiphionerapanuisp. n. The analyses also demonstrated the paraphyly of Thermiphione, requiring Iphionellarisensis to be referred to the genus, as Thermiphionerisensis (Pettibone, 1986).
Project description:The lyophylloid agarics are a group of ecologically highly diversified macrofungi, some of which are very popular edible mushrooms. However, we know little about lyophylloid species diversity in China. In this study, we described four new species from China: Lyophyllum atrofuscum, L. subalpinarum, L. subdecastes, and Ossicaulis sichuanensis. We conducted molecular phylogenetic analyses of Lyophyllaceae based on the nuclear ribosomal RNA gene (nLSU) and the internal transcribed spacer regions (ITS). Phylogenetic analyses by the maximum likelihood method and Bayesian inference showed that the four new species are unique monophyletic species. A key to the species of Lyophyllum from China and a key to Ossicaulis worldwide were given.
Project description:Pseudallescheria boydii (anamorph Scedosporium apiospermum) is the species responsible for human scedosporiosis, a fungal infection with a high mortality rate and which is difficult to treat. Recently, it has been demonstrated that high genetic variation exists within this species. We have performed a morphological and molecular study involving numerous strains of clinical or environmental origins and from different countries. The analysis of partial sequences of the beta-tubulin (two loci) and calmodulin genes and the internal transcribed spacer region of the rRNA gene has demonstrated that P. boydii is a species complex. The combined analysis of the sequences of the four loci of 60 strains has showed the presence of 44 haplotypes in the in group. Three species morphologically related to P. boydii sensu stricto, i.e., Pseudallescheria angusta, Pseudallescheria ellipsoidea, and Pseudallescheria fusoidea, which had previously been considered synonyms, could be differentiated genetically from P. boydii in our study. It is relevant that two of the three strains now included in P. ellipsoidea have caused invasive infections. The species Pseudallescheria minutispora and Scedosporium aurantiacum are clearly phylogenetically separated from the other species studied and are here proposed as new. Morphological features support this proposal. All the strains included in S. aurantiacum species have a clinical origin, while those included in P. minutispora are environmental. Further studies are needed to demonstrate whether all the species included in the P. boydii complex have different clinical spectra and antifungal susceptibility.
Project description:Shih-Pin Huang, I-Shiung Chen, Mana M. N. Yung, and Kwang-Tsao Shao (2016) Mugilogobius mertoni (Weber, 1911) is considered as a widely distributed species around the Indo- West Pacific region, and several nominal species are considered as junior synonyms of M. mertoni. However, in our recent study, several different morphological types of M. mertoni were observed, they were collected from Taiwan, Palau and Phuket Island. This study aimed to investigate the taxonomic status of those M. mertoni-like individuals, we also attempted to assess their phylogenetic relationship base on combined mitochondrial DNA ND5, Cyt b and D-loop sequences. The present morphological and molecular evidences suggested that the current M. mertoni could be regarded as a species complex, and several cryptic species might be included in M. mertoni complex. One of these which collected from Taiwan is described as a new species, Mugilogobius flavomaculatus n. sp. based on both morphological and molecular evidence in this study. The phylogenetic tree also revealed that M. flavomaculatus n. sp. is the closest to M. mertoni. M. flavomaculatus n. sp. and its sister species M. mertoni are found to have different niches in the same estuary. Moreover, stable morphological characters and nuclear gene RAG2 also clearly show that no hybridization is detected in between M. flavomaculatus n. sp. and M. mertoni. Except the present new species, taxonomic status of all junior synonyms refers to M. mertoni are also discussed.
Project description:Supportive data related to the article "Anonymous nuclear markers reveal taxonomic incongruence and long-term disjunction in a cactus species complex with continental-island distribution in South America" (Perez et al., 2016) [1]. Here, we present pyrosequencing results, primer sequences, a cpDNA phylogeny, and a species tree phylogeny.
