Annotated Checklist and Provisional Conservation Status of Namibian Reptiles.
168 Seiten. Windhoek. ISBN
An annotated checklist of indigenous and potentially indigenous Namibian terrestrial, aquatic and marine reptiles is presented. The purpose is to serve as an interim description of Namibian reptile diversity, to establish a taxonomic and biogeographical baseline, and as a preliminary review of the conservation status of Namibian reptiles. Two hundred and forty species of indigenous reptiles are presently known to occur in Namibia. These species comprise an array of approximately 265 described (but not always recognized) taxa, several of which are probably unwarranted. Species accounts are presented for all these species. Four accounts are for new species currently being described. Nineteen species have not yet been recorded from Namibia, but are expected to (accounts given) and another 6 species are less likely to occur (no accounts given). Full accounts are given for the 17 species which have been formally recorded in the past, but the lack of recent evidence suggests that the species is now locally extinct, the original report erroneous, or the species’ occurred as vagrants. Four additional species had been included on various published lists in the past, but have never been formally documented, no specimens are known to exist, and it is unlikely that the species would occur today even as vagrants (no accounts given). In total, 276 species-accounts are presented. Each account cites the original reference and type locality for each taxon, and a short description of the Namibian distribution. Emphasis is placed on Namibian and international legal and conservation status. Eighty-five species (33%) were found to be of local conservation concern. Gaps in knowledge (e.g. taxonomy, biogeography, and conservation status), where future research should be directed, are noted.
The Herpetology of the Southern Kalahari Domain.
Supplement to Koedoe 1984: 171-186.
The herpetofauna of the southrn Kalahari has mixed affinities, as this area lies on a rainfall gradient in a critical area where a transition between the arid south-west and the moister northe-east takes place. As the variation in substrate type is relatively limited, the effect of the rainfall gradient appears to influence and determine the range limits of many taxa in which of 55 recorded reptiles, 11 western taxa overlap or form a parapatric zone with 25 eastern taxa, while the remaining taxa are endemic or wide-ranging.
Zur Herpetofauna des Brandbergs, Südwest-Afrika.
Bonn. zool. Beitr. 34 (1-3): 293-309
Der Brandberg liegt isoliert am Rande der Vornamib-Flächen innerhalb der Nord-Süd verlaufenden Bergränder der Großen Randstufe. Floristisch macht er einen Teil der Karroo-Namibischen Florenregion aus. Es herrscht troisches, episodisch-periodisch sommerfeuchtes Halbwüsten bis Trockenklima. Herpetofaunistische Grenzen lassen sich nicht genau definieren. Die Herpetofauna umfasst 41 Formen (5 Froschlurche, 26 Eidechsen, 10 Schlangen); sie wird dargestellt und bestehende Affinitäten zu den umliegenden zoogeografischen Subregionen werden erörtert. Als Neunachweise für den Brandberg konnten Bufo d. dombensis, Tomopterna marmorata, Python anchietae, Boaedon f. fuliginosus, Naja nigricollis nigricincta und Bitis a. arientans belegt werden.
Vorläufige Liste der Schlangen des Tai-Nationalparks / Elfenbeinküste und angrenzender Gebiete.
SALAMANDRA 36(1): 25-38
Wir stellen die Schlangenfauna des Tai-Nationalparks (TNP) mit Angabe weiterer biologischer Daten vor. Insgesamt sind nun 39 Schlangenarten aus dem TNP bekannt. Im Primär-Regenwald wurden 22 und in offeneren Habitaten beziehungsweise am Waldrand 17 Schlangenarten gefunden. 15 Arten waren arborikol, 19 lebten am Boden und fünf unterirdisch. Wir gehen davon aus, daß die bisherigen Nachweise etwa zwei Drittel der für diesen letzten großen Regenwald Westafrikas zu erwartenden Arten ausmachen.
Rediscovery of the Mount Nimba Reedfrog, Hyperolius nimbae LAURENT, 1958, in western Ivory Coast (Anura: Hyperoliidae).
