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.
Keywords: Reptilia, External morphology, Biogeography of the Colombian Pacific lowlands, Hemipenis, Ninia atrata, Ninia maculata, taxonomy
Ninia teresitae sp. nov.
FIGURE 2. General view of the holotype (ICN 12527) of Ninia teresitae sp. nov., in life (A), dorsal (B) and ventral (C) views after its preservation.
Etymology. The specific epithet teresitae represent the Latin translation of the nickname from the Spanish “Teresita” and is given in honor to the grandmother of the first author, Maria Teresa Guerrero (1915−2013). “Teresita” was one of the most influential persons in her grandson’s life, who never failed to support him and encouraged his endless passion for snakes.
Teddy Angarita-Sierra and John D. Lynch. 2017. A New Species of Ninia (Serpentes: Dipsadidae) from Chocó-Magdalena Biogeographical Province, western Colombia. Zootaxa. 4244(4); 478–492. DOI: 10.11646/zootaxa.4244.4.2
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شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
An increase in ecological opportunities, either through changes in the environment or acquisition of new traits, is frequently associated with an increase in species and morphological diversification. However, it is possible that certain ecological settings might prevent lineages from diversifying. Arboreality evolved multiple times in vipers, making them ideal organisms for exploring how potentially new ecological opportunities affect their morphology and speciation regimes. Arboreal snakes are frequently suggested to have a very specialized morphology, and being too large, too small, too heavy, or having short tails might be challenging for them. Using trait-evolution models, we show that arboreal vipers are evolving towards intermediate body sizes, with longer tails and more slender bodies than terrestrial vipers. Arboreality strongly constrains body size and circumference evolution in vipers, while terrestrial lineages are evolving towards a broader range of morphological variants. Trait-dependent diversification models, however, suggest similar speciation rates between microhabitats. Thus, we show that arboreality might constrain morphological evolution but not necessarily affect the rates at which lineages generate new species.
The arboreal Stejneger's Pitviper (Trimeresurus stejnegeri).
Photo: M. Martins
Laura Rodrigues Vieira de Alencar, Marcio Martins, Gustavo Burin and Tiago Bosisio Quental. 2017. Arboreality Constrains Morphological Evolution but Not Species Diversification in Vipers. Proceedings of the Royal Society B: Biological Sciences. 284(1869)DOI: 10.1098/rspb.2017.1775
كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
We describe a new species of coralsnake from northern Dinagat Island, southeastern Philippines. The discovery of this new species comes as a surprise because it is phenotypically distinct from all other Philippine coralsnakes and has a close phylogenetic affinity to the blue coralsnakes of the Sunda Shelf. The new species is distinguished from all Philippine and other Southeast Asian taxa by its large body size and ventral scale counts; its black head and neck; an alternating, broadly banded color pattern of black and off-white; and a bright orange tail. We use DNA sequence data to investigate the phylogenetic placement of the new species and that of several other populations of Philippine coralsnakes with respect to other Southeast Asian and Australasian elapids. Our results corroborate the uniqueness of the new species with respect to all other Philippine and Sundaic taxa, including the species most closely related to it: Calliophis bivirgatus, C. bilineatus, C. philippinus, and C. suluensis. We summarize phylogenetic, biogeographic, and phenotypic character data that substantiate the elevation of Philippine species of Calliophis(formerly considered subspecies of C. intestinalis: C. bilineatus, C. philippinus, and C. suluensis) and Hemibungarus(formerly subspecies of H. calligaster: H. calligaster, H. gemianulis, and H. mcclungi) to the level of full species. The allopatric distributions of these taxa emphasize the systematic and biogeographical significance of the newly discovered taxon: a poorly understood and independent colonization of the Philippine Archipelago by elapid snakes.
Keywords:Calliophis salitan, Caraga Region, Mindanao PAIC, new species, false coralsnakes
Calliophis salitan adult male holotype (PNM 9844, formerly KU 310164; 997 mm total length [TL]), illustrated by E.F. Jones.
Calliophis salitan sp. nov.
