Mitochondrial Genes 16S Research Articles

Two new species of crayfish of the genus Cherax from Indonesian New Guinea (Crustacea, Decapoda, Parastacidae).

Two new species of the genus Cherax are described and illustrated. Cherax mosessalossa sp. n., endemic to the Klademak Creek drainage in Sorong, in the western part of the Kepala Burung (Vogelkop) peninsula, West Papua, Indonesia, is described, figured and compared with its closest relatives, Cherax misolicus Holthuis, 1949 and Cherax warsamsonicus. The new species may be easily distinguished from both by the shape of the rostrum, the shape of the chelae, the presence of five cervical spines, the shape of the scaphocerite, and short scattered hairs on the carapace. Cherax alyciae sp. n., endemic to creeks in the Digul River drainage in the eastern part of the Boven Digoel Regency, Papua, Indonesia, is described, figured, and compared with its closest relative, Cherax peknyi Lukhaup & Herbert, 2008. The new species may be easily distinguished from Cherax peknyi by the shape of the chelae, presence of a soft patch on the chelae of the males, and colouration. A molecular phylogeny based on two mitochondrial gene fragments, 16S and COI, supports the morphology-based description of the two new species, which can also be clearly distinguished by sequence differences.

Odontonia plurellicola sp. n. and Odontonia bagginsi sp. n., two new ascidian-associated shrimp from Ternate and Tidore, Indonesia, with a phylogenetic reconstruction of the genus (Crustacea, Decapoda, Palaemonidae).

Two new species of palaemonid shrimp associated with ascidian hosts, Odontonia bagginsi sp. n. from Tidore and Odontonia plurellicola sp. n., from Ternate, Indonesia are described and figured. Through phylogenetic analyses based on both morphological and molecular datasets (mitochondrial Cytochrome c oxidase subunit I gene and the 16S mitochondrial ribosomal gene) of the genus Odontonia, the phylogenetic positions of the new species have been reconstructed. Scanning Electron Microscopy has been used to observe additional characters on dactyli of the ambulatory pereiopods. Odontonia plurellicola sp. n. appears to be more closely related to O. simplicipes and O. seychellensis, but it differs most notably in the morphology of the rostrum and mouthparts. Odontonia plurellicola sp. n. appears to be the only Odontonia species living inside a phlebobranch ascidian Plurella sp. Odontonia bagginsi sp. n. is closely related to O. sibogae, but differs markedly in the abundance of setae on the propodi of the ambulatory pereiopods. In the present paper, O. maldivensis Fransen, 2006 is regarded as a junior synonym of O. rufopunctata Fransen, 2002 based on both morphological and molecular aspects.

Mitochondrial phylogeography and population structure of the cattle tick Rhipicephalus appendiculatus in the African Great Lakes region

BackgroundThe ixodid tick Rhipicephalus appendiculatus is the main vector of Theileria parva, wich causes the highly fatal cattle disease East Coast fever (ECF) in sub-Saharan Africa. Rhipicephalus appendiculatus populations differ in their ecology, diapause behaviour and vector competence. Thus, their expansion in new areas may change the genetic structure and consequently affect the vector-pathogen system and disease outcomes. In this study we investigated the genetic distribution of R. appendiculatus across agro-ecological zones (AEZs) in the African Great Lakes region to better understand the epidemiology of ECF and elucidate R. appendiculatus evolutionary history and biogeographical colonization in Africa.MethodsSequencing was performed on two mitochondrial genes (cox1 and 12S rRNA) of 218 ticks collected from cattle across six AEZs along an altitudinal gradient in the Democratic Republic of Congo, Rwanda, Burundi and Tanzania. Phylogenetic relationships between tick populations were determined and evolutionary population dynamics models were assessed by mismach distribution.ResultsPopulation genetic analysis yielded 22 cox1 and 9 12S haplotypes in a total of 209 and 126 nucleotide sequences, respectively. Phylogenetic algorithms grouped these haplotypes for both genes into two major clades (lineages A and B). We observed significant genetic variation segregating the two lineages and low structure among populations with high degree of migration. The observed high gene flow indicates population admixture between AEZs. However, reduced number of migrants was observed between lowlands and highlands. Mismatch analysis detected a signature of rapid demographic and range expansion of lineage A. The star-like pattern of isolated and published haplotypes indicates that the two lineages evolve independently and have been subjected to expansion across Africa.ConclusionsTwo sympatric R. appendiculatus lineages occur in the Great Lakes region. Lineage A, the most diverse and ubiquitous, has experienced rapid population growth and range expansion in all AEZs probably through cattle movement, whereas lineage B, the less abundant, has probably established a founder population from recent colonization events and its occurrence decreases with altitude. These two lineages are sympatric in central and eastern Africa and allopatric in southern Africa. The observed colonization pattern may strongly affect the transmission system and may explain ECF endemic instability in the tick distribution fringes.

