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of the real lizards, family Lacertidae
Gallotia galloti galloti (OUDART, 1839)
Amat, J.A. & Martinez-de-la-Torre, M. & Trujillo, C.M. & Fernández, B. & Puelles, L. (2022) -
In the developing brain, the phenomenon of neurogenesis is manifested heterotopically, that is, much the same neurogenetic steps occur at different places with a different timetable. This is due apparently to early molecular regionalization of the neural tube wall in the anteroposterior and dorsoventral dimensions, in a checkerboard pattern of more or less deformed quadrangular histogenetic areas. Their respective fate is apparently specified by a locally specific combination of active/repressed genes known as “molecular profile.” This leads to position-dependent differential control of proliferation, neurogenesis, differentiation, and other aspects, eventually in a heterochronic manner across adjacent areal units with sufficiently different molecular profiles. It is not known how fixed these heterochronic patterns are. We reexamined here comparatively early patterns of forebrain and hindbrain neurogenesis in a lizard (Lacerta gallotia galloti), a bird (the chick), and a mammal (the rat), as demonstrated by activation of acetylcholinesterase (AChE). This is an early marker of postmitotic neurons, which leaves unlabeled the neuroepithelial ventricular cells, so that we can examine cleared wholemounts of the reacted brains to have a birds-eye view of the emergent neuronal pattern at each stage. There is overall heterochrony between the basal and alar plates of the brain, a known fact, but, remarkably, heterochrony occurs even within the precocious basal plate among its final anteroposterior neuromeric subdivisions and their internal microzonal subdivisions. Some neuromeric units or microzones are precocious, while others follow suit without any specific spatial order or gradient; other similar neuromeric units remain retarded in the midst of quite advanced neighbors, though they do produce similar neurogenetic patterns at later stages. It was found that some details of such neuromeric heterochrony are species-specific, possibly related to differential morphogenetic properties. Given the molecular causal underpinning of the updated prosomeric model used here for interpretation, we comment on the close correlation between some genetic patterns and the observed AChE differentiation patterns.
Arechavaleta, M. & S. Rodríguez & N. Zurita & A. García (coord.) (2010) -
Báez, M. (1984) -
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.
Bille, T. (1997) -
Bischoff, W. (1971) -
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. (2015) -
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.
Bohórquez-Alonso, M. & Font, E. & Molina-Borja, M. (2011) -
In lizards, site selection is related to the acquisition of resources such as refuges, mates or prey, but also to the exploitation of sites suitable for thermoregulation. The latter process may be affected by lizard posture and body axis orientation in relation to the sun as a way to optimize heat exchange throughout the day. Specific postures and body orientations could also contribute to more efficient signal transmission in social contexts. In this paper we analyze activity and body axis orientation of adult males and females of the lacertid Gallotia galloti in two localities of Tenerife with different structural habitats. We performed transects at both sampling localities in the morning and at midday during May and June of three years (2002-2004). The numbers of lizards detected per unit time during transects at both localities were similar; however, significantly more males than females were detected. Moreover, more lizards were found oriented parallel or perpendicular to the sun than in alternative (oblique) orientations. Heating rates were not different for copper lizard models oriented parallel or perpendicular to the sun, neither in the morning nor at midday, and there was no significant relationship between air temperature and lizard body orientation. This suggests that lizard body orientation is not constrained by thermoregulatory requirements. We discuss alternative hypotheses and conclude that body axis orientation in G. galloti lizards may reflect a compromise between the conflicting demands imposed by thermoregulation and social communication.
Bowler, J. (2018) -
Delgado Castro, G. (2007) -
Duméril, A.M.C. & Bibron, G. (1839) -
Filson, R.P. (2004) -
Font, E. & Molina-Borja, M. (2001) -
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.
Helmdag, A. (1991) -
Howard, C.J. (1980) -
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.
Krefft, G. (1949) -
Machado, A. & L. F. López-Jurado, A. Martín (1985) -
Mayer, W. & Bischoff, W. (1991) -
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.
