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of the real lizards, family Lacertidae
Gallotia caesaris (LEHRS, 1914)
Acosta, P.F. & Molina-Borja, M. (2016) -
Se describe un comportamiento previamente no observado en el lagarto de Boettger (Gallotia caesaris). Varios ejemplares de la subespecie G. caesaris caesaris se subieron al dorso de un águila pescadora (Pandion haliaetus) y comieron allí moscas parásitas (Diptera, Hippoboscidae) que estaban sobre las plumas; el águila pescadora se hallaba en un nido situado en la costa del mar de las Calmas en la isla de El Hierro. Este comportamiento es otro caso de mutualismo (simbiosis de limpieza) ya que puede contribuir a mejorar la salud de las águilas pescadoras y, por otra parte, es un suplemento alimenticio para los lagartos.
Albaladejo, G. (2016) -
Arechavaleta, M. & S. Rodríguez & N. Zurita & A. García (coord.) (2010) -
Báez, M. (1984) -
Bannert, B. (1998) -
The longevity of several lacertid lizard species in captivity is reported. The conditions of keeping, which have been successful throughout many years, are briefly presented.
The lizard species Gallotia atlantica, G. caesaris, G. galloti eisentrauti, and G. stehlini from the Canary Islands and Teira dugesii from Madeira were kept and bred in captivity. Since ecological data concerning the breeding biology of these species are rare, the results of several years of captive breeding are presented. Data were collected from six pairs of G. atlantica during five years. The females laid 1-3 clutches of eggs each year between April and the beginning of September. The first egg clutches of a year contained 2.7 (1-5) eggs and the second egg clutches consisted of 2.5 (1-4) eggs. Third egg clutches were rare and consisted of only 1.7 (1-2) eggs. The baby lizards hatched after 73 (64-87) days. Three pairs of G. caesaris were observed during three years. Between the middle of May and the end of July the females of this species laid one clutch per year containing 3.8 (3-5) eggs. Only one female produced a second clutch during one season. The young hatched after 67 (64- 69) days. Eight pairs of G. g. eisentrauti were observed during seven years. Between the beginning of May and the end of August these females oviposited annually 1-2 clutches, which contained 4.7 (2-9) eggs in the first clutch of a year and 3.4 (2-6) eggs in the second annual clutch. The young hatched after 73 (62-89) days. One pair of G. stehlini was observed over a period of six years. Between June and August this female produced annually one clutch containing 9.8 (5-14) eggs. The young hatched after 80 (75-86) days. Two pairs of Teira dugesii were observed during one year and two pairs during four years. Between the end of April and the middle of August the females produced 1-2 clutches per year with 2.6 (2-3) eggs in the first and 2.1 (1-3) eggs in the second clutch of a year. The incubation period of the eggs was 72 (59-93) days. Furthermore, sizes of hatchlings of all species are presented. Colour patterns of hatchlings of G. g. eisentrauti, G. caesaris, and G. atlantica are described. Observations concerning the raising of the young in captivity are reported.
Bannert, B. & Lux, E. & Sedlaczek, J. (1995) -
The lizards of the genus Gallotia, which are endemic to the Canary Islands, are studied for their endo- and ectoparasites. The island-dwelling omnivorous lizards harbor protozoan parasites of the genus Sarcocystis which reveal an unusual cannibalistic mode of transmission. Haemogregarine blood parasites of as yet undetermined taxonomic status have recently been found in three Gallotia-species. An undescribed bloodsucking mite of the genus Ophionyssus, which was found on G. galloti from Tenerife, is suspected to be involved in the life cycle on the protozoan blood parasites. Further investigations on the presented parasites concerning their taxonomy, morphology, biology, and ecology are necessary.
Barahona, F. (1998) -
Barbadillo, L.J. & Lacomba, J.I. & Pérez-Mellado, V. & Sancho, V. & López-Jurado, L.F. (1999) -
Beyhl, F.E. (1997) -
Bischoff, W. (1985) -
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.
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. & Nettmann, H.-K. & Rykena, S. (1979) -
Review of the herpetofauna of the island of Hierro, where the following species occur: Hyla meridionalis, Rana perezi, Tarentola delalandii ssp., Chalcides viridanus ssp., Gallotia simonyi, and Gallotia galloti caesaris. T. delalandii, C. viridanus, and G. galloti caesaris were captured. Data concerning habits and distribution are presented. It is likely that T. delalandii and C. viridanus represent subspecies characteristic for Hierro. Variation of certain characters in G. galloti caesaris is correlated with its vertical distribution. In some localities this species is extremely abundant. Unfortunately, the large and endangered G. simonyi was not observed. Chances of its survival are discussed. Activities to preserve this lizard from extinction are suggested.