Detection of Rickettsia spp. in ticks parasitizing toads (Rhinella marina) in the northern Brazilian Amazon.

This study evaluated rickettsial infection in ticks collected on toads from the northern Brazilian Amazon (Amapá state), where to our knowledge there are neither records of ticks from amphibians nor rickettsial infections in ticks. During 2016-2017, a total of 22 free-living toads were captured and identified as Rhinella marina. Overall, 12 (54.5%) toads were parasitized by a total of 97 ticks (6 males, 39 females, 31 nymphs, 21 larvae), giving a mean intensity of 8.1 ticks per infested toad. Two tick species were morphologically identified: Amblyomma rotundatum Koch (31 females, 14 nymphs), and Amblyomma dissimile Koch (6 males, 8 females, 17 nymphs). The 21 larvae were morphologically denoted as Amblyomma sp. Five toads were co-infested by A. rotundatum and A. dissimile. Morphological identifications were confirmed by nucleotide sequencing of fragments of the mitochondrial genes 16S rDNA, 12S rDNA and/or COX1. A total of 54 ticks were analyzed for the presence of rickettsial DNA. Eleven (9 females and 2 nymphs) out of 14 A. rotundatum ticks contained Rickettsia bellii. None of the 25 specimens of A. dissimile (6 males, 6 females, 13 nymphs) contained amplifiable rickettsial DNA. From 15 Amblyomma sp. larvae, a pool of 10 individuals contained Rickettsia sp. strain Colombianensi. Sequencing of the 16S rDNA amplicon derived from the positive pool yielded a sequence of A. dissimile. We detected Rickettsia sp. strain Colombianensi for the first time in Brazil. Prior records of this agent were restricted to Colombia and Honduras. In addition, we report the presence of A. rotundatum for the first time in the state of Amapá, where the only other record of A. dissimile was registered over 20years ago.

Revision of Sigaloeista Shea & Griffiths, 2010 (Helicarionidae: Gastropoda: Stylommatophora) from eastern Australia

ABSTRACTSigaloeista Shea & Griffiths, 2010 is a genus of small, litter-dwelling helicarionid snails that occurs in the rainforest and wet sclerophyll forest of northeastern New South Wales and southern Queensland. This group currently comprises three species known only from their shell morphology. We revise the taxonomy of this group using a comparison of key morphological features and mitochondrial genes COI and 16S, and describe four new species: Sigaloeista gracilis n. sp.; S. cavanbah n. sp.; S. dorrigo n. sp.; and S. ramula n. sp. Sigaloeista is unified by shared morphological characters including a small, glossy, discoidal shell of about 4.5 whorls, a body with a pronounced caudal horn and large, leaf-shaped shell lappets, and a reproductive system with a short vagina, absent epiphallic caecum, flagellum with internal cryptae and spermatophore with accessory spines.http://www.zoobank.org/urn:lsid:zoobank.org:pub:5D5D7603-06B2-4662-91BB-343E3BB5C4E8

Description, biology and molecular characterisation of Serpentirhabdias moi n. sp. (Nematoda: Rhabdiasidae) from Chironius exoletus (Serpentes: Colubridae) in Brazil

