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Michael Schmid, Claus Steinlein
A detailed cytogenetic study on the leaf litter frog Eleutherodactylus johnstonei from 14 different Caribbean islands and the mainlands of Venezuela and Guyana revealed the existence of multimorphic XY♂/XX♀ sex chromosomes 14. Their male sex determination and development depends either on the presence of 2 telocentric chromosomes 14 (XtYt), or on 1 submetacentric chromosome 14 (Xsm) plus 1 telocentric chromosome 14 (Yt), or on the presence of 2 submetacentric chromosomes 14 (XsmYsm). The female sex determination and development requires either the presence of 2 telocentric chromosomes 14 (XtXt) or 2 submetacentric chromosomes 14 (XsmXsm)...
March 16, 2018: Cytogenetic and Genome Research
Jennifer A Sheridan, Bryan L Stuart
Accurately delimiting species and their geographic ranges is imperative for conservation, especially in areas experiencing rapid habitat loss. Southeast Asia currently has one of the highest rates of deforestation in the world, is home to multiple biodiversity hotspots, and the majority of its countries have developing economies with limited resources for biodiversity conservation. Thus, accurately delimiting species and their ranges is particularly important in this region. We examined genetic and morphological variation in the widespread frog species Sylvirana nigrovittata (and its long-treated junior synonym S...
2018: PloS One
Alessandro Catenazzi, Alex Ttito
We describe a new species of small strabomantid frog (genus Psychrophrynella ) from a humid montane forest in the Peruvian Department of Puno. Specimens were collected at 2,225 m a.s.l. in the leaf litter of primary montane forest near Thiuni, along the Macusani-San Gabán road, in the province of Carabaya. The new species is assigned to Psychrophrynella on the basis of morphological similarity, including presence of a tubercle on the inner edge of the tarsus, and call composed of multiple notes. We also include genetic distances for 16S rRNA partial sequences between the new species and other strabomantid frogs...
2018: PeerJ
Chatmongkon Suwannapoom, Montri Sumontha, Jitthep Tunprasert, Thiti Ruangsuwan, Parinya Pawangkhanant, Dmitriy V Korost, Nikolay A Poyarkov
We report on a discovery of Siamophryne troglodytes Gen. et sp. nov., a new troglophilous genus and species of microhylid frog from a limestone cave in the tropical forests of western Thailand. To assess its phylogenetic relationships we studied the 12S rRNA-16S rRNA mtDNA fragment with final alignment comprising up to 2,591 bp for 56 microhylid species. Morphological characterization of the new genus is based on examination of external morphology and analysis of osteological characteristics using microCT-scanning...
2018: PeerJ
Juan M Ferro, Dario E Cardozo, Pablo Suárez, Juan M Boeris, Ailin Blasco-Zúñiga, Gastón Barbero, Anderson Gomes, Thiago Gazoni, William Costa, Cleusa Y Nagamachi, Miryan Rivera, Patricia P Parise-Maltempi, John E Wiley, Julio C Pieczarka, Celio F B Haddad, Julián Faivovich, Diego Baldo
The hylid tribe Cophomantini is a diverse clade of Neotropical treefrogs composed of the genera Aplastodiscus, Boana, Bokermannohyla, Hyloscirtus, and Myersiohyla. The phylogenetic relationships of Cophomantini have been comprehensively reviewed in the literature, providing a suitable framework for the study of chromosome evolution. Employing different banding techniques, we studied the chromosomes of 25 species of Boana and 3 of Hyloscirtus; thus providing, for the first time, data for Hyloscirtus and for 15 species of Boana...
2018: PloS One
David Bruce Conn, Zdzisław Świderski, Jordi Miquel
Despite their tremendous diversity and their medical and veterinary importance, details of egg ultrastructure among the digenean trematodes has been studied rather little. The available literature is spread over several decades and several species, but has not been adequately reviewed to reveal patterns of similarity and divergence. We present this review to synthesize and analyse what is known from the available literature reporting studies using both transmission electron microscopy (TEM) and scanning electron microscopy (SEM)...
