Data on population parameters obtained by the capture-mark-recapture method using a grid with 121... more Data on population parameters obtained by the capture-mark-recapture method using a grid with 121 trapping stations during 13 continuos months, were related to relative indexes of food availability, consumption and preference through Principal Component Analyses. Marmosas population density tends to have a strong and positive correlation to a diet of animal origen when individuals are mainly no-reproductive. Presence of lactating females, as well as the minimal survival rate, also tend to be positively correlated with biomass peaks of Coleoptera, larvae, and ripe fruits of Cactacea species. On the other hand, home range size and arboreal activity showed had no significant correlations to the environmental variables. Marmosas movements are determined by its familiarity of surroundings rather than food availability. To reach conclusive results, further studies must concider quantification of availability, consumption and preference indexes, as well as extention of total time the varia...
... The dominant thorn forest vegetation near the cave includes : columnar cacti (Ste-nocereus gr... more ... The dominant thorn forest vegetation near the cave includes : columnar cacti (Ste-nocereus griseus, Cereus (Subpilocereus) repandus), mesquite (Prosopis juliflora), leguminous trees such as Erythrina velutina and Cercidium praecox, prickly pear (Opuntia (wentiana ...
The moustached bats, Pteronotus davyi, P. personatus, and P. parnellii, and the ghost-faced bat, ... more The moustached bats, Pteronotus davyi, P. personatus, and P. parnellii, and the ghost-faced bat, Mormoops megalophylla (Mormoopidae), are homeotherms with normal to slightly low basal rates of metabolism for mammals of their body mass. They are unable to resist ...
Marmosa is the most species-rich genus of living marsupials, and its members are distributed near... more Marmosa is the most species-rich genus of living marsupials, and its members are distributed nearly all over the available habitats in the Neotropics. M. robinsoni and M. xerophila are two species belonging to this genus. M. robinsoni is spread throughout the Llanos and the rainforest; while M. xerophila is found in semi-arid ecosystems. A very close phylogenetic relationship between these two species has been claimed. In the present paper, our main goal is to measure some population parameters of M. xerophila and study the effects on them caused by the seasonal variability of a semi-arid ecosystem, not only to learn about the species’ natural history but also to estimate the significance of these adaptations, when comparing them to the information already known about M. robinsoni in other ecosystems. The results show that the different parameters which govern the population dynamics of M. xerophila are synchronized with environment variations. This synchronization or seasonality is...
... Abraham Mijares-Urrutia, Alexis Arends R. ... En Venezuela, las lagartijas del género Gonatod... more ... Abraham Mijares-Urrutia, Alexis Arends R. ... En Venezuela, las lagartijas del género Gonatodes Fitzinger, popularmente llamados "Tuqueques" (Rivero-Blanco, 1967), son las mAs divers as entre los gecónidos, habién-dose registrado actualmente 14 especies dentro del pais ...
... Abraham Mijares-Urrutia 1 J. Celsa Señaris 2 & Alexis Arends 1. ... 1996), descri... more ... Abraham Mijares-Urrutia 1 J. Celsa Señaris 2 & Alexis Arends 1. ... 1996), descrita con base en un único ejemplar (en esta especie incluimos, tentativamente, a E. goeleti, considerado un sinónimo de E. phelpsorum por Gorzula & Señaris 1998), cuya distribución abarca las cimas ...
Only two species of the microteiid lizard genus Euspondylus (E. acutirostris and E. phelpsorum) h... more Only two species of the microteiid lizard genus Euspondylus (E. acutirostris and E. phelpsorum) had been reported from Venezuela. New records of the poorly known gymnophthalmid lizard Euspondylus acutirostris are reported extending its known range along the Coastal Range and Sierra de Aroa (north-central Venezuela) and Sierra de San Luis (northwestern Venezuela), all records occurring at the cloud forest above 1000 m. Seven body measurements were included and morphological variation is described based on at least 17 new specimens. Sexual dimorphism is determined in, at least, eight characteristics of size and squamation. Specimens were found in epiphytic bromeliads and the ground. The populations from Sierra de Aroa and Sierra de San Luis (only one specimen known from each locality), differ from those of the Coastal Range (supposedly the nominal population) in some morphological and coloration features, suggesting that the former two could represent different taxonomical entities. A new species of Euspondylus is described based on a female (taken within a bromeliad) from Cerro El Humo, Sucre, northeastern Venezuela. It differs from congeners mainly by having keeled scales on the limbs and a very acute snout.