A new species of the genus Serpentirhabdias Tkach, Kuzmin et Snyder, 2014, S. moi n. sp., is described from a colubroid snake Chironius exoletus from Caxiuanã National Forest, State of Pará, Brazil. The species is characterised by having a triangular oral opening, absence of the buccal capsule, presence of six minute onchia in the oesophastome, and excretory glands of approximately the same length as the oesophagus. These qualitative morphological characters, as well as some measurements, differentiate the new species from other Neotropical and Nearctic Serpentirhabdias spp. The morphological description of parasitic adults of S. moi n. sp. is complemented by the description of free-living stages including males, females, and infective larvae. Comparative analysis of partial sequences of cox1 and 12S mitochondrial genes strongly supported the status of S. moi n. sp. as a new species. Molecular phylogeny based on sequences of the nuclear DNA region spanning the 3′ end of the 18S nuclear rRNA gene, ITS region (ITS1 + 5.8S + ITS2) and 5′ end of the 28S gene supported monophyly of all rhabdiasid genera included in the analysis and placed the new species into the Serpentirhabdias clade as sister taxon to S. fuscovenosa.

Phylogenetics and species delimitation of two hydrozoa (phylum Cnidaria): Turritopsis (McCrady, 1857) and Pennaria (Goldfuss, 1820)

Using a ~ 600 bps fragment of the mitochondrial 16S gene, we reconstruct the phylogenetic history of the species complex Pennaria disticha and of the genus Turritopsis. P. disticha and, within the genus Turritopsis, Turritopsis dohrnii are considered invasive species with a very broad geographical range. We show that the invasive T. dohrnii has reached the Gulf of Mexico (GoM) and Brazil. We heavily sampled the Bocas del Toro region, Panama, where three species of Turritopsis (the invasive T. dohrnii and the endemic T. sp. 1 and T. sp. 4) have been recorded, and found that the invasive T. dohrnii is the most common species, while the endemic species were either very rare (T. sp. 1) or were not found (T. sp. 4). We show that T. dohrnii from Bocas del Toro can revert its life cycle from medusa to polyp, while T. sp. 1 may lack this capability. Finally, we find that in the Maldives, Emirates, and the Red Sea, there are morphologically and genetically distinct Turritopsis lineages. With regard to Pennaria disticha, we analyzed new sequences from Thuwal (Saudi Arabia, Red Sea), Sint Eustatius (the Netherlands, Caribbean), Bocas del Toro (Panama, Caribbean Sea), Bergeggi (Italy, Mediterranean Sea), Tricase (Italy, Mediterranean Sea), Dibba Al-Fujairah (United Arab Emirates, Gulf of Oman), and Galveston (Texas, Gulf of Mexico). We confirm the presence of several clades and putative cryptic species that indicates multiple invasive episodes and undercover a new clade from the Gulf of Oman. Finally, species delimitation analyses recover 2 to 3 clades as separate species within P. disticha, and 7 to 9 species within Turritopsis, with T. lata being a complex of 2–4 cryptic species.

Phylogeny, evolution and mitochondrial gene order rearrangement in scale worms (Aphroditiformia, Annelida)