Méndez-Álvarez, A. (2024) -
Mertens, R. (1970) -
Molina Borja, M. (1981) -
Molina Borja, M. & Padron-Fumero, M. & Alfonso-Martin, T. (1998) -
This study describes the sequence of behaviour during aggressive encounters between male ‘tizón’ lizards (G. galloti galloti) and assesses the effect of morphological and behavioural traits on the outcome and intensity of staged aggressive encounters between males. Aggressive encounters ranged from only throat extension to escalated fights with biting and rolling over. Winners were heavier, had longer heads, and performed tongue-flicking, throat extension and biting at a higher rate than losers. The rate of aggressive behaviour increased with decreasing difference in snout-to-vent length, head length and head width of the contestants. The results are in agreement with some predictions of the sequential assessment game model in that probability of victory increased with the difference in fighting ability and that the rate of aggressive behaviour was higher in contests between animals of similar size.
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. & Font, E. & Mesa Ávila, G. (2006) -
Sex and population differences in the ultraviolet (UV) reflectance patterns of two phenotypically divergent lacertids from Tenerife, Gallotia galloti eisentrauti and G. g. galloti, are described. Adults in both populations have rows of lateral and ventro-lateral blue patches on either side of the trunk that show a single peak of reflectance in the near UV. The lateral patches of males are more intensely reflective than those of females, but females have more chromatic and UV-shifted lateral patches than males. Most G. g. eisentrauti and some G. g. galloti also have blue cheek patches on either side of the gular area. Male cheek patches have reflectance peaks in the near UV, whereas those of females peak in the visible part of the spectrum. The lateral patches of males from the two populations differ in hue but not in intensity, those of G. g. galloti being more UV-shifted than those of G. g. eisentrauti. Female G. g. galloti have more intensely reflective lateral patches than female G. g. eisentrauti. Interindividual variation in peak wavelength and/or UV chroma is present in both sexes and populations. This is the first demonstration of sexual dichromatism in the UV reflectance of colour patches in a lacertid.
Roca, V. & Carretero, M.A. & Llorente, G.A. & Montori, A. & Martin, J.E. (2005) -
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.
Rodriguez-Dominguez, M.A. & Santos, A. de los & Cantarella, F. (1994) -
Sacha, M. (2017) -
Santos, A. De Los & Nicolás, J.P. De (2008) -
Relationships among environmental patterns and population size of the smut lizard Gallotia galloti galloti Oudart, 1839 (Sauria Lacertidae) were examined in the context of longer time-scale variability on a sandy beach and adjacent environments of Southeastern Tenerife. Seasonal and yearly patterns in the population size were likewise analyzed in relation to climatic and anthropic variables. Six sampling plots (coastal, sweet tabaiba, tuff, lava, sandy lava and crater) were selected following a perpendicular transect to the sandy fringe that extends from the beach toward the volcanic interior. Pitfall trapping was conducted from 1984 to 2005, and capture–mark–recapture technique and the Jolly–Seber method were used to estimate population sizes. The highest population size estimates were shown on the sandy lava plot and the neighboring lava plot, reaching values of about 3500 individuals ha−1 during the spring. The population was active almost the whole year, with seasonal patterns of activity from March to October. Seasonal temperature and population size patterns were correlated but the ‘calima’ episodes produced some disturbance. Gallotia galloti galloti was one of the most abundant lizards of all the species studied and its population size has not remained stable over the study period, probably because of the absence of predation and competition, and because of human interference and environmental instability.
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!
Bizarre Felsstrukturen, exotische Pflanzen und gierige Eidechsen lassen sich in einem Wort zusammenfassen: Teneriffa. Die größte Insel der Kanaren ist geprägt vom Pico del Teide, Spaniensn höchsten Berg mit 3.718 m ü. NN. Dadurch bietet sie die verschiedensten Klimazonen auf engstem Raum – und eine Heimat für Kanareneidechsen mehrerer Taxa.
Thorpe, R.S. (1985) -
Troidl, A. & Troidl, S. (2002) -
Troidl, S. & Troidl, A. (2014) -
areas in different landscapes and climatic zones. Our special interest was the herpetofauna of this island that is poor in species numbers but nonetheless very interesting. One focus was the search for the Tenerife Speckled Lizard (Gallotia intermedia) in the South and Southwest of the island.
Zawadzki, M. (2018) -
Zimmermann, H. (1984) -