March 26, 2018: Acta Parasitologica
Roman Svitin, Yuriy Kuzmin, Louis du Preez
Rhabdias picardiae previously known from the Guttural Toad, Sclerophrys gutturalis (Bufonidae) is described from a new host, Delaland's River Frog, Amietia delalandii (Pyxicephalidae). The species identification is confirmed by analysis of the COI gene sequence and morphological comparison with the original description. Morphological details of apical structures in adult parasitic R. picardiae, namely, the shape and position of lips, the number and position of external labial papillae, and the buccal capsule morphology are described using light and scanning electron microscopy...
March 26, 2018: Acta Parasitologica
Hui-Xia Chen, Kuang Zhang, Lu-Ping Zhang, Liang Li
Seuratascaris numidica (Seurat, 1917) is a specialized nematode species parasitizing amphibians only. In the present study, the detailed morphology of this poorly known species was studied using light and scanning electron microscopy based on the newly material collected from Hoplobatrachus chinensis (Osbeck) (Amphibia: Anura) in China. We found that the relative length of intestinal caecum in our male specimens (representing 68.4-71.1% of oesophageal length) is slighter longer than the previously reported data (not over 60...
March 26, 2018: Acta Parasitologica
Pallab Maity, Anjum N Rizvi, Charles R Bursey
Rhabdias stomatica sp. nov. from the lungs of Duttaphrynus stomaticus (Lutken, 1864) from Dehradun, Uttarakhand, India is described and illustrated. Rhabdias stomatica sp. nov. is the 16th species described from the Oriental biogeographical region and the 8th species from India. The new species is differentiated from the closely related Oriental species in having 4 weakly developed lips, a trapezoidal shaped buccal cavity, different position of nerve ring and in the esophagus/body length ratio. In addition, to the new species found in the lungs, mature specimens of Aplectana macintoshii (Stewart, 1914) Travassos, 1931 and larvae representing two unidentified species of nematode were found in the large intestine of the D...
March 26, 2018: Acta Parasitologica
Ryoko Matsumoto, Susan E Evans
Albanerpetontids are an enigmatic fossil amphibian group known from deposits of Middle Jurassic to Pliocene age. The oldest and youngest records are from Europe, but the group appeared in North America in the late Early Cretaceous and radiated there during the Late Cretaceous. Until now, the Asian record has been limited to fragmentary specimens from the Late Cretaceous of Uzbekistan. This led to speculation that albanerpetontids migrated into eastern Asia from North America in the Albian to Cenomanian interval via the Beringian land bridge...
2018: PloS One
Zhivko Zhelev, Stefan Tsonev, Katerina Georgieva, Desislava Arnaudova
Pollution effects on haematological parameters in Pelophylax ridibundus individuals were investigated; animals were collected from two sites in Southern Bulgaria: the Tsalapitsa rice fields (RF) and the Vacha river (reference site, RS). Blood analysis showed significant differences between the haematological parameters of RBC, WBC, Hb, packed cell volume (PCV) and frogs' leucogram from RF and those from RS. These findings provide information on long-term background pollution of the habitat (RF) under investigation...
January 3, 2018: Environmental Science and Pollution Research International
Ana Josefina AriasTorres, José Bernardino Páez, Liliana Isabel Zelarayán
In this work, we describe the participation of the Adenylate cyclase/3'-5'-cyclic adenonsine monophosphate (cAMP) pathway in the seasonal follicular secretion of progesterone (P4 ) and testosterone (T), and its relationship with the maturation of Rhinella arenarum oocytes. Under gonadotropin stimulation, P4 secretion was the dominant steroid produced during the reproductive period, resulting in 100% germinal vesicle breakdown (GVBD) in oocytes in vitro; in contrast, T and estradiol (E2 ) secretion increased (∼16 nM/20 follicles and ∼80 pM/20 follicles, respectively) during the non-reproductive period, but only yielded 50% GVBD...
December 16, 2017: Molecular Reproduction and Development
Rudolf VON May
Phrynopus montium (Shreve, 1938) was described from Cascas, Junín Department, Peru, at an undetermined elevation between 3000 and 4000 m a.s.l. in the Cordillera Central. With the exception of the type specimens used in the original description, no additional sightings of P. montium had been reported for 76 years. Additionally, its coloration in life, microhabitat use, and precise elevational distribution remained unknown. During a field expedition conducted in 2014, two individuals of P. montium were found at an upper cloud forest site in central Peru, 8...