Next-generation sequencing (NGS) has become a powerful tool in phylogenetic and evolutionary studies. Here we applied NGS to recover two ribosomal RNA genes (18S and 28S) from 16 species and 15 mitochondrial genomes from 16 species of scale worms representing six families in the suborder Aphroditiformia (Phyllodocida, Annelida), a complex group of polychaetes characterized by the presence of dorsal elytra or scales. The phylogenetic relationship of the several groups of scale worms remains unresolved due to insufficient taxon sampling and low resolution of individual gene markers. Phylogenetic tree topology based on mitochondrial genomes is comparable with that based on concatenated sequences from two mitochondrial genes (cox1 and 16S) and two ribosomal genes (18S and 28S) genes, but has higher statistical support for several clades. Our analyses show that Aphroditiformia is monophyletic, indicating the presence of elytra is an apomorphic trait. Eulepethidae and Aphroditidae together form the sister group to all other families in this suborder, whereas Acoetidae is sister to Iphionidae. Polynoidae is monophyletic, but within this family the deep-sea subfamilies Branchinotogluminae and Macellicephalinae are paraphyletic. Mitochondrial genomes in most scale-worm families have a conserved gene order, but within Polynoidae there are two novel arrangement patterns in the deep-sea clade. Mitochondrial protein-coding genes in polynoids as a whole have evolved under strong purifying selection, but substitution rates in deep-sea species are much higher than those in shallow-water species, indicating that purifying selection is relaxed in deep-sea polynoids. There are positive selected amino acids for some mitochondrial genes of the deep-sea clade, indicating they may involve in the adaption of deep-sea polynoids. Overall, our study (1) provided more evidence for reconstruction of the phylogeny of Aphroditiformia, (2) provided evidence to refute the assumption that mitochondrial gene order in Errantia is conserved, and (3) indicated that the deep-sea extreme environment may have affected the mitochondrial genome evolution rate and gene order arrangement in Polynoidae.

First record of the Malaysian Bridle Snake, Dryocalamus subannulatus (Duméril, Bibron & Duméril, 1854), in Myanmar (Reptilia, Serpentes, Colubridae)

Dryocalamus subannulatus is reported for the first time from Myanmar. A single individual was found on the Thayawthadangyi Island Group in the Myeik Archipelago, Tanintharyi Region. Morphological features and a maximum likelihood analysis of the 16S mitochondrial gene confirm its identity. This specimen represents the first record of D. subannulatus north of the Isthmus of Kra.

Phylogeographic analysis reveals high genetic structure with uniform phenotypes in the paper wasp Protonectarina sylveirae (Hymenoptera: Vespidae).

Swarm-founding wasps are endemic and common representatives of neotropical fauna and compose an interesting social tribe of vespids, presenting both complex social characteristics and uncommon traits for a eusocial group, such as the absence of castes with distinct morphology. The paper wasp Protonectarina sylveirae (Saussure) presents a broad distribution from Brazil, Argentina and Paraguay, occurring widespread in the Atlantic rainforest and arboreal Caatinga, being absent in the Amazon region. Given the peculiar distribution among swarm-founding wasps, an integrative approach to reconstruct the evolutionary history of P. sylveirae in a spatial-temporal framework was performed to investigate: the presence of genetic structure and its relationship with the geography, the evolution of distinct morphologic lineages and the possible historical event(s) in Neotropical region, which could explain the observed phylogeographic pattern. Individuals of P. sylveirae were obtained from populations of 16 areas throughout its distribution for DNA extraction and amplification of mitochondrial genes 12S, 16S and COI. Analysis of genetic diversity, construction of haplotype net, analysis of population structure and dating analysis of divergence time were performed. A morphometric analysis was also performed using 8 measures of the body of the adult (workers) to test if there are morphological distinction among populations. Thirty-five haplotypes were identified, most of them exclusively of a group and a high population structure was found. The possibility of genetic divergence because of isolation by distance was rejected. Morphological analysis pointed to a great uniformity in phenotypes, with only a small degree of differentiation between populations of south and the remaining. Divergence time analysis showed a Middle/Late Miocene origin, a period where an extensive marine ingression occurred in South America. Divergence of haplogroups began from the Plio/Pleistocene boundary and the last glacial maximum most likely modeled the current distribution of species, even though it was not the cause of genetic breaks.

A new cryptic species of Asteronyx Müller and Troschel, 1842 (Echinodermata: Ophiuroidea), based on molecular phylogeny and morphology, from off Pacific Coast of Japan

The first phylogenetic and phylogeographic studies of the cosmopolitan deep-sea species, Asteronyx loveni Müller and Troschel, 1842, were conducted, based on specimens collected from off the Pacific coast of Japan. Partial sequences of mitochondrial 16S (68 specimens) and COI (24 specimens) genes were analyzed. Phylogenetic trees and network analyses revealed three lineages and five sub-lineages of A. loveni. Genetic distance and AMOVA (analysis of molecular variance) analyses suggested that the lineages should be considered three cryptic species. Skin on the aboral disc is partly thickened and forms a mesh-like pattern, which has never been reported in previous descriptions of Asteronyx; this is provided as a new taxonomic character. Based on absence/presence of mesh-like skin, one of the three lineages was assigned to A. loveni and another was described as Asteronyx reticulata new species. This new species can be distinguished from congeners by having mesh-like skin and small genital slits at the innermost position on the interradial oral disc.