Boettger, C.R. & Müller, L. (1914) -
Böhme, W. & Hutterer, R. & Bings, W. (1985) -
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.
Boulenger, G.A. (1920) -
Bowler, J. (2018) -
Bravo, T. (1954) -
Caetano, A. & Cejudo, D. & Garcia-Marquez, M. & Orrit, N. & Romero, M. (1997) -
Carretero, M.A. & Martínez-Solano, Í. & Ayllón, E. & Llorente, G. (2018) -
Castanet, J. & Báez, M. (1991) -
A sub-fossil deposit located in Hierro Island (“Playa de la Arena”) at the beginning of the Middle Ages, displays among other animals, bones of lizards. According to bone histological criteria, it can be determined that two species of lizards are present in this deposit. Bones of various sizes come from a large sized species, probably Gallotia simonyi. The oldest specimen observed in our sample was at least 14 years old. Other bones come from lizards of little size, probably G. g. caesaris. The oldest specimen collected was 6 or 7 years old.
Castilla, A.M. & Van Damme, R. & Bauwens, D. (1999) -
We discuss three aspects of the thermal biology of lacertid lizards. First, we provide an overview of the available data on field body temperatures (Tb), the thermal sensitivity of various performance functions and selected body temperatures in different species of lacertid lizards. We also briefly summarise information on the mechanisms of thermoregulation. Second, we discuss recent developments to estimate the »precision« of thermoregulation, and the contribution of distinct behavioural mechanisms. Finally, we revise available evidence for the existence of evolutionary adjustments of thermal characteristics in lacertid lizards. Existing studies have mainly dealt with within- and among-species differences in thermoregulatory behaviour (selected temperatures) and thermal physiology of adults (optimal temperatures, heating rates). Available data provide only limited evidence for clear-cut evolutionary shifts in thermal physiology characteristics along climatic gradients.
Cejudo, D. & Bowker, R.G. & Márquez, R. (1999) -
One of the numerous factors suggested for the decline of the giant lizard of El Hierro (Gallotia simonyi) is the competition with the smaller congener, G. caesaris, ubiquitous throughout El Hierro. Experiments were conducted to determine the potential for interference competition amongst G. caesaris and adults and juveniles of G. simonyi. Movement patterns and activity levels of individuals were quantified. No interspecific aggressive interactions were observed, however, distance moved and activity of G. simonyi changed as a result of the addition of conspecifics and of individuals of the smaller,more active, species. These results suggest that the presence of G. caesaris has the potential to influence behavior and energetics of G. simonyi. Interestingly, a similar species association exists on the nearby island of Gran Canaria, in which a large and numerous lizard G. stehlini is geographically sympatric with a smaller species, G. atlantica. Interspecific aggressive interactions (including predation!) were observed in G. stehlini towards G. atlantica, and distance moved and activity of G. stehlini did not change in presence of G. atlantica.
Cooper Jr., W.E. & Caldwell, J.P. & Vitt, L.J. & Pérez-Mellado, V. & Baird, T.A. (2002) -
Lizards use chemical cues to locate and identify prey and plant food, assess the nutritional quality of food, and detect plant toxins. Among insectivorous lizards, all actively foraging species studied respond strongly to prey chemicals sampled lingually, but ambush foragers do not. Much recent research has been devoted to assessing differential responses to food and nonfood chemicals (i.e., food-chemical discrimination) by omnivorous and herbivorous species and determining whether correlated evolution has occurred between plant diet and plant-chemical discrimination. We conducted experimental studies of food-chemical discrimination by two species of teiid lizards, the omnivorous Cnemidophorus murinus and the actively foraging insectivorous Ameiva ameiva. The omnivore distinguished both prey and plant chemicals from control substances. The insectivore exhibited prey-chemical, but not plant-chemical, discrimination, as indicated by tongue-flicking and biting. A comparative analysis using concentrated-changes tests showed that correlated evolution has occurred between plant consumption and plant-chemical discrimination in a major lizard taxon, Lacertiformes. These results extend and strengthen previous findings of similar correlated evolution to a new group and add to a growing database indicating that omnivorous lizards use chemical cues to assess both prey and plant foods.
