Zur Haltung und Fortpflanzung des Wickelskinks Corucia zebrata GRAY, 1855.

SALAMANDRA 27 (4): 238-245.

Zusammenfassung:

Es wird von der Pflege und Nachzucht des lebendgebärenden Wickelskinks Corucia zebrata über einen Zeitraum von 6 Jahren berichtet. Von 1986 bis 1990 wurden von 7 Weibchen 22 Jungtiere geboren, davon 6 Zwillinge und 10 Einzeltiere. Die Wickelskinke werden bei einer Durchschnittstemperatur von 25 °C gehalten, suchen aber oft den Strahlungsbereich von Quecksilberdampf-Hochdrucklampen mit einer Temperatur von 28-34 °C auf. Ein Moos-Bodenbelag und tägliches Aussprühen des Behälters sorgen für eine Luftfeuchtigkeit von 60-80 %. Dabei kann Wasser aufgeleckt, außerdem aber einem Bodennapf entnommen werden. Diese Tiere ernähren sich herbivor, vorwiegend von Früchten, Gemüse und Salat, die mit Vitamin-Kalkpulver anzureichern sind. Bei der Paarung schiebt das Männchen den Genitalbereich unter das sich seitlich anhebende Weibchen und gelangt so abgedreht zur Vereinigung. Die Trächtigkeit dauert circa 6 Monate, und die Weibchen bringen in Abständen von 10-12 Monaten jeweils 1 bis 2 Junge zur Welt. Die Jungtiere können bei den Eltern verbleiben und werden von diesen gegen Störenfriede und Angreifer verteidigt. Die Tiere der Gruppen A (Malaita) und B (Bougainville) unterscheiden sich in morphologi-schen Merkmalen, Färbung und Verhalten. Das wirft die Frage auf, ob es sich um verschiedene Unterarten handelt.

schmidt-biblio

STOW, A. J. & SUNNUCKS, P. (2004a)

High mate and site fidelity in Cunningham's skinks (Egernia cunninghami) in natural and fragmented habitat.

Molecular Ecology 13 (2): 419-430. 10.1046/j.1365-294X.2003.02061.x

Abstract:

While habitat alteration has considerable potential to disrupt important within-population processes, such as mating and kin structure, via changed patterns of dispersal, this has rarely been tested. We are investigating the impact of anthropogenic habitat alteration on the population biology of the rock-dwelling Australian lizard Egernia cunninghami on the Central Tablelands of New South Wales, Australia, by comparing deforested and adjacent naturally vegetated areas. The novel analyses in this paper, and its companion, build on previous work by adding a new replicate site, more loci and more individuals. The additional microsatellite loci yield sufficient power for parentage analysis and the sociobiological inferences that flow from it. Genetic and capture–mark–recapture techniques were used to investigate mate and site fidelity and associated kin structure. Analyses of the mating system and philopatry using 10 microsatellite loci showed high levels of site fidelity by parents and their offspring in natural and deforested habitats. Parentage assignment revealed few individuals with multiple breeding partners within seasons and fidelity of pairs across two or more breeding seasons was typical. Despite reduced dispersal, increased group sizes and significant, dramatic increases in relatedness among individuals within rock outcrops in deforested areas, no significant differences between deforested and natural areas were evident in the degree of multiple mating or philopatry of breeding partners within and across seasons. With the exception that there was a significantly higher proportion of unmated males in the deforested area, the social and mating structure of this species has so far been surprisingly robust to substantial perturbation of dispersal and relatedness structure. Nonetheless, approximately 10-fold elevation of mean pairwise relatedness in the deforested areas has great potential to increase inbred matings, which is investigated in the companion paper.

STOW, A. J. & SUNNUCKS, P. (2004b)

Inbreeding avoidance in Cunningham's skinks (Egernia cunninghami) in natural and fragmented habitat.

Molecular Ecology 13 (2): 443-447. 10.1046/j.1365-294X.2003.02060.x

Abstract:

Habitat fragmentation/alteration has been proposed as a distinct process threatening the viability of populations of many organisms. One expression of its impact may be the disruption of core population processes such as inbreeding avoidance. Using the experimental design outlined in our companion paper, we report on the impact of habitat alteration (deforestation) on inbreeding in the rock-dwelling Australian lizard Egernia cunninghami. Ten microsatellite loci were used to calculate relatedness coefficients of potential and actual breeding pairs, and to examine mate-choice and heterozygosity. Despite significantly less dispersal and higher within-group relatedness between potential mates in deforested than in natural habitats, this did not result in significantly more inbred matings. Average relatedness amongst breeding pairs was low, with no significant difference between natural and fragmented populations in relatedness between breeding pairs, or individual heterozygosity. Active avoidance of close kin as mates was indicated by the substantially and significantly lower relatedness in actual breeding pairs than potential ones. These facts, and heterozygote excesses in all groups of immature lizards from both habitats, show that E. cunninghami maintained outbreeding in the face of increased accumulation of relatives.