Etymology.— The specific epithet is a noun in apposition and is derived from the Tagalog (Filipino) term salitan, meaning‘‘alternating,’’in reference to the distinctive, alternating black and off-white banded color pattern characteristic of the new species. Suggested English common name: Dinagat Island Banded Coralsnakes.
Habitat, distribution, and natural history.— The only known locality for Calliophis salitan is the low foothill of Mt. Cambinlia, Barangay Santiago, Municipality Loreto, Dinagat Island (Fig. 8), Philippines, where it was collected from an elevation of 195 m. This locality, dominated by selectively logged, regenerating second-growth forest, is situated at the northern end of the island, and has a tropical climate, with a mean annual precipitation of 3580 mm (recorded at Loreto town proper,,1 km from the type locality; higher precipitation values are possible at higher elevations on Mount Cambinlia). Precipitation is highest during December (~539 mm) and lowest in August (averaging 143 mm),and the mean annual temperature is 278C. The type specimen was collected between 1900 and 2200 h, and was actively crawling along a stream bed with reduced water flow between intermittent pools. The specimen was obtained at the end of July, toward the end of the dry season.
Rafe M. Brown, Utpal Smart, Alan E. Leviton, and Eric N. Smith. 2018. A New Species of Long-glanded Coralsnake of the Genus Calliophis (Squamata: Elapidae) from Dinagat Island, with Notes on the Biogeography and Species Diversity of Philippine Calliophis and Hemibungarus. Herpetologica. In-Press. DOI: 10.1655/Herpetologica-D-17-00008
كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
Figure 2. Photographs of some Ecuadorian species of Atractus in life: A. carrioni MZUTI 4194 (a), MZUTI 4195 (b), A. duboisi MZUTI 3640 (c), A. dunni MZUTI 4318 (d), A. dunni MZUTI 2189 (e), A. elaps AMARU SN (f), A. gigas MZUTI 3286 (g), A. iridescens MZUTI 3680 (h), A. iridescens QCAZ 8072 (i)
We present a molecular phylogeny of snake genus Atractus, with an improved taxon sampling that includes 30 of the 140 species currently recognized. The phylogenetic tree supports the existence of at least three new species in the Pacific lowlands and adjacent Andean slopes of the Ecuadorian Andes, which we describe here. A unique combination of molecular, meristic and color pattern characters support the validity of the new species. With the newly acquired data, we propose and define the A. iridescens species group, as well as redefine the A. roulei species group. The species A. iridescens is reported for the first time in Ecuador, whereas A. bocourti and A. medusa are removed from the herpetofauna of this country. We provide the first photographic vouchers of live specimens for A. multicinctus, A. paucidens and A. touzeti, along with photographs of 19 other Ecuadorian Atractus species. The current status of A. occidentalis and A. paucidens is maintained based on the discovery of new material referable to these species. With these changes, the species number reported in Ecuador increases to 27, a number that is likely to increase as material not examined in this work becomes available and included in systematic studies.
Keywords: Pacific lowlands, biodiversity, Ecuador, groundsnakes, Atractus, phylogeny, new species
Figure 2. Photographs of some Ecuadorian species of Atractus in life: A. carrioni MZUTI 4194 (a), MZUTI 4195 (b), A. duboisi MZUTI 3640 (c), A. dunni MZUTI 4318 (d), A. dunni MZUTI 2189 (e), A. elaps AMARU SN (f), A. gigas MZUTI 3286 (g), A. iridescens MZUTI 3680 (h), A. iridescens QCAZ 8072 (i), A. iridescens MZUTI 4697 (j), A. iridescens MZUTI 3548 (k), A. major MZUTI 4973 (l), A. microrhynchus MZUTI 5109 (m), A.modestus (n), A. multicinctus MZUTI 5106 (o), A. occidentalis MZUTI 1385 (p), A. occidentalis MZUTI 3323 (q), A. paucidens MZUTI 5102 (r), A. resplendens MZUTI 3996 (s), A. roulei MZUTI 4503 (t), A. savagei MZUTI 4916 (u), A. snethlageae (v), A. touzeti ANF 2390 (w), and A. typhon MZUTI 5110.
