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  1 / 706 MEDLINE  
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PMID:29381753
Autor:Sprague TA; Bateman HL
Endereço:College of Integrative Sciences and Arts, Arizona State University, Mesa, Arizona, United States of America.
Título:Influence of seasonality and gestation on habitat selection by northern Mexican gartersnakes (Thamnophis eques megalops).
Fonte:PLoS One; 13(1):e0191829, 2018.
ISSN:1932-6203
País de publicação:United States
Idioma:eng
Resumo:Species conservation requires a thorough understanding of habitat requirements. The northern Mexican gartersnake (Thamnophis eques megalops) was listed as threatened under the U.S. Endangered Species Act in 2014. Natural resource managers are interested in understanding the ecology of this subspecies to guide management decisions and to determine what features are necessary for habitat creation and restoration. Our objective was to identify habitat selection of northern Mexican gartersnakes in a highly managed, constructed wetland hatchery. We deployed transmitters on 42 individual gartersnakes and documented use of habitat types and selection of specific habitat features. Habitat selection was similar between males and females and varied seasonally. During the active season (March-October), gartersnakes primarily selected wetland edge habitat with abundant cover. Gestating females selected similar locations but with less dense cover. During the inactive season (November-February), gartersnakes selected upland habitats, including rocky slopes with abundant vegetation. These results of this study can help inform management of the subspecies, particularly in human-influenced habitats. Conservation of this subspecies should incorporate a landscape-level approach that includes abundant wetland edge habitat with a mosaic of dense cover for protection and sparsely vegetated areas for basking connected to terrestrial uplands for overwintering.
Tipo de publicação: JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T


  2 / 706 MEDLINE  
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PMID:29181900
Autor:Ren JL; Wang K; Jiang K; Guo P; Li JT
Endereço:CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu Sichuan 610041, China.
Título:A new species of the Southeast Asian genus (Serpentes: Colubridae: Natricinae) from western Hunan, China.
Fonte:Zool Res; 38(5):251-263, 2017 Sep 18.
ISSN:2095-8137
País de publicação:China
Idioma:eng
Resumo:A new species of natricine snake of the Southeast Asian genus Gü nther, 1872 is described from western Hunan Province of China based on both mitochondrial DNA and morphological data. The new species is morphologically most similar and genetically most closely related to Zhao, 1999 and (Boulenger, 1899), but possesses considerable genetic divergence ( -distance 5.1%-16.7%) and can be differentiated from all other congeners by a combination of the following morphological characters: (1) body size large (total length 514-586 mm) and strongly built; (2) dorsal scale rows 17 throughout, feebly keeled anteriorly and moderately keeled posteriorly; (3) ventral scales 147-152, subcaudal scales 54-62; (4) preocular absent, loreal elongated and touching orbit; (5) supralabials 8-9, fifth and sixth entering obit; (6) anterior temporals short, length 1.74-2.04 times longer than width; (7) maxillary teeth subequal, 28-30; (8) dorsal surface of head with distinct irregular yellow stripes and markings edged with ochre; (9) body with clear black and yellow longitudinal streaks, partly fused to several lighter patches or thicker stripes anteriorly; and (10) venter pale yellow, with asymmetric blackish speckles along outer margin. We present an updated diagnostic key to all members of the genus , and recommendations on the ecological study for the group are provided.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:9007-49-2 (DNA)


  3 / 706 MEDLINE  
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PMID:28617656
Autor:Verma SK; Lindsay DS; Mowery JD; Rosenthal BM; Dubey JP
Endereço:U.S. Department of Agriculture, Agricultural Research Service, Beltsville Agricultural Research Center, Animal Parasitic Diseases Laboratory, Building 1001, Beltsville, Maryland 20705-2350.
Título:Sarcocystis pantherophisi n. sp., from Eastern Rat Snakes (Pantherophis alleghaniensis) as Definitive Hosts and Interferon Gamma Gene Knockout Mice as Experimental Intermediate Hosts.
Fonte:J Parasitol; 103(5):547-554, 2017 Oct.
ISSN:1937-2345
País de publicação:United States
Idioma:eng
Resumo:Here, we report a new species, Sarcocystis pantherophisi n. sp., with the Eastern rat snake (Pantherophis alleghaniensis) as natural definitive host and the interferon gamma gene knockout (KO) mouse as the experimental intermediate host. Sporocysts (n = 15) from intestinal contents of the snake were 10.8 × 8.9 µm. Sporocysts were orally infective to KO mice but not to laboratory-raised albino outbred house mice (Mus musculus). The interferon gamma KO mice developed schizont-associated neurological signs, and schizonts were cultivated in vitro from the brain. Mature sarcocysts were found in skeletal muscles of KO mice examined 41 days postinoculation (PI). Sarcocysts were slender, up to 70 µm wide and up to 3.5 mm long. By light microscopy, sarcocysts appeared thin-walled (<1 µm) without projections. By transmission electron microscopy, the sarcocyst wall was a variant of "type 1" (type 1i, new designation). The parasitophorous vacuolar membrane (pvm) had approximately 100-nm-wide × 100-nm-long bleb-like evaginations interspersed with 100-nm-wide × 650-nm-long elongated protrusions at irregular distances, and invaginations into the ground substance layer (gs) for a very short distance (6 nm). The gs was smooth, up to 500 nm thick, without tubules, and contained a few vesicles. Longitudinally cut bradyzoites at 54 days PI were banana-shaped, 7.8 × 2.2 µm (n = 5). Molecular characterization using 18S rRNA, 28S rRNA, ITS-1, and cox1 genes indicated a close relationship with other Sarcocystis parasites that have snake-rodent life cycles. The parasite in the present study was molecularly and biologically similar to a previously reported isolate (designated earlier as Sarcocystis sp. ex Pantherophis alleghaniensis) from P. alleghaniensis, and it was structurally different from other Sarcocystis species so far described.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:0 (DNA, Protozoan); 0 (RNA, Ribosomal, 18S); 82115-62-6 (Interferon-gamma)