Review of the leaf-litter skinks (Scincidae: Panaspis) from the Gulf of Guinea Oceanic Islands, with the description of a new species

ABSTRACTLeaf-litter skinks of the genus Panaspis are currently represented in the oceanic islands of the Gulf of Guinea by two species, Panaspis africana and P. annobonensis. Here we describe a third species, Panaspis thomensis sp. nov., endemic to São Tomé Island. Data from previous studies and a new phylogenetic analysis using the mitochondrial 16S gene shows that the new species is genetically divergent and reciprocally monophyletic with respect to P. africana. Morphological data (scalation and morphometry) identify consistent, yet subtle, phenotypic differences between the two island populations. We also confirm that P. annobonensis represents a valid species, sister to the species pair P. africana + P. thomensis sp. nov., based on both molecular and morphological evidence. This description raises the number of known Panaspis species in the Gulf of Guinea oceanic islands to three, with consequences for the interpretation of local endemicity.ZooBank—Panaspis thomensis:lsid: zoobank.org:act:A1E69D28-CF4C-4070-BBCC-91E39C21DBA6

A New Bromeligenous Species of Fritziana Mello-Leitão, 1937 (Amphibia: Anura: Hemiphractidae) from High Elevations in the Serra Dos Órgãos, Rio de Janeiro, Brazil

Abstract Fritziana is a genus of phytotelm-dwelling frogs that inhabits bamboo and bromeliads in the southern and southeastern portions of the Brazilian Atlantic Forest. Currently, five species are known, but the existence of undescribed species has been acknowledged. Here, we conducted a species-delimitation analysis of Fritziana using deoxyribonucleic acid sequences comprising two fragments of a mitochondrial gene (16S). The species delimitation analysis (with 16S) with Bayesian inference and maximum parsimony supported the recognition of a new species as an exclusive lineage, sister to all other Fritziana species. Bioacoustic and morphological evidence also support this finding. The new species occurs from 1166 to 2146 m above sea level and inhabits bromeliads from the National Park of Serra dos Orgaos, in the municipality of Teresopolis, state of Rio de Janeiro, Brazil. Compared with its congeners, the new species has nostrils narrowly separated, diameter of tympanum equal to or larger than diameter o...

Rediscovery of Rhacophorus yaoshanensis and Theloderma kwangsiensisat their type localities after five decades.

Rhacophorus yaoshanensis Liu Hu, 1962 and Theloderma kwangsiensis Liu Hu, 1962 were described by Liu Hu (1962) based on two specimens and one specimen, respectively, from the Dayaoshan Ranges, Guangxi, China. Since these two species were described, no additional specimens have been collected from their type localities, presenting an issue for phylogenetic studies of the genera. Five decades later, we have rediscovered R. yaoshanensis and T. kwangsiensis from their type localities. In this paper, we re-describe the two species and conduct a preliminary assessment of their phylogenetic relationships using two mitochondrial DNA genes (12S and 16S rRNA). The results indicate with high support that R. yaoshanensis is closely related to Rhacophorus pinglongensis. Theloderma kwangsiensis is nested within Theloderma corticale, with only 0.0-0.6% pairwise divergence, a level typical of intraspecific variation. Based on both molecular and morphological analyses, we further confirm that T. kwangsiensis is a synonym of T. corticale. Shiwandashan National Nature Reserve, Guangxi Province, China, is a new record for T. corticale.

Molecular data confirm the taxonomic position of Hymenolepis erinacei (Cyclophyllidea: Hymenolepididae) and host switching, with notes on cestodes of Palaearctic hedgehogs (Erinaceidae).