Figure 2. Photographs of some Ecuadorian species of Atractus in life: A. carrioni MZUTI 4194 (a), MZUTI 4195 (b), A. duboisi MZUTI 3640 (c), A. dunni MZUTI 4318 (d), A. dunni MZUTI 2189 (e), A. elaps AMARU SN (f), A. gigas MZUTI 3286 (g), A. iridescens MZUTI 3680 (h), A. iridescens QCAZ 8072 (i)
New taxa and systematic arrangements derived from the analyses
We seek here to only name or redelimit Atractus species groups that are supported in our molecular phylogeny and share features of their coloration pattern and lepidosis. The first such groups is the clade comprising A. cerberus sp. n., A. dunni, A. esepe sp. n., A. iridescens, A. microrhynchus and A. occidentalis. The other is the one comprising A. carrioni, A. lehmanni, A. pyroni sp. n. and A. roulei.
Atractus iridescens species group
Content.A. cerberus sp. n., A. dunni, A. esepe sp. n., A. iridescens, A. microrhynchus and A. occidentalis
Atractus roulei species group
Content.Atractuscarrioni, A. lehmanni, A. pyroni sp. n. and A. roulei.
Figure 2. Photographs of some Ecuadorian species of Atractus in life: A. iridescens MZUTI 4697 (j), A. iridescens MZUTI 3548 (k), A. major MZUTI 4973 (l), A. microrhynchus MZUTI 5109 (m), A.modestus (n), A. multicinctus MZUTI 5106 (o), A. occidentalis MZUTI 1385 (p), A. occidentalis MZUTI 3323 (q), A. paucidens MZUTI 5102 (r), A. resplendens MZUTI 3996 (s), A. roulei MZUTI 4503 (t), A. savagei MZUTI 4916 (u), A. snethlageae (v), A. touzeti ANF 2390 (w), and A. typhon MZUTI 5110.
Figure 5. Adult male holotype MZUTI 4330 (a) and adult male paratopotype (b) of Atractus cerberus MZUTI 5108.
Atractus cerberus sp. n.
Proposed standard English name: Cerberus Groundsnake
Proposed standard Spanish name: Tierrera cancerbera
Natural history: The two known specimens of Atractuscerberus were found in an isolated patch of deciduous lowland forest surrounded by dry lowland shrubland. MZUTI 4330 was found active on leaf litter at 19h29, in 80% closed canopy secondary forest far from streams. The night was warm and there was drizzle the night before. MZUTI 5108 was found crossing a forest trail close to an open area at 10h00 during a sunny morning after a rainy night.
Distribution: Known only from the type locality, Pacoche, in the Ecuadorian province of Manabí at 280–324 m (Fig. 3). This locality is 3 km airline distance from the shoreline.
Etymology: The specific epithet “cerberus” is derived from the name of the Greek monster Kérberos. In Greek mythology, Kérberos is a monstrous multi-headed dog that guards the gates of the underworld, preventing the dead from leaving. Here, we use this word in allusion to the type locality, at the gates of the newly formed “Refinería del Pacífico”, a massive industrial oil-processing plant that can easily be likened to the underworld.
Atractus esepe sp. n.
Proposed standard English name: Indistinct Groundsnake
Proposed standard Spanish name: Tierrera indistinta
Natural history: The two known specimens of Atractusesepe were found actively foraging among soil and roots in secondary evergreen lowland forest at least 400 m from the nearest natural body of water. They were found by night at 20h00 after a warm, sunny day.
Distribution: Known only from the type locality, Caimito, in the Ecuadorian province of Esmeraldas at 102 m (Fig. 3). This locality is 1.3 km airline distance from the shoreline.
Etymology: The specific epithet esepe is derived from the Spanish pronunciation of “sp.”, which is the abbreviation for the Latin word species. Here, we use this word in allusion to how the majority of Ecuadorian researchers refer to Atractus specimens found in the field.
