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https://www.readbyqxmd.com/read/29298317/the-first-record-of-albanerpetontid-amphibians-amphibia-albanerpetontidae-from-east-asia
#1
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
https://www.readbyqxmd.com/read/29297167/health-status-of-pelophylax-ridibundus-amphibia-ranidae-in-a-rice-paddy-ecosystem-in-southern-bulgaria-and-its-importance-in-assessing-environmental-state-haematological-parameters
#2
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
https://www.readbyqxmd.com/read/29247588/oocyte-maturation-in-the-toad-rhinella-arenarum-amphibia-anura-evidence-of-camp-involvement-in-steroid-production-and-action
#3
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
https://www.readbyqxmd.com/read/29245736/rediscovery-of-the-endangered-frog-i-phrynopus-i-i-montium-i-shreve-1938-amphibia-anura-craugastoridae-in-the-cloud-forest-of-central-peru
#4
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
https://www.readbyqxmd.com/read/29245621/the-vietnamese-population-of-i-megophrys-i-i-kuatunensis-i-amphibia-megophryidae-represents-a-new-species-of-asian-horned-frog-from-vietnam-and-southern-china
#5
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
https://www.readbyqxmd.com/read/29241181/sex-determination-and-sex-chromosomes-in-amphibia
#6
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
https://www.readbyqxmd.com/read/29239487/evolution-of-skull-shape-in-the-family-salamandridae-amphibia-caudata
#7
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
https://www.readbyqxmd.com/read/29219040/taxonomic-relationships-of-hynobius-stejnegeri-and-h-yatsui-with-description-of-the-amber-colored-salamander-from-kyushu-japan-amphibia-caudata
#8
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
https://www.readbyqxmd.com/read/29210016/amphibiophilus-mooiensis-n-sp-nematoda-amphibiophilidae-a-parasite-of-amietia-delalandii-dum%C3%A3-ril-bibron-amphibia-pyxicephalidae-from-south-africa
#9
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...
December 5, 2017: Systematic Parasitology
https://www.readbyqxmd.com/read/29205342/phylogenetic-analyses-of-the-hepatic-architecture-in-vertebrates
#10
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...
December 4, 2017: Journal of Anatomy
https://www.readbyqxmd.com/read/29187793/a-new-species-of-phrynopus-amphibia-anura-craugastoridae-from-upper-montane-forests-and-high-andean-grasslands-of-the-pui-pui-protected-forest-in-central-peru
#11
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 intisp. 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
https://www.readbyqxmd.com/read/29091121/choledocystus-elegans-digenea-plagiorchiidae-of-leptodactylus-paraensis-amphibia-leptodactylidae-from-the-brazilian-amazon
#12
Tássia Fernanda Furo Gomes, Francisco Tiago de Vasconcelos Melo, Elane Guerreiro Giese, Adriano Penha Furtado, Jeannie Nascimento Dos Santos
The trematodes are parasites of the several vertebrates including amphibians, however the knowledge about of the taxonomy these parasites is still confuse. The trematode Choledocystus elegans was found in the small intestine of the Leptodactylus paraensis in eastern Amazon and presents the following characteristics: several pointed tegumentary spines, papillae on the outer and inner edges of the oral and ventral suckers, a round, well-developed cirrus sac, a well-developed cirrus, oblique testicles, a ovary right side, uterine loops extending between the testicles, follicular vitellaria distributed throughout the body, starting at the genital pore region and caeca close the end of the body...
October 30, 2017: Revista Brasileira de Parasitologia Veterinária, Brazilian Journal of Veterinary Parasitology
https://www.readbyqxmd.com/read/29089838/bryophryne-phuyuhampatu-sp-n-a-new-species-of-cusco-andes-frog-from-the-cloud-forest-of-the-eastern-slopes-of-the-peruvian-andes-amphibia-anura-craugastoridae
#13
Alessandro Catenazzi, Alex Ttito, M Isabel Diaz, Alexander Shepack
A new species of Bryophryne from the humid montane forest of the Department of Cusco, Peru, is described. Specimens were collected at 2795-2850 m a.s.l. in the Área de Conservación Privada Ukumari Llaqta, Quispillomayo valley, in the province of Paucartambo. The new species is readily distinguished from all other species of Bryophryne by having green coloration on dorsum, and blue flecks on flanks and ventral parts. Specimens are characterized by lacking a distinct tympanic annulus, tympanic membrane, and dentigerous processes of vomers, and by having dorsal skin shagreen, discontinuous dorsolateral folds, skin tuberculate on flanks, skin areolate on ventral surfaces of the body, and fingers and toes without lateral fringes or webbing...
2017: ZooKeys
https://www.readbyqxmd.com/read/29059674/chromosome-banding-in-amphibia-xxxv-highly-mobile-nucleolus-organizing-regions-in-craugastor-fitzingeri-anura-craugastoridae
#14
Michael Schmid, Claus Steinlein, Wolfgang Feichtinger, Indrajit Nanda
A 7-year cytogenetic study on the leaf litter frog Craugastor fitzingeri from Costa Rica and Panama revealed the existence of highly mobile nucleolus organizing regions (NORs) in their genomes. Silver (Ag)-staining of the active NORs demonstrated an exceptional interindividual pattern of NOR distribution at the telomeres of the chromosomes. All individuals examined showed a different and specific NOR location in their karyotypes. Furthermore, intraindividual variation in the NOR sites was found. This observation suggested the existence of mobile NORs in C...