The cestode Hymenolepis erinacei is regarded as a widely distributed parasite in European hedgehogs of the genus Erinaceus, although the taxonomic position of this hymenolepidid has been debated for a considerable period of time. We present the first molecular data for this cestode, including partial DNA sequences of mitochondrial 16S and nuclear 28S ribosomal genes. Molecular phylogenetic analysis clusters H. erinacei in one clade together with representatives of the genus Hymenolepis from rodents. Characteristic morphological features, including the oval embryophore without filaments and shape of the embryonic hooks of H. erinacei are described. Features of these cestode eggs are proposed as a basis for non-invasive detection of parasitic infections in small mammal populations. The present study explores phylogenetic relationships within the genus Hymenolepis and the host switching related to H. erinacei. Cases of host switching in other genera of the family Hymenolepididae are reviewed. A short critical review of cestodes parasitizing hedgehogs in the Palaearctic is presented.

Species limits within the widespread Amazonian treefrog Dendropsophus parviceps with descriptions of two new species (Anura, Hylidae).

The genus Dendropsophus is one of the most speciose among Neotropical anurans and its number of described species is increasing. Herein, molecular, morphological, and bioacoustic evidence are combined to assess species limits within D. parviceps, a widely distributed species in the Amazon Basin. Phylogenetic relationships were assessed using 3040 bp sequences of mitochondrial DNA, genes 12S, ND1, and CO1. The phylogeny shows three well-supported clades. Bioacoustic and morphological divergence is congruent with those clades demonstrating that Dendropsophus parviceps is a species complex. Dendropsophus parviceps sensu stricto occurs in the Amazon basin of Ecuador, northern Peru, southern Colombia and northwestern Brazil. It is sister to two previously undescribed species, D. kubricki sp. n. from central Peru and D. kamagarini sp. n. from southern Peru, northeastern Bolivia, and northwestern Brazil. Genetic distances (uncorrected p, gene 12S) between D. parviceps and the new species is 3 to 4%. Dendropsophus kamagarini sp. n. can be distinguished from D. parviceps by having a prominent conical tubercle on the distal edge of the upper eyelid (tubercle absent in D. parviceps). Dendropsophus kubricki sp. n. differs from D. parviceps by having scattered low tubercles on the upper eyelids (smooth in D. parviceps). Dendropsophus parviceps and both new species differ from all their congeners by their small size (adult maximum SVL = 28.39 mm in females, 22.73 mm in males) and by having a bright orange blotch on the hidden areas of the shanks and under arms. The advertisement call of the two new species has lower dominant frequency relative to D. parviceps. Probable speciation modes are discussed. Available evidence indicates that ecological speciation along an elevation gradient is unlikely in this species complex.

Morphological and molecular characterization of Onchocerca fasciata (Nematoda, Onchocercidae) from dromedary camels (Camelus dromedarius) in Iran.

Skin nodules of Onchocerca fasciata Railliet and Henry, 1910 (Spirurida, Onchocercidae) are a common finding in dromedary camels, though with a minimal clinical impact. There is little information about the morphology, molecular make-up and pathological impact of this parasite. Onchocerca fasciata nodules (1.3–2.1 cm in diameter and 509–841 mg in weight) were detected on the neck region in 31.5% of dromedary camels examined in Kerman province, southeastern Iran. Of 38 isolated nodules, only 23 (60.5%) contained viable worms. Measurement and morphological analyses were performed on isolated female worms by light microscopy. The identification of O. fasciata specimens was confirmed by sequence analysis of two mitochondrial genes (12S rDNA and cox1), which showed 0.4% divergence from available O. fasciata sequences. In addition, a phylogeny of filarial nematodes was constructed, based on these two mitochondrial genes and five nuclear genes (18S rDNA, 28S rDNA, MyoHC, rbp1, hsp70); this indicated that O. fasciata belongs to clade ONC3 of Onchocercidae, with representatives of the genera Onchocerca and Dirofilaria. Within the genus Onchocerca, O. fasciata is grouped with bovine parasitic species and the human parasitic Onchocerca volvulus, which suggests an impact of domestication on the radiation of the genus. Data provided here on the distribution and morphology of O. fasciata contribute to the molecular identification and phylogenetic position of the species.

