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Dieser Beitrag ist der erste Teil einer Serie über die Herpetofauna der Kanarischen Inseln, in dem es zunächst auf die Lage, das Alter und die Entstehung des Archipels eingegangen wird. Bemerkungen zur Topographie, zum Klima und zur Vegetation geben Hinweise auf die Umweltbedingungen für die hier lebenden Amphibien und Reptilia. Herkunft und gegenwärtige Situation der endemischen Arten werden diskutiert, und es folgen Bemerkungen zu den nur fossil bekannten Arten Testudo burchardi, Gallotia goliath und G. maxima: Folgende Arten wurden auf den Inseln eingeschleppt: Hyla meridionalis, Rana perezi, Chamaeleo chamaeleon, Hemidactylus turcicus und Tarentola mauritanica. Den Abschluß dieses Beitrages bildet ein Schlüssel zum Bestimmen aller gegenwärtig von den Kanarischen Inseln bekannten Arten und Unterarten.

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Das kleine »Galapagos vor der europäischen Haustür« ist Gegenstand dieses in sich geschlossenen Bandes. Er gibt erstmalig einen Überblick über die Herpetofauna dieser Inselgruppen.

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Vocalizations of the Iberian lacertids Psammodromus algirus and P. hispanicus as well as of the Canarian endemic Gallotia atlantica, G. galloti galloti, g. eisentrauti, G. caesaris, g. gomerae, g. palmae and G. stehlini were analyzed sonagraphically. The structure of the calls resembles those known from the families Pygopodidae (Lialis, Delma) and Iguanidae (Anolis) rather than those of Gekkonidae. The vocal repertoire of the lacertids is rather simple; it consists of clicks and various combinations of tonal and noisy components. Duration and frequency range of the sounds are variable; at least frequency range seems to vary with individual size, body temperature and the level of excitement. Most lizards vocalized when handled, but vocalization was also heard in free-ranging animals kept in cages and observed in the field. Sounds are uttered by inferior individuals defending a hide but also by dominant animals pursuing a rival. Field observations indicate that vocal activity is most intensive after sunset and may last until midnight. It is argued that vocalization in the highly territorial lizards of genus Gallotia may help regulate the high population densities, especially in the dark when optical signals do not work. The subtropical climate and the heat-gathering lava of the Canary islands make a nocturnal activity possible. The systematic significance of vocalization in Gallotia is discussed. Vocalization may be a synapomorphic character defining the genus Gallotia, but it is also present in Psammodromus and has been mentioned for Podarcis, Lacerta and Ichnotropis. From this, a multiple evolution can also not be excluded. Therefore, the common derived karyotype of the Gallotia species is the only established synapomorphic character justifying a separate generic but not at all familial rank for the Canary lizards.

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Phylogenetic relationships among species and subspecies of the Canary Island endemic lizard genus Gallotia are inferred base on nucleotide sequence of fragments of 12S ribosomal RNA and cytochrome b mitochondrial genes. The four morphologically established species have also been recognized at the molecular level. Relative affinities among species follow an eatsern-western geographic transect. The nearly extinct species Galloti simonyi from the most western island of El Hierro is closely related to the common western species Gallotia galloti. The nearest branch to this pair is Gallotia stehlini from the central island of Gran Canaria, and finally, Gallotia atlantica from the two eastern and geologically oldest islands appears as the most distantly related species of the group. At the statistical level, four subspecies can be recognized in G. galloti, but only two in G. atlantica.

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All recent members of the genus Gallotia from the seven large isles of the Canary Archipelago have been investigated immunologically by means of micro-complement- fixation technique. Three species of genera living in NW-Africa were used as outgroup. Prom the evolutionary tree constructed from the results isolation times can be estimated and ways of colonization can be reconstructed. Various possibilities of insertion of the fossil species G . goliath in the evolutionary tree are discussed.

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We present data to confirm that the island of La Palma harbours the first established feral population of ferrets Mustela furo on the Canary Islands in the Atlantic Ocean. It is not known when the species was introduced but individuals occasionally lost during hunting appear to have become established sometime in the previous 2 decades. Sightings of ferrets are mainly in the north of the island but they are likely to expand their range southwards, and a few have already been detected in the centre of the island. We report a total of 45 cases of wild ferrets in 28 different localities during 1998–2007. To minimize effects on native species, control measures or eradication are required. Public awareness of the problem and education campaigns, especially among hunters, are needed to reduce the threat of this alien species to the biota of the Canary Islands.

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Several behaviour patterns that appear during courting of females by male lizards are described for two different Canarian subspecies: Gallotia galloti eisentrauti and G. galloti palmae. A report of copulation in G.galloti caesaris is also included. The importance of the courting behaviour as a character for studying behaviour evolution and taxonomic relationships is discussed in relation to another behavioural character previously cited by other authors.

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The aim was to study as to how biometric and life-history traits of endemic lacertids in the Canary Islands (genus Gallotia) may have evolved, and possible factors affecting the diversification process of this taxon on successively appearing islands have been deduced. To that end, comparative analyses of sexual dimorphism and scaling of different body, head and life-history traits to body size in 10 species/subspecies of Gallotia have been carried out. Both Felsenstein`s independent contrasts and Huey and Bennett`s `minimum evolution` analyses show that male and female snout-vent length (SVL) changed proportionally (sexual size dimorphism not changing with body size) throughout the evolution of these lizards and all within-sex biometric traits have changed proportionally to SVL. Life-history traits (size at sexual maturity, clutch size, hatchling SVL and mass, and life span) are highly correlated with adult female body size, the first two being the only traits with a positive allometry to female SVL. These results, together with the finding that the slope of hatchling SVL to female SVL regression was lower than that of SVL at maturity to female SVL, indicates that larger females reach maturity at a larger size, have larger clutches and, at the same time, have relatively smaller hatchlings than smaller females. There was no significant correlation between any pair of life-history traits after statistically removing the effect of body size. As most traits changed proportionally to SVL, the major evolutionary change has been that of body size (a ca. threefold change between the largest and the smallest species), that is suggested to be the effect of variable ecological conditions faced by founder lizards in each island.