Project description:BackgroundWith over 3,500 species encompassing a diverse range of morphologies and ecologies, snakes make up 36% of squamate diversity. Despite several attempts at estimating higher-level snake relationships and numerous assessments of generic- or species-level phylogenies, a large-scale species-level phylogeny solely focusing on snakes has not been completed. Here, we provide the largest-yet estimate of the snake tree of life using maximum likelihood on a supermatrix of 1745 taxa (1652 snake species + 7 outgroup taxa) and 9,523 base pairs from 10 loci (5 nuclear, 5 mitochondrial), including previously unsequenced genera (2) and species (61).ResultsIncreased taxon sampling resulted in a phylogeny with a new higher-level topology and corroborate many lower-level relationships, strengthened by high nodal support values (> 85%) down to the species level (73.69% of nodes). Although the majority of families and subfamilies were strongly supported as monophyletic with > 88% support values, some families and numerous genera were paraphyletic, primarily due to limited taxon and loci sampling leading to a sparse supermatrix and minimal sequence overlap between some closely-related taxa. With all rogue taxa and incertae sedis species eliminated, higher-level relationships and support values remained relatively unchanged, except in five problematic clades.ConclusionOur analyses resulted in new topologies at higher- and lower-levels; resolved several previous topological issues; established novel paraphyletic affiliations; designated a new subfamily, Ahaetuliinae, for the genera Ahaetulla, Chrysopelea, Dendrelaphis, and Dryophiops; and appointed Hemerophis (Coluber) zebrinus to a new genus, Mopanveldophis. Although we provide insight into some distinguished problematic nodes, at the deeper phylogenetic scale, resolution of these nodes may require sampling of more slowly-evolving nuclear genes.
Project description:The family Oscarellidae is one of the two families in the class Homoscleromorpha (phylum Porifera) and is characterized by the absence of a skeleton and the presence of a specific mitochondrial gene, tatC. This family currently encompasses sponges in two genera: Oscarella with 17 described species and Pseudocorticium with one described species. Although sponges in this group are relatively well-studied, phylogenetic relationships among members of Oscarellidae and the validity of genus Pseudocorticium remain open questions. Here we present a phylogenetic analysis of Oscarellidae using four markers (18S rDNA, 28S rDNA, atp6, tatC), and argue that it should become a mono-generic family, with Pseudocorticium being synonymized with Oscarella, and with the transfer of Pseudocorticium jarrei to Oscarella jarrei. We show that the genus Oscarella can be subdivided into four clades, each of which is supported by either a small number of morphological characters or by molecular synapomorphies. In addition, we describe two new species of Oscarella from Norwegian fjords: O. bergenensis sp. nov. and O. nicolae sp. nov., and we compare their morphology, anatomy, and cytology with other species in this genus. Internal anatomical characters are similar in both species, but details of external morphology and particularly of cytological characters provide diagnostic features. Our study also confirms that O. lobularis and O. tuberculata are two distinct polychromic sibling species. This study highlights the difficulties of species identification in skeleton-less sponges and, more generally, in groups where morphological characters are scarce. Adopting a multi-marker approach is thus highly suitable for these groups.
Project description:Metacephalus Delong and Martinson, 1973 includes leafhopper species from Argentina, Bolivia, Brazil, Colombia, Ecuador (new record), Guyana, French Guiana (new record), Panama, Peru, and Venezuela. In the present revisionary study, we describe seven new species of Metacephalus, propose one species synonymy (M. cinctus as junior synonym of M. facetus), and provide new country records for species, considerably expanding knowledge about species distributions. The study also provides redescriptions and photographs of diagnostic characters for 12 previously described valid species and an identification key to all 21 species of Metacephalus. Molecular phylogenies of Metacephalus species are hypothesized based on maximum likelihood and Bayesian inference analyses of 1,387 bp of mitochondrial Cytochrome Oxidase I and 16S rDNA and nuclear histone H3. Results of the molecular phylogeny generated herein provided a base for understanding character homologies when presenting morphological diagnoses of Metacephalus species and exposed a high level of convergent characters in color pattern and male genitalia morphology usually used in morphological taxonomy of this group of leafhoppers.
Project description:Turris babylonia (Linnaeus, 1758) is the designated type species of Turris, the nominate genus of the family Turridae. This species has unusual taxonomic significance, since the family Turridae is a large biodiverse group that has been highly problematic in its taxonomy. In this article, we address the identity of Turris babylonia: molecular data presented here and expanded elsewhere demonstrate that two distinctive varieties with divergent shell morphology, both conventionally assigned to Turris babylonia, are in fact different species. We describe one of the forms as Turris assyria, new species. Thus, specimens previously assigned to Turris babylonia now comprise at least two taxa, Turris babylonia and Turris assyria; it remains possible that each is a multi-species complex. Some of the numerous varieties and morphologically divergent forms in each complex may prove not to be conspecific with the two species, each precisely defined in this work by a specific barcode sequence.