Systematics and phylogeography of the Australasian mangrove crabs Parasesarma semperi and P. longicristatum (Decapoda : Brachyura : Sesarmidae) based on morphological and molecular data

Parasesarma semperi (Bürger, 1893) was first described from Bohol in the Philippines and is considered to be widely distributed in Southeast Asia. Parasesarma longicristatum (Campbell, 1967) was originally described as a subspecies of P. semperi from Queensland, Australia, and later recognised as a full species. In this study, we re-examine specimens of the two species from across their entire geographic range using genetic markers, a morphometric analysis, and traditional morphological characters. Previous taxonomic species diagnoses were found to be unreliable, but morphometric principle component analyses consistently separate the two species, with the length to width ratio of the propodus of the fourth pereiopod being of particular importance. Genetic data corresponding to the mitochondrial genes COI, ND1 and 16S confirmed a close sister relationship between the two species, forming reciprocally monophyletic groups. Both species have high haplotype diversities and high intraspecific gene flow.

Strong genetic subdivision in Leptobrachium hendricksoni (Anura: Megophryidae) in Southeast Asia

Many biodiversity hotspots are located in areas with a complex geological history, like Southeast Asia, where species diversity may still be far underestimated, especially in morphologically conservative groups like amphibians. Recent phylogenetic studies on the frog genus Leptobrachium from Southeast Asia revealed the presence of deeply divergent mitochondrial clades in Leptobrachium hendricksoni from Malaysia and Sumatra but populations from Thailand have not been studied so far. In this study, we re-evaluate patterns of intraspecific genetic diversity in L. hendricksoni based on the analysis of combined sequences of mitochondrial 12S and 16S genes (1310 base pairs) including for the first time samples from southern Thailand. Thai populations of L. hendricksoni formed a distinct clade with respect to populations from central and southern Malaysia and Sumatra. High sequence divergence between lineages from Thailand, Malaysia and Sumatra suggests the possible presence of cryptic species in L. hendricksoni. Divergence within L. hendricksoni dates back to the late Miocene, around 6 Mya, when lineages from Thailand, north Malaysia and Sumatra split from a lineage in south Malaysia, at about the same time as rising sea levels isolated the Thai-Malay peninsula. Subsequent splits took place later in the Pliocene, around 4.5 and 2.6 Mya. Our results highlight the role of geological history in promoting population divergence and speciation.

Position of enigmatic miniature trichomycterid catfishes inferred from molecular data (Siluriformes)

Trichomycteridae is a well‐corroborated catfish family that comprises about 300 valid species distributed in eight subfamilies. The phyletic status of the Trichomycterinae is uncertain, with different hypothesis regarding the position of the miniaturized Trichomycterus hasemani group. This group comprises four valid species, and neither its monophyly nor its positioning among the Trichomycteridae was tested in a phylogenetic framework. Bayesian Inference and Maximum Likelihood analyses of a molecular data set comprising the mitochondrial genes 12S and 16S and the nuclear genes H3, MYH6 and RAG2 (2983 bp) for 26 taxa highly supported the miniature catfish T. hasemani group as monophyletic and sister to the Tridentinae, consequently recognized as a new genus of this subfamily. Potamoglanis gen. nov. is diagnosed by seven character states: an angle of 35–40° between the main longitudinal axis of the head and the main axis of the autopalatine; thin tubular shape of the second ceratobranchial; presence of six or seven anal‐fin rays; eyes dorsally placed on head; opercular and interopercular odontodes patches not juxtaposed; absence of a distal process on the hyomandibula and presence of a long process on the anterior region of the hyomandibula. Potamoglanis gen. nov is similar to the Tridentinae genera by the presence of a wide cranial fontanelle; presence of a short ventral process in the opercular bone and by the origin of the dorsal fin placed in a vertical through the anal‐fin origin.