Cooper Jr., W.E. & Pérez-Mellado, V. (2001) -
Many lizards can identify food using only chemical cues, as indicated by tongue-flicking for chemical sampling and biting, but the effectiveness of the chemical components of food are unknown, as is the relationship between response strength and concentration. We investigated responses by the omnivorous lizard Gallotia caesaris to representatives of two major categories of organic food chemicals, lipids and carbohydrates. The stimuli, pork fat and sucrose solutions of varying concentration, were presented to lizards on cotton swabs and their lingual and biting behaviors were observed during 60-s tests. In the first experiment, fat elicited more tongue-flicks and bites than saturated sucrose or water (odorless control), biting being limited to the fat condition. Lizards licked at high rates, but exclusively in response to sucrose. A lick was a lingual protrusion in which the dorsal surface of the tongue contacted the swab, in contrast to the anteroventral contact made during tongue-flicks. In a second experiment, the number of licks, but not the number of tongue-flicks, increased with the concentration of sucrose. The results indicate that lipids contribute to prey chemical discrimination and are adequate to release some attacks, but are not as effective as releasers of attack as mixtures of prey chemicals obtained from prey surfaces. The findings with respect to licking are novel, and suggest that licking may be a response to gustatory stimulation by sugar, in contrast to previously observed prey chemical discriminations shown to require vomerolfaction.
We studied lingual and biting responses to food chemicals by two species of omnivorous lacertid lizards, the Canary Island endemics Gallotia simonyi (the giant lizard of El Hierro) and Gallotia caesaris (Boettger`s lizard), to ascertain their ability to discriminate between prey and plant food chemicals on the one hand and control stimuli on the other. We recorded frequencies of tongue-flicking and latency to bite in 60-s trials in which chemical stimuli on cotton-tipped applicators were presented to the lizards. Both species exhibited prey-chemical discrimination, as indicated by elevated tongue-flick rates and higher proportions of individuals biting in response to surface chemicals from crickets. Both species exhibited plant-chemical discrimination, as indicated by significantly greater tongue-flick rates and biting frequency in response to chemicals from tomato fruit than to the control stimuli. Juvenile G. simonyi responded much more strongly to chemical stimuli from tomato fruit than from leaves of Psoralea bituminosa, which is not a preferred food for juveniles. The findings are consistent with the hypothesis that chemosensory discrimination evolves in omnivorous lizards to permit evaluation of food quality, resulting in correspondence between plant diet and plant-chemical discrimination, both being absent in insectivores. The results are also consistent with the hypothesis that prey-chemical discrimination is retained and plant-chemical discrimination evolves in the omnivorous lizards derived from actively foraging insectivores.
Cox, S.C. & Carranza, S. & Brown, R.P. (2010) -
The Canary Islands have become a model region for evolutionary studies. We obtained 1.8 Kbp of mtDNA sequence from all known island forms of the endemic lizard genus Gallotia and from its sister taxon Psammodromus in order to reanalyze phylogenetic relationships within the archipelago, estimate lineage divergence times, and reconstruct the colonization history of this group. Well-supported phylogenies were obtained using maximum parsimony and Bayesian inference. Previous studies have been unable to establish the branching pattern at the base of the tree. We found evidence that G. stehlini (Gran Canaria) originated from the most basal Gallotia node and G. atlantica from the subsequent node. Divergence times were estimated under a global clock using Bayesian Markov Chain Monte Carlo methods implemented by three different programs: BEAST, MCMCTREE, MULTIDIVTIME. Node constraints were derived from subaerial island appearance data and were incorporated into the analyses as soft or hard maximal bounds. Posterior node ages differed slightly between programs, possibly due to different priors on divergence times. The most eastern Canary Islands first emerged just over 20 mya and their colonization appears to have taken place relatively quickly, around 17–20 mya. The subsequent node is consistent with cladogenesis due to colonization of Gran Canaria from the eastern islands about 11–13 mya. The western islands appear to have been colonized by a dispersal event from Lanzarote/Fuerteventura in the east to either La Gomera or one of the ancient edifices that subsequently formed Tenerife in the west, about 9–10 mya. Within the western islands, the most recent node that is ancestral to both the G. intermedia/G. gomerana/G. simonyi and the G. galloti/G. caesaris clades is dated at about 5–6 mya. Subsequent dispersal events between ancient Tenerife islands and La Gomera are dated at around 3 mya in both clades, although the direction of dispersal cannot be determined. Finally, we show that G. galloti is likely to have colonized La Palma more than 0.5 Ma after emergence of the island 1.77 mya, while G. caesaris from the same clade may have colonized El Hierro very soon after it emerged 1.12 mya. There are tentative indications that the large-bodied endangered G. simonyi colonized El Hierro around the same time or even later than the smaller-bodied G. caesaris. This study demonstrates the effectiveness of Bayesian dating of a phylogeny in helping reconstruct the historical pattern of dispersal across an oceanic archipelago.