HERPETOZOA 29(1/2): 3-13
Die vorliegende Arbeit berichtet über die Wiederentdeckung von Hyperolius nimbae LAURENT, 1958, einer Riedfroschart, die nur vom Fuß der östlichen Flanke des Mount Nimba im Westen der Elfenbeinküste bekannt ist. Die Art wurde 1958 beschrieben und 1963 zum letzten Mal beobachtet. Siebenundvierzig Jahre später wurden innerhalb des bekannten Verbreitungsgebietes kleine Populationen dieses Riedfrosches in der Nähe der Dörfer Dagbonpleu, Danipleu, Kouan-Houlé und Zéalé wiederentdeckt. Allerdings konnten nur insgesamt sieben Exemplare registriert werden. Die Lebensräume zeigten unterschiedliche Grade der degradierung von Sumpfwäldern bis zu Reisfeldern in degradiertem Wald oder Sekundärwuchs. Der starke menschliche Einfluß im Gebiet, besonders seine landwirtschaftliche Nutzung, könnte das langfristige Überleben der Art gefährden. Die Autoren empfehlen eine intensive weitere Suche nach bestehenden Populationen und deren Monitoring, um die Gefährdung für das Überleben von H. nimbae abzuschätzen.
Herpetofauna, Parc National des Volcans, North Province, Republic of Rwanda.
Check List 6 (4): 525-531. Jan. 2010. DOI: 10.15560/6.4.525
Herein is presented a list of the reptiles and anurans from the Parc National des Volcans (PNV)(01°43’ S, 29°52’ W), an area in the west and north provinces of the Republic of Rwanda in the Albertine Rift region of Africa. Fieldwork was conducted between two and six days per week from June through August 2007 and 2008. We also conducted literature searches of all historical expeditions within the park for species records. Seventeen species of reptiles and anurans are recorded from the PNV. Nine of the species were anurans, distributed in five families: Arthroleptidae (3), Bufonidae (1), Hyperoliidae (3), Phrynobatrachidae (1), and Pipidae (1). Eight species of reptiles were recorded from five families: Chamaeleonidae (1), Lacertidae (2), Scincidae (2), Colubridae (2), and Viperidae (1). Eight of the seventeen species found in the PNV are endemic to the Albertine Rift.
Did Komodo dragons evolve to eat pygmy elephants?
Nature 326: 832.
All the large mammal species on which Komodo Dragons now prey were introduced to Flores by humans after BC 3000. What did they eat before then? During the Pleistocene, Flores supported two species of now-extinct elephants, the small Stegodon trigonocephalus florensis and the pygmy S. sompoensis (also called S. timoriensis). Hence Auffenberg's suggestion' that the Dragons evolved as a specialized predator on pygmy elephants, formerly the sole large prey available on Flores.
Limitations of Climatic Data for Inferring Species Boundaries: Insights from Speckled Rattlesnakes.
PLoS ONE 10(6): e0131435. doi:10.1371/journal.pone.013143
Phenotypes, DNA, and measures of ecological differences are widely used in species delimitation. Although rarely defined in such studies, ecological divergence is almost always approximated using multivariate climatic data associated with sets of specimens (i.e., the “climatic niche”); the justification for this approach is that species-specific climatic envelopes act as surrogates for physiological tolerances. Using identical statistical procedures, we evaluated the usefulness and validity of the climate-as-proxy assumption by comparing performance of genetic (nDNA SNPs and mitochondrial DNA), phenotypic, and climatic data for objective species delimitation in the speckled rattlesnake (Crotalus mitchellii) complex. Ordination and clustering patterns were largely congruent among intrinsic (heritable) traits (nDNA, mtDNA, phenotype), and discordance is explained by biological processes(e.g., ontogeny, hybridization). In contrast, climatic data did not produce biologically meaningful clusters that were congruent with any intrinsic dataset, but rather corresponded to regional differences in atmospheric circulation and climate, indicating an absence of inherent taxonomic signal in these data. Surrogating climate for physiological tolerances adds artificial weight to evidence of species boundaries, as these data are irrelevant for that purpose. Based on the evidence from congruent clustering of intrinsic datasets, we recommend that three subspecies of C.mitchellii be recognized as species: C.angelensis,C.mitchellii, and C.Pyrrhus.
Evolution of rattlesnakes (Viperidae; Crotalus) in the warm deserts of western North America shaped by Neogene vicariance and Quaternary climate change.