Integrative Approaches to the Systematics and Conservation of the Reptiles of the Cape Verde Islands.

PhD Thesis. Departamento de Biologia Faculdade de Ciências da Universidade do Porto

Volltext: http://www.scvz.org/pdf/TeseRVLowRes_ii.pdf

Summary:

Two of the main sensitivities of Conservation Biogeography are the inadequacies in taxonomic and chorological data, the so-called Linnean and Wallacean shortfalls, respectively. These shortfalls increase in the more remote areas such as oceanic islands. This thesis contributed to dilute those shortfalls in one of those remote areas, the Cape Verde Islands, for one of its least studied group, the reptiles.The specific goals of this thesis were related to answering to what diversity occurs there and to address putative biogeographic factors that explain why diversity is unevenly distributed. Then, it is aimed to answer where this biodiversity can be found and, based on all the gathered data, to plan how to better protect it at different levels.

First, the phylogeographic patterns of terrestrial reptiles were studied to identify an introduced agamid and cryptic endemic taxa of the three genera (Hemidactylus, Tarentola and Chioninia) and to clarify their systematics. The new introduced taxon in Cape Verde was identified as Agama agama. Also, some endemic subspecies were upgraded to the specific status and three new cryptic species (Hemidactylus lopezjuradoi, Tarentola bocageiand T. fogoensis) and subspecies (Chioninia vaillanti xanthotis, C. spinalis boavistensis and C. s. santiagoensis) were described using an integrative approach combining morphological, genetic and population analyses. These studies highlighted the usefulness of integrative datasets in the fields of Taxonomy and Phylogeography and how they can improve the performance of taxa estimations. In addition, the origin of the introduced Agama and the colonisation patterns of the endemic taxa were inferred and several historical and environmental factors, such as the Pleistocene sea-level falls and altitude, were related with the uneven distribution of diversity at intraspecific level. Low intraspecific divergence between reptile lineages of the same island has been explained by the recent volcanic activity and high ecological stress that could lead to population extinctions, and the low habitat diversity within some islands that could restrain opportunities for allopatric diversification.

Secondly, extensive sampling and bibliographic chorological data were compiled to produce and updated distribution atlas for all taxa addressing doubtful or erroneous records and to develop predictive maps of occurrence based on ecological niche-based models for most of the endemic taxa. This data also allowed the detection of the wide-spreading of the introduced H. angulatus in Santiago and Boavista and the colonisation of two new islands by the exotic H. mabouia. In addition, it allowed updating the conservation status for the endemic taxa showing that around half of them are threatened under the IUCN criteria and that the most frequent classifying criterion was related to restricted geographic range. The most pervasive threats identified are related to natural disasters, as droughts and volcanic activity, intrinsic factors, such as low population densities and restricted range, and introduced species.

Finally, this work also demonstrated how ecological niche-based models are useful tools to infer ranges on relatively under-sampled and remote areas with high accuracies and how they can be applied to conservation, maximizing efficiency of reserve designs. Results depicted that in Santa Luzia, Branco, Raso, Sal, Boavista, Maio and Rombos designation of new protected areas is not a priority since the ones that are going to be implemented will reach the conservation targets for all identified evolutionary significant units of those islands and islets. On the other hand, new or modified reserves should be implemented on the remaining islands to cover all identified lineages of Cape Verdean reptiles. This measure is especially important in Fogo and Brava, where no planning unit selected by the area prioritisation scenarios is within the protected areas limits and no protected area is planned, respectively.
Altogether, this work exemplifies the usefulness of integrating different disciplines to more effectively allowing systematic conservation planning of biodiversity.

A review of the African red–flanked skinks of the Lygosoma fernandi (BURTON, 1836) species group (Squamata: Scincidae) and the role of climate change in their speciation.

Zootaxa 2050: 1–30. ISSN 1175-5326.

Abstract:

We present an analysis of the morphometric and genetic variability of Lygosoma fernandi. Geographical variation and taxonomic consequences are discussed and Lepidothyris Cope, 1892 is resurrected as genus for the L. fernandi species group. The results show that Lepidothyris fernandi sensu lato is a species complex, which comprises an eastern and a western species. Each of them has a further subspecies of its own, and a third distinct species is present in southwestern Central Africa. The morphological and genetic differences between these taxa are analyzed resulting in the description of two new taxa, and the resurrection of two more taxa.