Delgado Castro, G. (2007) -
Evenhuis, T. (2006) -
Herpetological observations on La Gomera in November 2005 The author visited La Gomera (the Canaries) in November 2005. This is the second smallest island of the archipelago, which consists of islands that arose from volcanic actions. The age and the isolated location gave rise to several endemic species. The species occurring most often on La Gomera is Gallotia caesaris (males up to 30 cm), which was found in several biotopes. This animal is found on El Hierro too. Gallotia gomerana is a large lizard (50-60 cm), that until recently was thought of as being extinct. After its rediscovery in 1999 the animals are kept and bred in a breeding-centre on the island. It is an endemic species. Chalcides viridanus is a skink that was observed in several habitats too. This species can be found on other islands (El Hierro and Tenerife). Tarentola gomerensis is a widespread gecko, found in many biotopes. This species is found only on La Gomera. Hyla meridionalis is a more recent immigrant, which arrived on the archipelago from southern Europe, probably by human interference. The only possible other species that could perhaps be found on the island is Rana perezi This animal was not observed.
Foronda, P. & Santana Morales, M. & Oros, J. & Abreu-Costa, N. & Ortega Arivas, A. & Lorenzo Morales, J. & Valladares, B. (2007) -
Intestinal helminths and blood protozoa are common parasites of lizards. In captivity they can be a serious problem, but no information on treatments is available. In this study, several antiparasitic drugs were studied in Gallotia caesaris (Lacertida) from La Gomera, the Canary Islands, Spain. A lack of efficacy of chloroquine, and a decrease in haemogregarine (Apicomplexa) infection by atovaquone-proguanil was demonstrated. Furthermore, a positive effect of fenbendazole against intestinal nematode infection was observed. In the Canary Islands, Gallotia bravoana and Gallotia simonyi (Lacertida) are included in a captive breading recovery plan. The present results are useful in order to keep these animals in good condition and to control their parasites. Moreover, these results are important for reptiles kept as pets, due to the previous lack of knowledge of parasite management.
Friedli, S. & Ackermann, G. (2022) -
Garcia Marquez, M. & Mateo-Miras, J.A. & Lopez Jurado, L.F. (1998) -
Garcia-Márquez, M. & López-Jurado, L.F. & Mateo, J.A. (1999) -
In islands, small sized lizard species are less vulnerbale to mammalian predators introduced by man than big sized species. Since this might be relatied to how the life history traits of the lizards covariate with body size, eco-demographic studies on the small, extinction resistant insular species have value for conservation science. In the small G. caesaris from El Hierro island, early maturity (which involves big hatchling size but small adult size) and multiple broods per season compensate for high mortality rates in a population subjected to kestrel and introduced feral cat predation. A severe drought increased slightly the mortality of the adults, but the population density dropped by a factor of three as the result of a reduction in the reproductive performance of the lizards. Bigger size meant enhanced fitness and fecundity but, since size is limited by asymptotic growth, size is poorly correlated with age, and life expectancy is short, natural selection should favour the younger breeders in this species.
Garcia-Porta, J. & Irisarri, I. & Kirchner, M. & Rodríguez, A. & Kirchhof, S. & Brown, J.L. & MacLeod, A. & Turner, A.P. & Ahmadzadeh, F. & Albaladejo, G. & Crnobrnja-Isailovic, J. & Riva, I. de la & Fawzi, A. & Galán, P. & Göçmen, B. & Harris, D.J. & Jiménez-Robles, O. & Joger, U. & Jovanović Glavaš, O. & Karış, M. & Koziel, G. & Künzel, S. & Lyra, M. & Miles, D. & Nogales, M. & Oğuz, M.A. & Paf (2019) -
Climatic conditions changing over time and space shape the evolution of organisms at multiple levels, including temperate lizards in the family Lacertidae. Here we reconstruct a dated phylogenetic tree of 262 lacertid species based on a supermatrix relying on novel phylogenomic datasets and fossil calibrations. Diversification of lacertids was accompanied by an increasing disparity among occupied bioclimatic niches, especially in the last 10 Ma, during a period of progressive global cooling. Temperate species also underwent a genome- wide slowdown in molecular substitution rates compared to tropical and desert-adapted lacertids. Evaporative water loss and preferred temperature are correlated with bioclimatic parameters, indicating physiological adaptations to climate. Tropical, but also some popu- lations of cool-adapted species experience maximum temperatures close to their preferred temperatures. We hypothesize these species-specific physiological preferences may con- stitute a handicap to prevail under rapid global warming, and contribute to explaining local lizard extinctions in cool and humid climates.