... FEEDING HABITS OF LEPTONYCTERIS CURASOAE IN NORTHERN VENEZUELA ANGELA MG MARTINO,* JAIME 0. A... more ... FEEDING HABITS OF LEPTONYCTERIS CURASOAE IN NORTHERN VENEZUELA ANGELA MG MARTINO,* JAIME 0. ARANGUREN, AND ALEXIS ARENDS ... Bats may show differential use of feeding resources (Whitaker et al., 1996), changes in feeding selection, or ...
... FEEDING HABITS OF LEPTONYCTERIS CURASOAE IN NORTHERN VENEZUELA ANGELA MG MARTINO,* JAIME 0. A... more ... FEEDING HABITS OF LEPTONYCTERIS CURASOAE IN NORTHERN VENEZUELA ANGELA MG MARTINO,* JAIME 0. ARANGUREN, AND ALEXIS ARENDS ... Bats may show differential use of feeding resources (Whitaker et al., 1996), changes in feeding selection, or ...
... ALEXIS ARENDS, FRANK J. BONACCORSO, AND MICHEL GENOUD Centro de Investigationes en Ecologia y... more ... ALEXIS ARENDS, FRANK J. BONACCORSO, AND MICHEL GENOUD Centro de Investigationes en Ecologia y Zonas Aridas, Universidad Nacional Experimental Francisco ... and 2). The lower-critical temperature is 30-320C in each of the three species (Table 1). Below the lower ...
Data on population parameters obtained by the capture-mark-recapture method using a grid with 121... more Data on population parameters obtained by the capture-mark-recapture method using a grid with 121 trapping stations during 13 continuos months, were related to relative indexes of food availability, consumption and preference through Principal Component Analyses. Marmosas population density tends to have a strong and positive correlation to a diet of animal origen when individuals are mainly no-reproductive. Presence of lactating females, as well as the minimal survival rate, also tend to be positively correlated with biomass peaks of Coleoptera, larvae, and ripe fruits of Cactacea species. On the other hand, home range size and arboreal activity showed had no significant correlations to the environmental variables. Marmosas movements are determined by its familiarity of surroundings rather than food availability. To reach conclusive results, further studies must concider quantification of availability, consumption and preference indexes, as well as extention of total time the varia...
... The dominant thorn forest vegetation near the cave includes : columnar cacti (Ste-nocereus gr... more ... The dominant thorn forest vegetation near the cave includes : columnar cacti (Ste-nocereus griseus, Cereus (Subpilocereus) repandus), mesquite (Prosopis juliflora), leguminous trees such as Erythrina velutina and Cercidium praecox, prickly pear (Opuntia (wentiana ...
The moustached bats, Pteronotus davyi, P. personatus, and P. parnellii, and the ghost-faced bat, ... more The moustached bats, Pteronotus davyi, P. personatus, and P. parnellii, and the ghost-faced bat, Mormoops megalophylla (Mormoopidae), are homeotherms with normal to slightly low basal rates of metabolism for mammals of their body mass. They are unable to resist ...