Figure 7. Adult female holotype of Atractus pyroni. MZUTI 5107. Scale = 1 cm.
Atractus pyroni sp. n.
Proposed standard English name: Pyron’s Groundsnake
Proposed standard Spanish name: Tierrera de Pyron
Natural history: The only known specimen of Atractuspyroni was found dead on a dirt road surrounded by silvopastures and remnants of native montane cloudforest.
Distribution: Known only from the type locality, between Balzapamba and Bilován, in the Ecuadorian province of Bolívar at 2026 m (Fig. 7).
Etymology: Named after R. Alexander Pyron, one of the most prolific contemporary herpetologists, in recognition of his invaluable contribution to systematics and evolution of the world’s reptiles.
Alejandro Arteaga, Konrad Mebert, Jorge H. Valencia, Diego F. Cisneros-Heredia, Nicolás Peñafiel, Carolina Reyes-Puig, José L. Vieira-Fernandes and Juan M. Guayasamin. 2017. Molecular Phylogeny of Atractus (Serpentes, Dipsadidae), with Emphasis on Ecuadorian Species and the Description of Three New Taxa. ZooKeys. 661: 91-123. DOI: 10.3897/zookeys.661.11224
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شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
The island of New Guinea has been identified as biologically megadiverse but many taxa are still poorly known. This is especially the case for many of the island’s snakes, which by their very nature can be difficult to collect and study. Here we examine the phylogenetic and phylogeographic structure of a poorly studied snake genus, Stegonotus, focusing on the species of New Guinea; until now, Stegonotus has never been examined using modern phylogenetic methods. Using molecular data from 49 individuals representing eight of the ten described species, and including all New Guinea taxa, we estimate a multilocus phylogeny and examine population structure to help identify undescribed taxa. We use morphological data from the corresponding museum vouchered specimens (where available) and also examine additional specimens for taxa not included in the molecular data set to determine morphological differences among putative taxa. We find molecular evidence for four new species of Stegonotus, both morphologically obvious and cryptic, and describe them herein. The recognition of these four species indicates that Stegonotus diversity has been previously underestimated and also suggests that there are likely additional undescribed taxa within the genus. These four taxa increase the number of described species by 40% and further confirm New Guinea as the centre of diversity for the genus.
KEYWORDS:Australasia, colubrine, Indonesia, integrative taxonomy, phylogenetics
Figure 1. Photographs of six New Guinea Stegonotus species in life including voucher numbers: (a) Stegonotus cucullatus LSUMZ 94371, (b) Stegonotus diehli LSUMZ 92345, (c) Stegonotus modestus LSUMZ 92327, (d) Stegonotus heterurus BPBM 22556, (e) Stegonotus parvus LSUMZ 92335, (f) Stegonotus guentheri LSUMZ 94386.
Photos from Christopher C. Austin (a, b, c, e, f) and F. Kraus (d).
Photographs of holotype Stegonotus iridis sp. nov. MZB.Ophi.3306; dorsal of body, ventral of body.
Photos from Stephen J. Richards.
Stegonotus iridis sp. nov.
Etymology: The species epithet is a noun in apposition and taken from the Latin word for rainbow. It refers to the high level of iridescence shown both dorsally and ventrally by this species.
Natural history and distribution: Currently known only from the Raja Ampat islands of Batanta, Salawati and Waigeo in eastern Indonesia where all of the animals encountered were active on the forest floor in moderately to heavily disturbed lowland (< 100 m asl) rainforest at night. The pale colour of this species made them extremely conspicuous against the dark forest floor.
Stegonotus derooijae sp. nov. MZB.Ophi.3288
Photos from Stephen J. Richards.
Stegonotus derooijae sp. nov.
Etymology: The species epithet is a noun in the genitive case and is a patronym in honour of Dr Nelly De Rooij, who described many taxa from New Guinea and Indonesia, including Stegonotus florensis.