Glandt, D. (2010) -
Gonzáles, P. & Pinto, F. & Nogales, M. & Jiménez-Asensio, J. & Hernández, M. & Cabrera, V.M. (1996) -
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.
Großhans, R. (2017) -
Helmdag, A. (1991) -
Izquierdo, I. & Medina, A.L. & Hernández, J.J. (1989) -
A new deposit of giant lacertids is described from a volcanic cave in the western part of El Hierro island. On the basis of an analysis of the 388 pieces found in this deposit, using both the literature and osteological material from Tenerife and El Hierro, it is concluded that three different species are represented: Gallotia goliath (Mertens), now extinct in the Canary Islands, Gallotia simonyi (Stein.) and Gallotia galloti caesaris (Lehrs). The two last species are still present on the island. The presence of G. goliath in this deposit represents the first record of this species in the island of El Hierro.
Jorge, F. & Perera, A. & Carretero, M.A. (2013) -
The implementation of molecular tools in parasitology has led to the discovery of numerous cryptic species. However, detailed morphological studies are needed to evaluate the cryptic nature of such species, as well as to provide an appropriate and formal description. Recent phylogenetic analyses using mitochondrial and nuclear genes have revealed that the nematode Spauligodon atlanticus, parasite of lizards of the genus Gallotia endemic to the Canary Islands, consists of two highly divergent and unrelated lineages, one in the eastern islands and the other in the western ones. This study provides a detailed morphological analysis of the two S. atlanticus lineages characterized genetically, based on body measurements and scanning electron microscopy. This integrative approach revealed phenotypic differences between them, despite their overall morphological resemblance. As a result, the new species Spauligodon occidentalis sp. nov., from the formerly western lineage, is described. The morphological similarity between the two Spauligodon species is better explained on the basis of evolutionary convergence, since both species parasitize Gallotia lizards. In addition to delimiting the new nematode species, this study highlights the importance of combining genetic and morphological data with taxonomy to uncover the nature of cryptic species and decrease taxonomic uncertainty.
Lehrs, P. (1914) -
Lindner, L. (2010) -
Lindner, L. (2016) -
Lopez-Darias, M. & Vanhooydonck, B. & Cornette, R. & Herrel, A. (2015) -
1. Males and females often differ from one another in phenotypic traits due to differential investment in traits relevant to the fitness of each sex. However, how differences in sexually dimorphic traits affect ecologically relevant performance traits and whether these are correlated with variation in ecology remains poorly understood. 2. Here, we test the co-evolution of head shape, bite force capacity and diet in male and female lizards (Gallotia) from the Canary Islands, known to be sexually dimorphic. We collected data on bite force and head size and shape for both sexes of all seven extant species on all seven islands of the archipelago (ten evolutionary-independent lineages). Moreover, we collected diet data for five out of the seven species (eight lineages). 3. Our results show that the evolution of head morphology is associated with the evolution of bite force in both sexes. However, only in females is the evolution of head morphology and bite force associated with the evolution of diet. In males, head morphology and bite force are decoupled from the evolution of diet. In conjunction with the male head shape characterized by a broad rostrum, this suggests that head shape and bite force may be evolving principally under sexual selection in males. 4. Our data thus suggest that head morphology and associated functional traits may evolve under different selective pressures in the two sexes.
López-Jurado, L.F. & Mateo, J.A. (1997) -
Machado, A. & L. F. López-Jurado, A. Martín (1985) -
Mamin, A. & C. Rodriguez (2021) -
Gallotia is an endemic genus of Lacertidae from the Canary Islands. This genus is known to be omnivorous. It displays an opportunistic feeding behaviour and feeds on a wide variety of food with an important part made of plant matters, including stems, leaves, flowers and fruits. Its diet includes arthropods, other lizards, various animal carrions and even human leftover food too. Two species among the genus Gallotia have been reported to practice coprophagy. Here, the authors share personal observations of this behaviour in three other species of the same genus.
Márquez, R. & Cejudo, D. (2000) -
We studied the occurrence of threat display as a defensive behavior at different temperatures in two large-sized (Gallotia simonyi and Gallotia stehlini) and two small-sized (Gallotia atlantica and Gallotia caesaris) lacertids from the Canary Islands. Lizards were chased on a linear track at five temperatures (24, 28, 32, 36, and 40 C). Only adult individuals of the two large-sized species sporadically adopted the threat display, and G. stehlini used the display more often than did G. simonyi. Among these, there was no clear pattern of relationship between temperature and probability of display nor differences between sexes.