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A parasitological survey has been carried out to determine the relationships between host diet and parasite fauna. Diet, and infracommunities and component communities of two subspecies of lacertid lizards, Gallotia galloti galloti (Oudart, 1839) and G. g. palmae (Boettger et Müller, 1914) from Tenerife and La Palma islands (Canary Islands, Spain), have been analysed. High values of parasite infection parameters were found in both subspecies, which were only infected by nematodes of the family Pharyngodonidae. Plant matter was mainly consumed by both lizard subspecies and relevant amounts of mineral matter were also found in both hosts. Diet of these lacertid lizards was correlated with their parasite fauna formed by monoxenous nematodes parasitising herbivorous reptiles, as in tortoises and iguanid lizards. Abundance and richness of parasites increased with consumption of plant matter in G. g. galloti. Helminthological data support the idea of a tendency of both hosts towards herbivory, probably related to their own phylogeny linked to insularity.

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A field study was performed to evaluate the effect of exposure to organophosphorus (OP) and carbamate (CB) pesticides on the lizard Gallotia galloti palmae. Butyrylcholinesterase (BChE) activity was measured in the plasma of 420 lizards collected from agricultural and reference areas on the Island of La Palma (Canary Islands, Spain) in two sampling periods. Exposure to cholinesteraseinhibiting pesticides was evaluated by a statistical criterion based on a threshold value (two standard deviations below the mean enzyme activity) calculated for the reference group, and a chemical criterion based on the in vitro reactivation of BChE activity using pyridine- 2-aldoxime methochloride (2-PAM) or after water dilution of the sample. Mean (GSD) BChE activity for lizards from agricultural areas was significantly lower (Fuencaliente site=2.00G0.98 mmol min_1 ml_1, Tazacorte site=2.88G1.08) than that for lizards from the reference areas (Los Llanos site=3.06G1.17 mmol min_1 ml_1, Tigalate site=3.96G1.62). According to the statistical criterion, the number of lizards with BChE depressed was higher at Fuencaliente (22% of males and 25.4% of females) than that sampled at Tazacorte (7.8% of males and 6.2% of females). According to the chemical criterion, Fuencaliente also yielded a higher number of individuals (112 males and 47 females) with BChE activity inhibited by both OP and CB pesticides. CBs appeared to be the pesticides most responsible for BChE inhibition because most of the samples showed reactivation of BChE activity after water treatment (63.3% from Fuencaliente and 29% from Tazacorte). We concluded that the use of reactivation techniques on plasma BChE activity is a better and more accurate method for assessing field exposure to OP/CB pesticides in this lizard species than making direct comparisons of enzyme activity levels between sampling areas.

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Die Kanareneidechsen der Gattung Gallotia gehören zu den chasrismatischten Vertretern der Lacertidae. Durch ihr Vorkommen auf den beliebten Urlaubsinseln, ihre Größe und ihr teils massenhaftes Auftreten sind sire auch bei Laien recht bekannt, während die packenden bis dramatischen Geschichten rund um die beinahe ausgestorbenen Rieseneidechsen die Fachleute elektrisieren. Im seltsamen Mißverhältnis dazu steht, dass diese kräftigen, teils farbenfrohen Echsen in der letzten Zeit in der Terraristik nur noch wenig beachtet worden sind. Zeit für eine Ehrenrettung!

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Illustrated by specimens of Gallotia galloti palmae from the south and northwest of the Canary Island La Palma the noticeable colour adaptation to their habitat is documented. We assume that these colourations are the result of selective pressure.

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During two holiday stays (27.9.–11.10.2016 and 05.03.–12.03.2017) on the Canary Island of La Palma we undertook some herpetological photo excursions. The high variability of the lizard Gallotia galloti palmae was particularly impressive. With the following selection of photographs, which also includes pictures from the south of La Palma made in 2005, we would like to present the interesting herpetofauna as well as the landscape of the island that is full of contrast.

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Lizards from the Canary Islands may act as pests of several cultivated plants. As a case in point, vineyard farmers often complain about the lizards’ impact on grapes. Though no specific pesticide is used for lizards, several pesticides are used in vineyards to control for insects, fungi, etc. We therefore tested whether lizards (Gallotia galloti palmae) could detect and discriminate pesticide-treated from untreated grapes. To answer this question, we performed experiments with adults of both sexes obtained from three localities in La Palma Island. Two of them were a vineyard and a banana plantation that had been treated with pesticides and the other one was in a natural (untreated) site. In the laboratory, lizards were offered simultaneously one untreated (water sprayed) and one treated (with Folithion 50 LE, diluted to 0.1%) grape placed on small plates. The behaviour of the lizards towards the fruits was filmed and subsequently quantified by means of their tongue-flick, licks or bite rates to each of the grapes. Results showed that only lizards from the natural (untreated) site clearly differentiated the two types of grapes, performing significantly more tongue-flicks, licks and bites to the untreated than to the pesticide-treated grapes. Lizards captured at the other two sites (cultivated fields with pesticide treatment), did not show a signifi-cantly different response to the two types of grapes. These results suggest that lizards living in or near cultivated fields may be habituated to pesticide-treated food and, therefore, do not clearly discriminate treated from untreated food items. However, another possibility is that natural selec-tion (or maybe resistance) could be responsible by these individuals in the populations showing this kind of pesticide insensitiveness.