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of the real lizards, family Lacertidae
Teira dugesii selvagensis BISCHOFF, OSENEGG & MAYER, 1989
Aguilar, F.F. de (2016) -
The Madeira wall lizard, Teira dugesii selvagensis, is a partially herbivorous species that also predates Cory shearwater chicks, having an impact of 5% on the reproductive success of this seabird at the island of Selvagem Grande. This study aims to characterize and compare the population structure of Madeira wall lizards, as well as its role in the trophic web of various areas of Selvagem Grande. These areas were designated according to the type of relief, size of seabird colonies and vegetation cover, in two different Cory shearwater nesting seasons (egg incubation and offspring feeding period). The abundance of lizards in different areas and in both seasons was estimated using capture-mark-recapture. Lizard droppings were also collected, to identify contents. Samples of species belonging to the Selvagem Grande trophic chain were collected for isotopic analysis. Isotopic results were analyzed using SIAR and SIBER packages. Both the highest abundance of lizards and the highest vegetation cover were found in areas with small seabirds colonies. In spite of that, the proportion of lizard immatures was higher on the South/Southwest facing cliffs, where the largest seabird colonies are located. Herbivory increases with lizard size, and there was a high percentage of vegetable contents (about 65%) in the droppings. The isotopic basis of the trophic chain varied significantly among areas and is probably influenced by island topography and seabird inputs. Comparing signatures between geckos and lizards of the island, allowed the characterization of niches occupied by each species, being the differences justified by their diets. In areas with larger seabird colonies, seabirds or nutrient inputs brought by them were extremely important for the diet of T.d. selvagensis. The lizards with smaller differences in their isotopic niche between seasons were found in the areas with most seabirds, while the highest isotopic niche differences occured where resources were fewer. Isotopic results validate the dropping analysis, indicating consumption of seabirds during the bird offspring feeding period. Results obtained in this study suggest that the pressure of lizards on seabirds colonies is variable along the island. In contrast to what was expected, in areas with more vegetation there was a reduced impact on seabirds, despite higher abundances of lizards. Lizard monitorization should be continued to assess population trends as vegetation recovers after the eradication of rabbit and domestic mouse.
Bischoff, W. (1996) -
New informations concerning systematical questions within the family Lacertidae, which were published during the last year, are presented.
Bischoff, W. (1998) -
Das kleine »Galapagos vor der europäischen Haustür« ist Gegenstand dieses in sich geschlossenen Bandes. Er gibt erstmalig einen Überblick über die Herpetofauna dieser Inselgruppen.
Bischoff, W. & Osenegg, K. & Mayer, W. (1989) -
In this study 175 specimens of Podarcis dugesii from the islands Madeira, Deserta Grande, Bugio, Porto Santo, Selvagem Grande and Selvagem Pequena were examined. Morphological data from lizards of these six islands were subjected to a Variance- and Discriminant-analysis and compared to results from an Enzyme-Electrophoresis. Podarcis dugesii mauli is placed as a synonym of the nominate subspecies. In contrast, two new subspecies are described: Podarcis dugesii jogeri ssp.n. for the population from Porto Santo and Podarcis dugesii selvagensis ssp.n. from the Selvagens islands.
Böhme, W. (2010) -
In the herpetological collection of ZFMK 528 scientific species group names are represented by type materi- al. Of these, 304 names are documented by primary type specimens (onomatophores) while for 224 further names sec- ondary type specimens (typoids) are available, ranging chronologically from 1801 to 2010. The list is a shortened pred- ecessor of a comprehensive type catalogue in progress. It lists name bearing types with their catalogue numbers includ- ing information on further type series members also in other institutions, while secondary types are listed only by pres- ence, both in ZFMK and other collections including holotype repositories. Geographic origin and currently valid names are also provided.
Brehm, A. & Harris, A.D.J. & Alves, C.D. & Jesus, J.D. & Thomarat, F.D. & Vicente, L.D. (2003) -
We sequenced the complete control region (CR) and adjacent tRNAs, partial 12S rRNA, and cytochrome b (over 3100 bp) from eight individuals of Madeiran wall lizards, Lacerta dugesii, from four distinct island populations. The tRNAs exhibit a high degree of intraspecific polymorphisms compared to other vertebrates. All CR sequences include a minisatellite that varies in length between populations but is apparently fixed within them. Variation in minisatellite length appears between populations separated by apparently very short evolutionary time spans. Many motifs identified in the CR of other vertebrates are not highly conserved, although conserved blocks are identifiable between the few published reptile CR sequences. Overall there are extensive differences in the internal organization of the reptile CR compared to the more widely studied mammals and birds. Variability in the CR is lower than in cytochrome b, but higher than in 12S rRNA. Phylogenetic analysis of these sequences produces a well-resolved estimate of relationships between populations.
Brehm, A. & Jesus, J. & Spinola, H. & Alves,C. & Vicente, L. & Harris, D.J. (2003) -
Partial sequences from two mitochondrial DNA genes, cytochrome b and 12S rRNA, were used to assess the phylogenetic re- lationships of populations of Lacerta dugesii from the volcanic Atlantic islands of Madeira, the Desertas, Porto Santo, and the Selvagens. All four-island groups are genetically distinguishable and populations within each contain similar degrees of genetic diversity. Molecular clock estimates suggest that the islands were colonized much later after their emergence compared to other Atlantic islands, possibly due to their greater geographical isolation. Mismatch analysis of all populations is consistent with ex- ponential growth, as expected after colonization of empty niches. The Selvagens contain genetic substructuring between the islets.