Marmosa is the most species-rich genus of living marsupials, and its members are distributed near... more Marmosa is the most species-rich genus of living marsupials, and its members are distributed nearly all over the available habitats in the Neotropics. M. robinsoni and M. xerophila are two species belonging to this genus. M. robinsoni is spread throughout the Llanos and the rainforest; while M. xerophila is found in semi-arid ecosystems. A very close phylogenetic relationship between these two species has been claimed. In the present paper, our main goal is to measure some population parameters of M. xerophila and study the effects on them caused by the seasonal variability of a semi-arid ecosystem, not only to learn about the species’ natural history but also to estimate the significance of these adaptations, when comparing them to the information already known about M. robinsoni in other ecosystems. The results show that the different parameters which govern the population dynamics of M. xerophila are synchronized with environment variations. This synchronization or seasonality is...
... Abraham Mijares-Urrutia, Alexis Arends R. ... En Venezuela, las lagartijas del género Gonatod... more ... Abraham Mijares-Urrutia, Alexis Arends R. ... En Venezuela, las lagartijas del género Gonatodes Fitzinger, popularmente llamados "Tuqueques" (Rivero-Blanco, 1967), son las mAs divers as entre los gecónidos, habién-dose registrado actualmente 14 especies dentro del pais ...
... Abraham Mijares-Urrutia 1 J. Celsa Señaris 2 & Alexis Arends 1. ... 1996), descri... more ... Abraham Mijares-Urrutia 1 J. Celsa Señaris 2 & Alexis Arends 1. ... 1996), descrita con base en un único ejemplar (en esta especie incluimos, tentativamente, a E. goeleti, considerado un sinónimo de E. phelpsorum por Gorzula & Señaris 1998), cuya distribución abarca las cimas ...
Only two species of the microteiid lizard genus Euspondylus (E. acutirostris and E. phelpsorum) h... more Only two species of the microteiid lizard genus Euspondylus (E. acutirostris and E. phelpsorum) had been reported from Venezuela. New records of the poorly known gymnophthalmid lizard Euspondylus acutirostris are reported extending its known range along the Coastal Range and Sierra de Aroa (north-central Venezuela) and Sierra de San Luis (northwestern Venezuela), all records occurring at the cloud forest above 1000 m. Seven body measurements were included and morphological variation is described based on at least 17 new specimens. Sexual dimorphism is determined in, at least, eight characteristics of size and squamation. Specimens were found in epiphytic bromeliads and the ground. The populations from Sierra de Aroa and Sierra de San Luis (only one specimen known from each locality), differ from those of the Coastal Range (supposedly the nominal population) in some morphological and coloration features, suggesting that the former two could represent different taxonomical entities. A new species of Euspondylus is described based on a female (taken within a bromeliad) from Cerro El Humo, Sucre, northeastern Venezuela. It differs from congeners mainly by having keeled scales on the limbs and a very acute snout.
... FEEDING HABITS OF LEPTONYCTERIS CURASOAE IN NORTHERN VENEZUELA ANGELA MG MARTINO,* JAIME 0. A... more ... FEEDING HABITS OF LEPTONYCTERIS CURASOAE IN NORTHERN VENEZUELA ANGELA MG MARTINO,* JAIME 0. ARANGUREN, AND ALEXIS ARENDS ... Bats may show differential use of feeding resources (Whitaker et al., 1996), changes in feeding selection, or ...
... FEEDING HABITS OF LEPTONYCTERIS CURASOAE IN NORTHERN VENEZUELA ANGELA MG MARTINO,* JAIME 0. A... more ... FEEDING HABITS OF LEPTONYCTERIS CURASOAE IN NORTHERN VENEZUELA ANGELA MG MARTINO,* JAIME 0. ARANGUREN, AND ALEXIS ARENDS ... Bats may show differential use of feeding resources (Whitaker et al., 1996), changes in feeding selection, or ...
... ALEXIS ARENDS, FRANK J. BONACCORSO, AND MICHEL GENOUD Centro de Investigationes en Ecologia y... more ... ALEXIS ARENDS, FRANK J. BONACCORSO, AND MICHEL GENOUD Centro de Investigationes en Ecologia y Zonas Aridas, Universidad Nacional Experimental Francisco ... and 2). The lower-critical temperature is 30-320C in each of the three species (Table 1). Below the lower ...
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