Martin, J.E. & Llorente, G.A. & Roca, V. & Carretero, M.A. & Montori, A. & Santos, X. & Romeu, R. (2005) -
Diet and helminth fauna were analysed in Gallotia caesaris, a small lacertid lizard endemic to El Hierro (Canary Islands, Spain) in order to study the evolutionary and functional relationships between the two traits. This species is omnivorous but consumed a high proportion (82.13%) of plant matter including not only seeds but also leaves and other vegetative parts. Helminth fauna included many helminth species typical of herbivorous reptiles. Both herbivory and helminth presence were higher than expected for a lizard of its size. Comparison with other lacertids suggests that both traits result from an adaptation to insular conditions but that some “evolutionary time” to develop them is needed. Canarian Gallotia lizards, a separate lineage evolving for a long time in insularity, constitutes the most advanced lacertid group in this way. Nevertheless, results for G. caesaris indicate that helminth fauna also changes seasonally tracking variation in diet (and herbivory) throughout the year, which suggests a dynamic interaction between diet and helminth parasites.
Martin, J.E. & Roca, V. (2004) -
A survey of gastrointestinal helminth communities of Gallotia caesaris caesaris (Lehrs, 1914) and G. c. gomerae (Boettger and Müller, 1914), from the islands of El Hierro and La Gomera, respectively, in the Canary Archipelago, Spain, was conducted to determine the prevalence, intensity, and diversity of intestinal parasites of these lacertid lizards. Larval forms of cestodes, nematodes, and acanthocephalans were found in the body cavity of G. c. caesaris; this lizard is the intermediate or paratenic host in the life cycle of these helminths. Pharyngodonid nematodes were the most common intestinal helminths in both hosts, 4 of them being Gallotia spp. specialists. Helminth infracommunities of both hosts were depauperate and isolationist, according to the low values of helminth diversity.
Masó, A. & Pijoan, M. (2011) -
Mateo, J.A. & Garcia-Márquez, M. (2002) -
Mayer, W. & Bischoff, W. (2001) -
Meiri, S. (2008) -
Aim Body size is instrumental in influencing animal physiology, morphology, ecology and evolution, as well as extinction risk. I examine several hypotheses regarding the influence of body size on lizard evolution and extinction risk, assessing whether body size influences, or is influenced by, species richness, herbivory, island dwelling and extinction risk. Location World-wide. Methods I used literature data and measurements of museum and live specimens to estimate lizard body size distributions. Results I obtained body size data for 99% of the world`s lizard species. The body size–frequency distribution is highly modal and right skewed and similar distributions characterize most lizard families and lizard assemblages across biogeographical realms. There is a strong negative correlation between mean body size within families and species richness. Herbivorous lizards are larger than omnivorous and carnivorous ones, and aquatic lizards are larger than non-aquatic species. Diurnal activity is associated with small body size. Insular lizards tend towards both extremes of the size spectrum. Extinction risk increases with body size of species for which risk has been assessed. Main conclusions Small size seems to promote fast diversification of disparate body plans. The absence of mammalian predators allows insular lizards to attain larger body sizes by means of release from predation and allows them to evolve into the top predator niche. Island living also promotes a high frequency of herbivory, which is also associated with large size. Aquatic and nocturnal lizards probably evolve large size because of thermal constraints. The association between large size and high extinction risk, however, probably reflects a bias in the species in which risk has been studied.
Meiri, S. & Bauer, A.M. & Chirio, L. & Colli, G.R. & Das, I. & Doan, T.M. & Feldman, A. & Herrera, F.-C. & Novosolov, M. & Pafilis, P. Pincheira-Donoso, D. & Powney, G. & Torres-Carvajal, O. & Uetz, P. & Van Damme, R. (2013) -
Aim Temperature influences most components of animal ecology and life history – but what kind of temperature? Physiologists usually examine the influence of body temperatures, while biogeographers and macroecologists tend to focus on environmental temperatures. We aim to examine the relationship between these two measures, to determine the factors that affect lizard body temperatures and to test the effect of both temperature measures on lizard life history. Location World-wide. Methods We used a large (861 species) global dataset of lizard body temperatures, and the mean annual temperatures across their geographic ranges to examine the relationships between body and mean annual temperatures.We then examined factors influencing body temperatures, and tested for the influence of both on ecological and life-history traits while accounting for the influence of shared ancestry. Results Body temperatures and mean annual temperatures are uncorrelated. However, accounting for activity time (nocturnal species have low body temperatures), use of space (fossorial and semi-aquatic species are ‘colder’), insularity (mainland species are ‘hotter’) and phylogeny, the two temperatures are positively correlated. High body temperatures are only associated with larger hatchlings and increased rates of biomass production. Annual temperatures are positively correlated with clutch frequency and annual longevity, and negatively correlated with clutch size, age at first reproduction and longevity. Main conclusions Lizards with low body temperatures do not seem to have ‘slower’ life-history attributes than species with high body temperatures. The longer seasons prevalent in warm regions, and physiological processes that operate while lizards are inactive (but warm enough), make environmental temperatures better predictors of lizard life-history variation than body temperatures. This surprisingly greater effect of environmental temperatures on lizard life histories hints that global warming may have a profound influence on lizard ecology and evolution.