Jesus, J. & Brehm, A. & Harris, D.J. (2005) -
Jesus, J. & Sampaio, L. & Crespo, E. (2006) -
Jesus, J. & Teixeira, S. & Teixeira, D. & Freitas, T. & Russo, D. (2009) -
Jesus, J.M. Abreu de (2005) -
Partial sequences of mitochondrial DNA genes (12S rRNA, 16S rRNA and Cytochrome b) and nuclear DNA (c-mos and enolase), as well as enzymatic markers were used to infer colonization patterns and genetic relationships of reptiles from families lacertidae, scincidae and gekkonidae of Madeira, Cape Verde Archipelagos and Gulf of Guinea islands. These markers also allowed us to uncover species introductions in these islands. The data allows us to detect a intra-specific geographical structure on Mabuya maculilabris from São Tomé and a inter-specific geographical structure of the genus Mabuya in Cape Verde Archipelago. It is also possible to detect a well defined intra-specific geographical structure in Lacerta dugesii from the Archipelago of Madeira that presents fixed haplotypes for each of the four groups of islands. Lacerta dugesii has probably been the result of one single colonization event in the Archipelago of Madeira. Our results reject the hypothesis of the anthropological introduction of the species in the Selvagens Islands. Mabuya spp. from Cape Verde islands were also the result of one colonization event followed by a radiation through the islands. Our results from Cape Verde, and data from reptiles endemic to the Canary Islands, suggest that the number of colonization events of skinks is lower than that observed in geckos. Our results from the Gulf of Guinea seems to be an exception to this rule. Mabuya spp. is the result of four different colonization events, one for Mabuya ozorii of Annobon, one for Mabuya affinis of Príncipe and two for the two forms of Mabuya maculilabris (one from Príncipe and one from São Tomé). Probably the two forms of São Tome and Príncipe are different species or belong to a species complex. The geckos from the Gulf of Guinea islands are the result of fewer events of colonization, probably two for Hemidactylus spp. Considering the genus Mabuya we consider five groups of species, one more than the previously published data, that is the North Africa + Turkey group which implies the need to divide the forms of Africa. Using Lacerta dugesii as a model we didn’t find congruence between enzymatic, morphological and molecular data. The molecular markers allow us to detect introduced species as Hemidactylus mabouia in Madeira, Cape Verde and islands of Gulf of guinea islands, as well as Ramphotyphlobs braminus in Annobon. It was also possible to review the taxonomic status of some species. We consider the existence of three subspecies of Lacerta dugesii. In Mabuya from Cape Verde Islands, the previous established relationships are also validated. In Tarentola more genetic distinct groups than those previously established were obtained, and probably we discovered a new subspecies of Tarentola gigas. We confirmed the presence of a Mabuya in Annobon (probably M. ozorii, omitted species on EMBL Reptile database). Two distinct forms of Mabuya maculilabris were found, one in Príncipe and one in São Tomé. The molecular data seems to reject the anthropological introduction of M. maculilabris. The c-mos can be a good phylogenetic marker at the infraspecific level. The same happened for the control region which is. At least in Lacerta dugesii, less variable than cytochrome b.
Malkmus, R. (2002) -
Matias, R. & Rebelo, R. & Granadeiro, J.P. & Catry, P. (2009) -
Reptiles are uncommon as seabird predators on islands. While conducting a study on Cory`s Shearwaters (Calonectris diomedea) on Selvagem Grande, North Atlantic, incidental observations during 2006 early hatching period indicated that some chicks were being killed by Madeiran Wall Lizards (Teira dugesii). In the same year and in 2007, the phenomenon was further examined and samples of 78 and 153 nests, respectively, were followed. Also, non-systematic visits were made to other nests. A total of 40 episodes of lizards depredating Cory`s Shearwaters hatchlings was recorded. This hitherto unknown source of predation for this shearwater accounted for the failure of four (5.1%) study nests in 2006 and eight (5.2%) study nests in 2007. All recorded predation cases took place either during or shortly after hatching. Also, non-systematic observations indicated that three other species of burrowing petrels (Bulwer`s Petrel, Bulweria bulwerii; Madeiran Storm-petrel, Oceanodroma castro, White-faced Storm-petrel, Pelagodroma marina) were preyed upon by Madeiran Wall Lizards. Predation by lizards is apparently a phenomenon of lesser concern for Cory`s Shearwaters but the potentially higher impact over the smaller petrel species is not known.
Sadek, R.A. (1981) -
The gut contents of about 1700 lizards from the Madeiran Archipelago and die Salvage Islands were examined. The diet, which shows habitat and geographical variation, consists of a variety of invertebrates and a good amount of plant matter. The degree of herbivory is correlated widi lizard sex and size and widi tail autotomy. The amount of food and specialization in the diet were also correlated. Comparisons are made between die sex-size classes widiin die populations.
Silva-Rocha, I. & Sá-Sousa, P. & Fariña, B. & Carretero, M.A. (2016) -
Wagner, P.R. (2002) -
Im August letzten Jahres führte mich eine wissenschaftliche Exkursion zusammen mit Herrn Prof. PUTZER, Duisburg auf den Selvagens Archipel. Zweck der Reise waren Untersuchungen der Bioakkumulation gammastrahlender Radionuklide an marinen und terrestrischen Organismen und herpetologische Untersuchungen an den dort endemischen Teira dugesii selvagensis und Tarentola bischoffi. Da bisher kaum bekannt, sollten den Lesern der „elaphe“ hier die Inseln und ihre Echsen näher vorgestellt werden.
Wagner, P.R. (2004) -
Freilandbeobachtungen an Teira dugesii selvagensis während zweier Forschungsreisen auf den Ilhas Selvagens in den Jahren 2001 und 2002 werden vorgestellt und mit allgemeinen Informationen über Teira dugesii auf die Inseln ergänzt.