October 24, 2017: Zootaxa
Benjamin Tapley, Timothy Cutajar, Stephen Mahony, Chung Thanh Nguyen, Vinh Quang Dau, Tao Thien Nguyen, Hao VAN Luong, Jodi J L Rowley
The Asian frog genus Megophrys is a diverse group of morphologically conserved, forest-dwelling frogs. The genus harbours highly localised species diversification and new species continue to be described on a regular basis. We examined the taxonomic status of a population of Megophrys frogs from the Hoang Lien Range in northern Vietnam and southern China previously identified as M. kuatunensis (subgenus Panophrys). Preliminary phylogenetic analyses using a fragment of 16S rDNA places the species in question within the Megophrys (subgenus Panophrys) species group, a primarily Chinese radiation within the genus...
November 8, 2017: Zootaxa
Ikuo Miura
Sex chromosomes in most amphibians are homomorphic (undifferentiated) in both sexes and are characterized by frequent turnover. This is in sharp contrast to sex chromosomes in 2 major vertebrate groups, the mammals and birds, where they are heteromorphic in one sex and are highly conserved. Sex-determining mechanisms in anuran amphibians, particularly in relation to the turnover of sex-determining genes and sex chromosomes, are summarized and their evolution is discussed.
December 15, 2017: Sexual Development: Genetics, Molecular Biology, Evolution, Endocrinology, Embryology, and Pathology of Sex Determination and Differentiation
Ana Ivanović, Jan W Arntzen
We carried out a comparative morphometric analysis of 56 species of salamandrid salamanders, representing 19 out of 21 extant genera, with the aim of uncovering the major patterns of skull shape diversification, and revealing possible trends and directions of evolutionary change. To do this we used micro-computed tomography scanning and three-dimensional geometric morphometrics, along with a well-resolved molecular phylogeny. We found that allometry explains a relatively small amount of shape variation across taxa...
December 14, 2017: Journal of Anatomy
Masafumi Matsui, Kanto Nishikawa, Atsushi Tominaga
Examination of the holotype of Hynobius stejnegeri Dunn, 1923 revealed that the species is identical with H. yatsui Oyama, 1947 , recently resurrected from H. naevius (Temminck and Schlegel, 1838). The name H. yatsui is therefore relegated to a subjective junior synonym of H. stejnegeri. The latter name, however, has been widely applied to an amber-colored or tortoise-shell salamander from Kyushu, southwestern Japan, which now requires a new name. We, thus, describe the ambercolored salamander as a new species Hynobius ikioi...
December 2017: Zoological Science
Roman Svitin, Louis Du Preez
Four species of the genus Amphibiophilus Skrjabin, 1916 from pyxycephalid frogs in southern and central Africa are currently recognised as valid. Several specimens of Amphibiophilus were found in material from the common river frog, Amietia delalandii (Duméril & Bibron) (Amphibia: Pyxicephalidae), collected in Potchefstroom (North-West Province, South Africa). These specimens clearly differ from all previously known species by the shape of the distal end of the spicule, the shape of the gubernaculum and the structure of the synlophe...
January 2018: Systematic Parasitology
Nobuyoshi Shiojiri, Harunobu Kametani, Noriaki Ota, Yusuke Akai, Tomokazu Fukuchi, Tomoka Abo, Sho Tanaka, Junri Sekiguchi, Sachie Matsubara, Hayato Kawakami
The mammalian liver has a structural and functional unit called the liver lobule, in the periphery of which the portal triad consisting of the portal vein, bile duct and hepatic artery is developed. This type of hepatic architecture is detectable in many other vertebrates, including amphibians and birds, whereas intrahepatic bile ducts run independently of portal vein distribution in actinopterygians such as the salmon and tilapia. It remains to be clarified how the hepatic architectures are phylogenetically developed among vertebrates...
February 2018: Journal of Anatomy
Edgar Lehr, Rudolf von May, Jiří Moravec, Juan Carlos Cusi
We describe a new species of Phrynopus from the upper montane forests and high Andean grasslands (puna) of the Pui Pui Protected Forest and its close surroundings (Región Junín, central Peru) and compare it morphologically and genetically with other species of Phrynopus . Phrynopus inti sp. n. is known from four localities outside and two localities inside the Pui Pui Protected Forest between 3350 and 3890 m a.s.l. Studied specimens of the new species are characterized by a snout-vent length of 27.2-35.2 mm in males (n = 6), and 40...
2017: ZooKeys
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