Natural history and distribution: Currently known only from the Raja Ampat islands of Batanta, Salawati and Waigeo in eastern Indonesia. This small, slender species was active on the forest floor in moderately to heavily disturbed lowland (< 100 m above sea level) rainforest at night. At each site it occurred in sympatry with S. iridis sp. nov., described above.
Stegonotus melanolabiatus sp. nov.
Etymology: The species epithet comes from the Greek melano meaning black or dark and the Latin word labia for lips. The name refers to the dark coloration of the labial scales of this species.
Natural history and distribution: No information is known about the natural history of S.melanolabiatus. Stegonotus melanolabiatus sp. nov. is found south of the central mountain ranges (Figure 3) in Southern Highlands and Chimbu Provinces of Papua New Guinea. It may also occur in other provinces and regions south of the central cordillera across New Guinea.
Stegonotus admiraltiensis sp. nov.
Etymology: The species epithet refers to the Admiralty Islands where this species is found, an archipelago of 18 islands to the north of New Guinea, comprising Manus Province, Papua New Guinea.
Natural history and distribution: As with all New Guinea Stegonotus, S. admiraltiensis sp. nov. is nocturnal. All four specimens were collected at night as they were moving on the forest floor on the leaf litter. Typical for Stegonotus, once picked up S. admiraltiensis sp. nov. rapidly attempted to bite the collector’s hand and writhed violently in a side-to-side motion. Nothing more is known about the natural history or ecology of S. admiraltiensis sp. nov. Stegonotus admiraltiensis sp. nov. is found on the islands of Rambutyo and Los Negros in Manus Province of Papua New Guinea. Based on descriptions of similar specimens from Manus (McDowell 1972) and recent collections there by SJR that will be registered in the near future (Richards and Aplin 2015), we conclude that S. admiraltiensis sp. nov. is also found on Manus Island proper and that all specimens of Stegonotus from the Admiralty Islands are S. admiraltiensis sp. nov.
Sara Ruane, Stephen J. Richards, John D. McVay, Burhan Tjaturadi, Keliopas Krey and Christopher C. Austin. 2017. Cryptic and Non-Cryptic Diversity in New Guinea Ground Snakes of the Genus Stegonotus Duméril, Bibron and Duméril, 1854: A Description of Four New Species (Squamata: Colubridae). Journal of Natural History. DOI: 10.1080/00222933.2017.1391959
كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
We generated a novel database of Neotropical snakes (one of the world's richest herpetofauna) combining the most comprehensive, manually compiled distribution dataset with publicly available data. We assess, for the first time, the diversity patterns for all Neotropical snakes as well as sampling density and sampling biases.
Main types of variables contained
We compiled three databases of species occurrences: a dataset downloaded from the Global Biodiversity Information Facility (GBIF), a verified dataset built through taxonomic work and specialized literature, and a combined dataset comprising a cleaned version of the GBIF dataset merged with the verified dataset.
Spatial location and grain
Neotropics, Behrmann projection equivalent to 1° × 1°.
Time period
Specimens housed in museums during the last 150 years.
Major taxa studied
Squamata: Serpentes.
Software format
Geographical information system (GIS).
Results
The combined dataset provides the most comprehensive distribution database for Neotropical snakes to date. It contains 147,515 records for 886 species across 12 families, representing 74% of all species of snakes, spanning 27 countries in the Americas. Species richness and phylogenetic diversity show overall similar patterns. Amazonia is the least sampled Neotropical region, whereas most well-sampled sites are located near large universities and scientific collections. We provide a list and updated maps of geographical distribution of all snake species surveyed.
Main conclusions
The biodiversity metrics of Neotropical snakes reflect patterns previously documented for other vertebrates, suggesting that similar factors may determine the diversity of both ectothermic and endothermic animals. We suggest conservation strategies for high-diversity areas and sampling efforts be directed towards Amazonia and poorly known species.