Mertens, R. & Müller, L. (1940) -
Molina Borja, M. (1986) -
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.
Molina Borja, M. & Rodriguez-Dominguez, M.A. (2004) -
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.
Molina-Borja, M. (1980) -
Molina-Borja, M. & Rodriguez-Dominguez, M.A. & Gonbzález-Ortega, C. & Bohórquez-Alonso, M.L. (2010) -
We co mpared sexual dimorphism of body and head traits from adult lizards of populations of Gallotia caesaris living in ecologically different habitats of El Hierro and La Gomera. Males had larger body sizes than females, and sexual size and shape dimorphism were greater in a population from La Gomera than in three populations from El Hierro. Multivariate analysis of variance, using linear and shape-adjusted traits, showed that the populations differed significantly in body and head traiuts, with pileus (head) width, snout-vent length (SVL), and body mass the main traits contributing to the differences. Males had larger SVL, heads, and limbs than females in all populations, but SVL relative to a shape index (calculated as the geometric mean of several body parameters) was larger in females than in males. Moreover, shapeadjusted hind-lim b lengths were significantly shorter in lizards from the more densely vegetated habitats than in those from the less vegetated ones. The magnitude of msexual dimorphism was largere for relative limb length and head depth in the population with less vegetation than in those with more vegetation. Our data suggest that morphological differences between populations reflect local adaptations to habitat structure.
Montori, A. & Llorente, G.A. (2005) -
Nogales, M. & Hernandez, E. & Delgado, G. & Quintero, A. (1990) -
The floristic and faunistic communities of Roque Grande de Salmor off the North coast of El Hierro is described. In the highest part of the islet, a small previously unrecorded population of Gallotia galloti caesaris has been found .
Pérez i de Lanuza, G. & Font, E. (2016) -
Many animals display complex colour patterns that comprise several adjacent, often contrasting colour patches. Combining patches of complementary colours increases the overall conspicuousness of the complex pattern, enhancing signal detection. Therefore, selection for conspicuousness may act not only on the design of single colour patches, but also on their combination. Contrasting long- and short-wavelength colour patches are located on the ventral and lateral surfaces of many lacertid lizards. As the combination of long- and short-wavelength-based colours generates local chromatic contrast, we hypothesized that selection may favour the co-occurrence of lateral and ventral contrasting patches, resulting in complex colour patterns that maximize the overall conspicuousness of the signal. To test this hypothesis we performed a comparative phylogenetic study using a categorical colour classification based on spectral data and descriptive information on lacertid coloration collected from the literature. Our results demonstrate that conspicuous ventral (long wavelength-based) and lateral (short wavelength-based) colour patches co-occur throughout the lacertid phylogeny more often than expected by chance, especially in the subfamily Lacertini. These results suggest that selection promotes the evolution of the complex pattern rather than the acquisition of a single conspicuous colour patch, possibly due to the increased conspicuousness caused by the combination of colours with contrasting spectral properties.
Pérez-Mellado, V. & Traveset, A. (1999) -
Different kinds of interactions between lizards and plants in the Mediterranean basin have been described. Lizards have shown to `use` plants as a refuge against predators, as a foraging site, as a thermal microhabitat or as a food resource. In the last case, they can either act as herbivores (+/- interaction, consuming vegetative and/or reproductive parts, and damaging the plant to a higher or lower degree) or as mutualists (+/+ interaction, by behaving as legitimate pollinators and/or seed dispersers). The importance of plants as a food resource for Mediterranean lizards has been found to be high in insular habitats, espescially in small islands, where the paucity of arthropod prey availability redirects the foraging activity of lizards towards other nutrient resources. In such small islands, plants may play a major role in the trophic ecology of lacertid lizards, as suggested by recent studies. Likewise, lizards may be important both as efficient pollen transporters and seed dispersersfor a variety of plants. Some of these lizard-plant interactions are unique. The effect lizards have on the reproductive and dispersal succes of some species may be very relevant for plant preserveation, and in turn, the preserveation of prticular behavioral and ecological traits of the particular lizard populations depends, at least partly, on the plants they interact with.