  4 / 706 MEDLINE  
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PMID:28610097
Autor:Angarita-Sierra T
Endereço:YOLUKA ONG, Fundación de Investigación en Biodiversidad y Conservación, Carrera 24 No. 51-81 Piso 3 Grupo de investigación Cladística Profunda y Biogeografía Histórica, Laboratorio de Anfibios, Instituto de Ciencias Naturales, Universidad Nacional de Colombia. teddy.angarita@yoluka.org.co.
Título:A new species of Ninia (Serpentes: Dipsadidae) from Chocó-Magdalena biogeographical province, western Colombia.
Fonte:Zootaxa; 4244(4):478-492, 2017 Mar 22.
ISSN:1175-5334
País de publicação:New Zealand
Idioma:eng
Resumo:We describe a new species of the genus Ninia from the Chocó-Magdalena biogeographic province, which was previously reported as a distinct population of N. maculata or as N. atrata from the western slopes of the Cordillera Occidental of Colombia. The new species is similar to N. atrata, N. celata, N. espinali, N. franciscoi, and N. maculata. It shares the following characteristics with the species mentioned above: 19 dorsal scale rows without reductions; dorsal ground color black or dark brown; white or cream occipital nuchal collar. However, it is easily distinguished from all other congeners because it has a non-regular color pattern in the ventral surfaces of the head and body, subcaudal surface homogeneously black or dark brown, two nasal scales, and one lateral projection ornamented with a large basal hook-shaped spine that is larger than any other spine on the hemipenial body. The presence of a lateral projection on the hemipenial body makes the new species the only member of the genus from South America that shares this feature with its Central American congeners. This feature suggests a closer relationship with this linage. Finally, our results indicate that proper and careful revision of the Ninia atrata species complex will help to understand and clarify the taxonomic composition of the genus.
Tipo de publicação: JOURNAL ARTICLE


  5 / 706 MEDLINE  
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PMID:28610047
Autor:Wang YY; Guo Q; Liu ZY; Lyu ZT; Wang J; Luo L; Sun YJ; Zhang YW
Endereço:State Key Laboratory of Biocontrol / The Museum of Biology, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, P.R. China. wangyy@mail.sysu.edu.cn.
Título:Revisions of two poorly known species of Opisthotropis Günther, 1872 (Squamata: Colubridae: Natricinae) with description of a new species from China.
Fonte:Zootaxa; 4247(4):391-412, 2017 Mar 28.
ISSN:1175-5334
País de publicação:New Zealand
Idioma:eng
Resumo:The previous descriptions of Opisthotropis maxwelli Boulenger, 1914 and O. andersonii (Boulenger, 1888) were considered imperfect due to the limited number of specimens. This may in turn cause a problem for accurate species identification. In our study, the species boundaries of these two species were investigated using an integrative approach incorporating morphological characters and molecular phylogenetic analyses of the mitochondrial Cyt b gene of 26 specimens of nine known Opisthotropis species collected from south-eastern China. Our results surprisingly revealed a new cryptic species, Opisthotropis shenzhenensis sp. nov., from Shenzhen and Dongguan, Guangdong Province, southern China. Further, we re-described O. maxwelli based on several specimens from Fujian and Guangdong, and O. andersonii based on a series of specimens from Hong Kong, Shenzhen and Guangzhou, China. We provide an updated identification key to all described Opisthotropis species from China.
Tipo de publicação: JOURNAL ARTICLE