October 24, 2017: Cytogenetic and Genome Research
https://www.readbyqxmd.com/read/29020573/new-species-of-talaromyces-isolated-from-maize-indoor-air-and-other-substrates
#15
Stephen W Peterson, Željko Jurjević
Talaromyces strains isolated from maize seeds and the built environment were examined taxonomically because they could not be identified as previously described species. Using phenotypic analysis, DNA sequencing, and phylogenetic and concordance analyses, the authors discovered and described 10 new species in sect. Islandici and 1 new species in sect. Subinflati. Taxonomic novelties in sect. Islandici are Talaromyces delawarensis, T. herodensis, T. juglandicola, T. kilbournensis, T. novojersensis, T. ricevillensis, T...
September 18, 2017: Mycologia
https://www.readbyqxmd.com/read/28940082/applicability-and-efficacy-of-diatom-indices-in-water-quality-evaluation-of-the-chambal-river-in-central-india
#16
Prateek Srivastava, Sarika Grover, Jyoti Verma, Ambrina Sardar Khan
Diatom indices have gained considerable popularity in estimation of the trophic state and degree of pollution in lotic ecosystems. However, their applicability and efficacy have rarely been tested in Indian streams and rivers. In the present study, benthic diatom assemblages were sampled at 27 sites along the Chambal River in Central India. PCA revealed three groups of sites, namely, heavily polluted (HVPL), moderately polluted (MDPL), and least polluted (SANT). A total of 100 diatom taxa belonging to 40 genera were identified...
September 23, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28911821/on-the-occurrence-and-enigmatic-functions-of-mixed-chemical-plus-electrical-synapses-in-the-mammalian-cns
#17
REVIEW
James I Nagy, Alberto E Pereda, John E Rash
Electrical synapses with diverse configurations and functions occur at a variety of interneuronal appositions, thereby significantly expanding the physiological complexity of neuronal circuitry over that provided solely by chemical synapses. Gap junctions between apposed dendritic and somatic plasma membranes form "purely electrical" synapses that allow for electrical communication between coupled neurons. In addition, gap junctions at axon terminals synapsing on dendrites and somata allow for "mixed" (dual chemical+electrical) synaptic transmission...
September 11, 2017: Neuroscience Letters
https://www.readbyqxmd.com/read/28905992/the-vertebrate-heart-an-evolutionary-perspective
#18
REVIEW
Andrea Stephenson, Justin W Adams, Mauro Vaccarezza
Convergence is the tendency of independent species to evolve similarly when subjected to the same environmental conditions. The primitive blueprint for the circulatory system emerged around 700-600 Mya and exhibits diverse physiological adaptations across the radiations of vertebrates (Subphylum Vertebrata, Phylum Chordata). It has evolved from the early chordate circulatory system with a single layered tube in the tunicate (Subphylum Urchordata) or an amphioxus (Subphylum Cephalochordata), to a vertebrate circulatory system with a two-chambered heart made up of one atrium and one ventricle in gnathostome fish (Infraphylum Gnathostomata), to a system with a three-chambered heart made up of two atria which maybe partially divided or completely separated in amphibian tetrapods (Class Amphibia)...
December 2017: Journal of Anatomy
https://www.readbyqxmd.com/read/28794672/a-new-species-of-terrestrial-breeding-frog-amphibia-craugastoridae-pristimantis-from-high-elevations-of-the-pui-pui-protected-forest-in-central-peru
#19
Edgar Lehr, Rudolf von May
We describe a new species of Pristimantis from upper montane forests and high Andean grasslands of the Pui Pui Protected Forest and its close surroundings, Región Junín, central Peru. The description of the new species is based on 34 specimens found at elevations between 3400 and 3936 m a.s.l. Pristimantis attenboroughisp. n. is characterized by a snout-vent length of 14.6-19.2 mm in adult males (n = 21), 19.2-23.0 mm in adult females (n = 10), and is compared morphologically and genetically with other taxonomically and biogeographically relevant species of Pristimantis...
2017: ZooKeys
https://www.readbyqxmd.com/read/28769692/the-advertisement-call-and-comments-on-the-distribution-of-eleutherodactylus-bilineatus-bokermann-1975-an-endemic-frog-of-bahia-state-brazil-amphibia-anura
#20
Iuri Ribeiro Dias, Caio Vinicius de Mira-Mendes, Carlos Augusto Souza-Costa, Flora Acuña Juncá, Mirco Solé
Advertisement calls can be used to aid solving taxonomic problems and understanding the evolution of certain groups. In this study, the advertisement call of Eleutherodactylus bilineatus is described. It is composed by two different notes with a total duration of 0.529-4.241 seconds and dominant frequency of 1.72-3.45 kHz. Additionally, new data is provided on the geographical distribution of Eleutherodactylus bilineatus and the most inland record for this species.
2017: ZooKeys
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