Molecular Ecology (2006) 15, 3353 – 3374. doi: 10.1111/j.1365-294X.2006.03007.x
During Pleistocene, the Laurentide ice sheet rearranged and diversified biotic distributionsin eastern North America, yet had minimal physical impact in western North Americawhere lineage diversification is instead hypothesized to result from climatic changes. If Pleistocene climatic fluctuations impacted desert species, the latter would reflect patterns of restricted gene flow concomitant with indications of demographic bottlenecks. Accordingly, molecular evidence for refugia should be present within these distributions and for subsequent range expansions as conditions improved. We sought answers to these questions by evaluating mitochondrial DNA (mtDNA) sequences from four species of rattle-snakes [Crotalus mitchellii (speckled rattlesnake), Crotalus cerastes (sidewinder), Crotalus tigris (tiger rattlesnake), Crotalus ruber (red diamond rattlesnake)] with distributions restricted to desert regions of southwestern North America. We inferred relationships using parsimony and maximum likelihood, tested intraspecific clades for population expansions, applied an isolation-with-migration model to determine bi-directional migration rates (m) among regions, and inferred divergence times for species and clades by applying a semiparametric penalized likelihood approach to our molecular data. Evidence for significant range expansion was present in two of eight regions in two species (Crotalus mitchellii pyrrhus, C. tigris region north). Two species (C. cerastes, C. mitchellii) showed a distribution concomitant with northward displacement of Baja California from mainland México, followed by vicariant separation into subclades. Effects of Pleistoceneclimate fluctuations were found in the distributions of all four species. Three regional diversification patterns were identified: (i) shallow genetic diversity that resulted from Pleistocene climatic events (C. tigris, C. ruber); (ii) deep Pleistocene divisions indicating allopatric segregation of subclades within refugia (C. mitchellii, C. cerastes); and (iii) line-age diversifications that extended to Pliocene or Late Miocene (C. mitchellii, C. cerastes). Clade-diversifying and clade-constraining effects impacted the four species of rattlesnakes unequally. We found relatively high levels of molecular diversification in the two most broadly distributed species (C. mitchellii, C. cerastes), and lower levels of genetic diversification in the two species (C. tigris, C. ruber) whose ranges are relatively more restricted. Furthermore, in several cases, the distributions of subspecies were not congruent with our molecular information. We suggest regional conservation perspectives for southwestern deserts cannot rely upon subspecies as biodiversity surrogates, but must instead employ a molecular and deep historical perspective as a primary mechanism to frame biodiversity reserves within this region.
A preliminary analysis of phylogenetic relationships and biogeography of the dangerously venomous Carpet Vipers, Echis (Squamata, Serpentes, Viperidae) based on mitochondrial DNA sequences.
Amphibia-Reptilia 30(2):273-282. DOI: 10.1163/156853809788201090.
Phylogenetic analysis of 1117 bp of mitochondrial DNA sequences (731 bp of cytochrome b and 386 bp of 16S rRNA) indicate that Echis consists of four main clades: E. ocellatus, and the E. coloratus, E. pyramidum, and E. carinatus groups. In the E. coloratus group, E. coloratus itself shows substantial genetic divergence from E. omanensis, corroborating their separate species status. In the E. pyramidum clade, E. pyramidum from Egypt and E. leucogaster from West Africa are genetically very similar, even though samples are separated by 4000 km. South Arabian populations of the E. pyramidum group are much better differentiated from these and two species may be present, animals from Dhofar, southern Oman probably being referable to E. khosatzkii. In the E. carinatus group, specimens of E. carinatus sochureki and E. multisquamatus are very similar in their DNA. The phylogeny indicates that the split between the main groups of Echis was followed by separation of African and Arabian members of the E. pyramidum group, and of E. coloratus and E. omanensis. The last disjunction probably took place at the lowlands that run southwest of the North Oman mountains, which are likely to have been intermittently covered by marine incursions; they also separate the E. pyramidum and E. carinatus groups and several sister taxa of other reptiles. The E. carinatus group may have spread quite recently from North Oman into its very extensive southwest Asian range, and there appears to have been similar expansion of E. pyramidum (including E. leucogaster) in North Africa. Both these events are likely to be associated with the marked climatic changes of the Pleistocene or late Pliocene. Similar dramatic expansions have also recently occurred in three snake species in Iberia.