  6 / 706 MEDLINE  
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PMID:28609871
Autor:Mohapatra PP; Dutta SK; Kar NB; Das A; Murthy BHCK; Deepak V
Endereço:Department of Zoology, Government Science College, Chatrapur, Odisha, India- 761020.. pratyush.kingcobra@gmail.com.
Título:Ahaetulla nasuta anomala (Annandale, 1906) (Squamata: Colubridae), resurrected as a valid species with marked sexual dichromatism.
Fonte:Zootaxa; 4263(2):318-332, 2017 05 09.
ISSN:1175-5334
País de publicação:New Zealand
Idioma:eng
Resumo:In this paper we resolve the taxonomic confusion related to Ahaetulla nasuta anomala (Annandale, 1906). On the basis of molecular and morphological data, we remove it from the synonymy of Ahaetulla nasuta (Lacépède, 1789) and reinstate it as a valid species-Ahaetulla anomala. This species is sexually dichromatic, males are green and females are brown in colour. Though the brown morph morphologically resembles Ahaetulla pulverulenta (Duméril, Bibron & Duméril, 1854) there are significant morphological and genetic differences between these two species. Additional information on taxonomy, natural history and distribution of the species is provided.
Tipo de publicação: JOURNAL ARTICLE


  7 / 706 MEDLINE  
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PMID:28603251
Autor:Quah ESH; Grismer LL; Wood PLJ; Thura MK; Zin T; Kyaw H; Lwin N; Grismer MS; Murdoch ML
Endereço:School of Biological Sciences, Universiti Sains Malaysia, 11800 Minden, Penang, Malaysia.. evanquah@yahoo.com.
Título:A new species of Mud Snake (Serpentes, Homalopsidae, Gyiophis Murphy & Voris, 2014) from Myanmar with a first molecular phylogenetic assessment of the genus.
Fonte:Zootaxa; 4238(4):571-582, 2017 Mar 06.
ISSN:1175-5334
País de publicação:New Zealand
Idioma:eng
Resumo:A newly discovered species of homalopsid snake from the genus Gyiophis Murphy & Voris is described from the lowlands of Mawlamyine District in Mon state, southeastern Myanmar. Gyiophis salweenensis sp. nov. is presumed to be closely related to G. maculosa Blanford and G. vorisi Murphy based on the similarities in pholidosis and patterning but can be separated from G. maculosa by the shape of its first three dorsal scale rows that are square, ventral scale pattern that lacks a central spot, and a faint stripe on dorsal scale rows 1-4. It can be further distinguished from G. vorisi by its lower number of ventral scales (129 vs. 142-152), lower number of subcaudals (30/29 vs. 41-58), narrow rostral scale, and having more rows of spots on the dorsum (four vs. three). A preliminary molecular analysis using 1050 base pairs of cytochrome b (cytb) recovered G. salweenensis sp. nov. as the sister species to the Chinese Mud Snake (Myrrophis chinensis). G. maculosa and G. vorisi were unavailable for the analysis. The discovery of G. salweenensis sp. nov. highlights the need for more surveys into the herpetological diversity of eastern Myanmar which remains very much underestimated.
Tipo de publicação: JOURNAL ARTICLE


  8 / 706 MEDLINE  
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PMID:28544760
Autor:Powers KG; Blackburn DG
Endereço:Dept. of Biology, and Electron Microscopy Center, Trinity College, Hartford, Connecticut.
Título:A Novel Pattern of Yolk Processing in Developing Snake Eggs (Colubridae: Lampropeltini) and its Functional and Evolutionary Implications.
Fonte:J Exp Zool B Mol Dev Evol; 328(5):462-475, 2017 Jul.
ISSN:1552-5015
País de publicação:United States
Idioma:eng
Resumo:Early amniotic vertebrates evolved large-yolked eggs that permitted production of well-developed, terrestrial hatchlings. This reproductive pattern required new mechanisms for cellularizing the yolk and mobilizing it for embryonic use. In birds, cells that line the yolk sac cavity phagocytose and digest the yolk material, a pattern that is commonly assumed to be universal among oviparous amniotes. However, recent evidence challenges the assumption that all squamate reptiles conform to the avian developmental pattern. In this paper, scanning electron microscopy and histology were used to study mechanisms of yolk processing in two colubrid snakes, the kingsnake Lampropeltis getula and the milksnake L. triangulum. Endodermal cells from the yolk sac splanchnopleure proliferate massively as they invade the yolk sac cavity, forming elaborate chains of interlinked cells. These cells grow in size as they phagocytose yolk material. Subsequently, vitelline capillaries invade the masses of yolk-laden cells and become coated with the endodermal cells, forming an elaborate meshwork of cell-coated strands. The close association of cells, yolk, and blood vessels allows yolk material to be cellularized, digested, and transported for embryonic use. The overall pattern is like that of the corn snake Pantherophis guttatus, but contrasts markedly with that of birds. Given recent evidence that this developmental pattern may also occur in certain lizards, we postulate that it is ancestral for squamates. Studies of lizards, crocodilians, and turtles are needed to clarify the evolutionary history of this pattern and its implications for the evolution of the amniotic (terrestrial) vertebrate egg.
Tipo de publicação: JOURNAL ARTICLE