Figure 1. Neotropical region and ecoregion limits adopted here (sensu Olson et al., 2001), together with representative snakes species recorded for Central America Montane Forests: 1.1 Boa constrictor, 1.2 Oxybelis aeneus; Amazonia Most Forests: 1.3 Philodryas argentea, 1.4 Rhinobothryum lentiginosum, 1.5 Eunectes murinus, 1.6 Siphlophis compressus, 1.7 Amerotyphlops reticulatus, 1.8 Lachesis muta; Cerrado: 1.9 Imantodes cenchoa, 1.10 Apostolepis flavotorquata, 1.11 Bothrops lutzi, 1.12 Micrurus frontalis, 1.13 Erythrolamprus typhlus, 1.14 Phalotris lativittatus, 1.15 Xenopholis undulatus, 1.16 Oxyrhopus rhombifer, 1.17 Rhachidelus brazili; Chaco: 1.18 Psomophis genimaculatus, 1.19 Philodryas baroni, 1.20 Phimophis vittatus; Guianian Moist Forests: 1.21 Corallus caninus, 1.22 Anilius scytale, 1.23 Amerotyphlops brongersmianus; Caatinga: 1.24 Erythrolamprus viridis, 1.25 Thamnodynastes phoenix, 1.26 Bothrops erythromelas; and in the Atlantic Forest: 1.27 Atractus maculatus, 1.28 Chironius bicarinatus, 1.29 Tropidodryas striaticeps, 1.30 Liotyphlops beui, 1.31 Oxyrhopus guibei, 1.32 Dipsas albifrons, 1.33 Bothrops jararaca, 1.34 Corallus hortulanus, 1.35 Erythrolamprus atraventer.
The abbreviations indicate common life habits of the Neotropical snakes: aquatic (Aq), arboreal (Ar), fossorial (F), terrestrial (T).
Photograph credits: Cristiano C. Nogueira (10, 12), Crizanto C. Brito (27), Henrique B. Braz (14), Ivan Sazima (24, 35), Luiz C. Turci (7), Marcio Martins (4), Marco Sena (6), Martin Jansen (9, 13, 18, 23, 31), Otavio A. V. Marques (2, 3, 5, 15, 16, 17, 19, 20, 21, 22, 28, 30, 32), Ricardo J. Sawaya (33), Thaís B. Guedes (1, 8, 11, 25, 26, 29, 34)
Our study demonstrates that Neotropical snake diversity is unevenly distributed, with some ecoregions, such as the Cerrado, containing a disproportionately high diversity. We also showed that merging public and manually compiled data sources is likely to provide the largest taxonomic and geographical coverage for any system under study. However, a proper taxonomic verification, examination and assessment of biases of the public dataset proved crucial. As a result, we can now provide a solid and reliable foundation for any kind of meta-analysis, including the assessment of climate change effects, conservation strategies or design of future research agendas. Conservation priorities should focus on areas of high diversity values as well as high threat by landscape changes. Finally, we found highest diversity values in forested areas, reinforcing the need for general habitat protection compared with actions that are targeting specific species.
In order to increase our knowledge about Neotropical snakes, a geographically and taxonomically focused sampling is required, targeting Amazonia and those species whose distributions are so far largely unknown.
كيف تحصل على مدونة جاهزة بآلاف المواضيع والمشاركات من هنا
شاهد قناة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على اليوتيوب لمزيد من الشرح من هنا
رابط مدونة منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات في أي وقت حــــتى لو تم حذفها من هنا شاهد صفحة منتدى مدونات بلوجر جاهزة بألاف المواضيع والمشاركات على الفيس بوك لمزيد من الشرح من هنا
تعرف على ترتيب مواضيع منتدى مدونات بلوجر جاهزة بآلاف المواضيع والمشاركات (حتى لا تختلط عليك الامور) من هنا
ملاحظة هامة: كل عمليات تنزيل، رفع، وتعديل المواضيع الجاهزة تتم بطريقة آلية، ونعتذر عن اي موضوع مخالف او مخل بالحياء مرفوع بالمدونات الجاهزة بآلاف المواضيع والمشاركات، ولكم ان تقوموا بحذف هذه المواضيع والمشاركات والطريقة بسيطة وسهلة. ــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــــسلامـ.