Pinho, R. & Izquierdo, E. & Rodriguez, J.L. & Foronda, P. (2021) -
Rivera, X. & Arribas, O. & Martí, F. (2001) -
Rodriguez Dominguez, M.A. (2000) -
Salvador, A. (2009) -
Salvador, A. & Pleguezuelos, J.M. & Reques, R. (2021) -
Schäberle, C. & Schäberle, A. (2019) -
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!
Siliceo, I. & Díaz, J.A. (2010) -
Whereas the range size of endangered species is undoubtfuly useful to predict risk of extinction, the role of their life-history characteristics is much less clear, and their effects may depend on the nature of the threatening factors. Such factors, for instance, are known to be different on islands and on the mainland. We used phylogenetically based statistical analyses to study the relationships among conservation status, insularity, range size, and life-history traits in a clade of Western Palaearctic lacertids including insular and continental species. These lizards are ecologically similar, but they show wide variation in life-history traits and vulnerability to extinction. Insular species of a given size had smaller clutches than mainland ones. Degree of threat was best predicted by a logistic regression including range size, insularity, clutch size, and the insularity × clutch size interaction. On the mainland, but not on islands, threatened species had smaller clutches than non-threatened ones. On islands, small clutch size is probably an adaptive trait, and it might predispose certain species to extinction, but the intrinsic characteristics of such species remain unclear. However, small clutch size was a good predictor of extinction risk on the mainland, having evolved most frequently in late maturing species from montane habitats in which climatic conditions limit their reproductive output and increase their vulnerability to stochastic hazards or habitat fragmentation.
Sivereo, F. & Rodriguez-Rodriguez (2011) -
Siverio, F. & Rodríguez-Rodríguez, M.C. (2011) -
Speer, E. O. (1994) -
On EI Hierro, Canary Isiands, the endemic Iizard Gallotia galloti caesaris was observed visiting the flowers of the likewise endemic Euphorbia broussonetii in search of nectar. For such piants visited and quite likely pollinated by Iizards, the collective term Saurophilae is proposed. Poiyphilous and monophilous biossoms are distinguished .
Speybroeck, J. & Beukema, W. & Dufresnes, C. & Fritz, U. & Jablonski, D. & Lymberakis, P. & Martinez-Solano, I. & Razzettis, E. & Vamberger, M. & Vences, M. & Vörös, J. & Crochet, P.-A. (2020) -
The last species list of the European herpetofauna was published by Speybroeck, Beukema and Crochet (2010). In the meantime, ongoing research led to numerous taxonomic changes, including the discovery of new species-level lineages as well as reclassifications at genus level, requiring significant changes to this list. As of 2019, a new Taxonomic Committee was established as an official entity within the European Herpetological Society, Societas Europaea Herpetologica (SEH). Twelve members from nine European countries reviewed, discussed and voted on recent taxonomic research on a case-by-case basis. Accepted changes led to critical compilation of a new species list, which is hereby presented and discussed. According to our list, 301 species (95 amphibians, 15 chelonians, including six species of sea turtles, and 191 squamates) occur within our expanded geographical definition of Europe. The list includes 14 non-native species (three amphibians, one chelonian, and ten squamates).
Troidl, A. & Troidl, S. (2004) -
Während unseres Aufenthaltes auf der Insel La Gomera konnten wir die Kleine Kanareneidechse (Gallotia caesaris gomerae), den Kanarenskink (Chalcides viridanus coeruleopunctatus) und den Gomera-Gecko (Tarentola gomerensis) meist im selben Lebensraum antreffen. Gelegentlich trafen wir diese sehr unterschiedlichen Reptilien gemeinsam beim Sonnenbaden an, wobei der Abstand der Tiere zueinander oftmals nur wenige Zentimeter betrug. Besonders zahlreich kommen diese Reptilien in Gegenden mit landwirtschaftlicher Nutzung vor. Bei einem Ausflug ins Valle Gran Rey besuchten wir auch die neu errichtete Zuchtstation der Gomera-Rieseneidechsen (Gallotia simonyi bravoana). Im Bereich der an der Nordostküste gelegenen Ortschaft Agulo fanden wir neben den zahlreichen Eidechsen auch außergewöhnlich viele Geckos und Skinke.
Troidl, S. & Troidl, A. (2016) -
From 20.4.-26.4.2015 as well as from 14.4.-26.4.2016 we visited the Canary Island of El Hierro. Our particular interest was directed towards the El Hierro giant lizard (Gallotia simonyi) and Boettger’s lizard (Gallotia caesaris caesaris). With our pictures of the Mediterranean Tree Frog (Hyla meridionalis) from the plateau near Tiñor, we are finally able to give proof of its existence on El Hierro.