  9 / 706 MEDLINE  
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PMID:28425037
Autor:de Santana Miglionico MT; Viana LA
Endereço:Programa de Pós-Graduação em Biodiversidade e Saúde, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil 4365, Rio de Janeiro, RJ, 21040-360, Brazil.
Título:A new species of Caryospora Léger, 1904 (Apicomplexa: Eimeriidae) from the Guanabara spotted night snake Siphlophis pulcher (Raddi) (Reptilia: Dipsadidae) in the Atlantic Forest, Brazil.
Fonte:Syst Parasitol; 94(5):621-625, 2017 Jun.
ISSN:1573-5192
País de publicação:Netherlands
Idioma:eng
Resumo:A new coccidian species of the genus Caryospora Léger, 1904 (Apicomplexa, Eimeriidae) is described based on material from the Guanabara spotted night snake Siphlophis pulcher (Raddi) (Reptilia: Dipsadidae) in a coastal area of the Atlantic Forest in Ilha Grande Island, state of Rio de Janeiro, southeastern Brazil. Caryospora ceadsensis n. sp. possesses spheroidal to slightly subspheroidal oöcysts measuring 17-24 × 17-24 (22.1 × 22.0) µm, with a c.1.3 µm thick bi-layered wall (inner layer smooth, outer layer slightly striated), length/width (L/W) ratio of 1.0-1.1 (1.0) and a highly refractive polar granule. Sporocysts are ellipsoidal, 11-17 × 10-13 (14.7 × 11.2) µm, with a L/W ratio of 1.0-1.5 (1.3), with a nipple-like Stieda body (1.1 µm high and 2.9 µm wide) and a large, bubble-shaped sub-Stieda body 1.7 µm high and 3.8 µm wide (1.0-2.0 × 3.0-4.5 µm). Sporocyst residuum composed of granules of differing sizes. Sporozoites with striations. This is the sixth record of a species of Caryospora in snakes of the family Dipsadidae in Brazil.
Tipo de publicação: JOURNAL ARTICLE


  10 / 706 MEDLINE  
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PMID:28380330
Autor:Neuman-Lee LA; Brodie ED; Hansen T; Brodie ED; French SS
Endereço:Department of Biology, Utah State University, Logan, UT 84322, USA. Electronic address: lorin215@gmail.com.
Título:To stress or not to stress: Physiological responses to tetrodotoxin in resistant gartersnakes vary by sex.
Fonte:Comp Biochem Physiol A Mol Integr Physiol; 209:34-40, 2017 Jul.
ISSN:1531-4332
País de publicação:United States
Idioma:eng
Resumo:The activation of the hypothalamic pituitary adrenal (HPA) axis is one of the most important physiological processes in coping with any deviation in an organism's homeostasis. This activation and the secretion of glucocorticoids, such as corticosterone, allow organisms to cope with perturbations and return to optimal physiological functioning as quickly as possible. In this study, we examined the HPA axis activation in common gartersnakes (Thamnophis sirtalis) as a response to a natural toxin, tetrodotoxin (TTX). This neurotoxin is found in high levels in the Rough-skinned Newt (Taricha granulosa), which is a prey item for these snakes. To consume this toxic prey, these snakes have evolved variable resistance. We hypothesized that the more resistant individuals would show a lower HPA axis response than less resistant individuals, as measured by corticosterone (CORT) and bactericidal ability, which is a functional downstream measurement of CORT's activity. We determined "resistance level" for tetrodotoxin from each individual snake by determining the dose which reduced race speed by 50%. Individuals were injected them with an increasing amount of tetrodotoxin (10, 25, and 50 MAMUs) to determine this value. Thirty minutes after every injection, we gathered blood samples from each snake. Our results show that, while there were no significant differences among individual CORT levels in a dose-dependent manner, female snakes did have a larger stress response when compared to both males and juveniles. Different life-histories could explain why females were able to mount a higher HPA axis response. However, TTX had no downstream effects on bactericidal ability, although juveniles had consistently lower values than adults. Our research shows a possible dichotomy between how each sex manages tetrodotoxin and gives way for a more comprehensive analysis of tetrodotoxin in an ecological context.
Tipo de publicação: JOURNAL ARTICLE
Nome de substância:4368-28-9 (Tetrodotoxin); W980KJ009P (Corticosterone)



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