bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurements of powder flow rate in gas-solids pipe flow based on the static electrification of particles
Authors: Masuda Hiroaki , Matsusaka Shuji , Nagatani Shinji
Published: April 2008

A new measuring method of powder flow rate in gas-solids pipe flow was developed and investigated both theoretically and experimentally. The method is based on the static electrification of particles by their impaction on the inside wall. The powder flow rate was successfully calculated by use of the electric currents generated from the wall to the ground. It was found that the effect of initial charge of particles on the measurement could be eliminated by using two metallic pipes whose inner-surfaces were coated with different materials. It was also found that the powder flow rate and the mean particle charge could be measured simultaneously.
The behaviour of floc in the flocculation of kaolinite clay
Authors: Hameed M.S. , Muhammed T.J. , Sapre A.A.
Published: April 2008

Several experimental runs were performed to investigate the effect of kaolinite particle size, flocculation time, velocity gradient, coagulants dose and initial turbidity on the solid removal and floc size or floc formation of suspended solid. The coagulants used were alum, polyelectrolyte (cationic) or a combination of both. Different classifications of clay particles are used in the present work of grade less than 10, 20 and 40 μm. The particle size of 10 μm at 200 NTU initial water turbidity was used to study the effect of flocculation time, (1-20 min) on floc formation size and flocs number at optimum velocity gradient. The size distribution of flocs was studied as a function of kaolinite concentration in the range 1-3 mg/l at 20 min flocculation time in case of alum and polyelectrolyte. The results are presented graphically by three-dimensional and contour plots showing the floc number as a function of coagulant dose and flocculation time. The results are also plotted to show the required turbidity as a function of velocity gradient and flocculation time at optimum coagulant dose to locate the overall optimum working conditions. It is found from various experimental results that floc size or floc formation and growth are the principal criteria that effect the flocculation process.
Effect of dry grinding on iori-exchange characteristics of synthetic mordenite
Authors: Zhang Q. , Kasai E. , Mimura H. , Saito F.
Published: April 2008

The changes in ion-exchange characteristics of synthetic mordenite ground by a planetary ball mill under dry conditions were investigated using radioisotopes of 137 Cs and 85Sr as tracers. The self-diffusion of Cs+ in the mordenite sample was facilitated in the initial stage of grinding, while it was leveled off for the further operation. The relative amount of Cs+ immediately exchanged in the mordenite sample was gradually styptic to a constant value with increase in grinding time after showing a rapid reduction in amount in the early stages of grinding. High selectivity of the mordenite sample for Cs+ against Sr2+ observed in acidic solution diminished obviously with an increase in grinding time.
Effect of Temperature on the Oxygen Consumption of Lizards from different Climatic Regions
Authors: Al-Sadoon Mohamed K. , Spellerberg Ian F.
Published: April 2008

Oxygen consumption levels and metabolic rate temperature curves of various lizard species from three different climatic regions were examined in relation to ambient temperature. The species used in this research were as follows: Anguis fragilis, Lacerta vivipara, Lacerta agilis (cool temperate species); Blanus cinereus, Podarcis hispanica, Podarcis lilfordi brauni, Podarcis lilfordi lilfordi, Podarcis muralis, Psammodromus algirus, Tarentola mauritanica (warm temperate species); Chalcides ocellatus, Acanthodactylus opheodurus, Acanthodactylus schmidti (desert species). A double chamber volumetric closed system was used to measure the resting oxygen consumption of the lizards. Acute oxygen consumption determinations were made, that is the lizards were not allowed to acclimate to the test temperatures. Interspecific differences in levels of resting oxygen consumption and in the characteristics of the metabolic rate temperature curves were examined in relation to methods of thermoregulation and in relation to the ecology of the respective species. Evidence for "temperature dependent shifts" and "low thermal dependence" was found in the metabolic rate temperature curves of some species. A diminishing Q10 at or below the voluntary body temperatures suggests some degree of metabolic homeostatsis and energy conservation.
The Occurrence of Polymely and Polydactyly in Natural Populations of Anurans of the USSR
Authors: Borkin Leo J. , Pikulik M.M.
Published: April 2008

Various cases of isolated and mass polymely and polydactyly in anurans of the USSR fauna are summarized. Mass polydactylies in frogs Rana arvalis arvalis and Rana lessonae-Rana esculenta as well as in toad Bufo bufo bufo are reported. Classiication of polydactyly types based on X-ray analysis is proposed. Species-specificity and lozalized appearance of mass polydactyly factor(s) are discussed.
Comportement Agonistique et Structure Sociale du Lezard Nocturne Malgache Paroedura pictus (Peters, 1854) (Sauria, Gekkonidae) Etudié au Laboratoire
Authors: Brillet C.
Published: April 2008

Non.ritualised social behaviour patterns of the nocturnal Madagascan gecko, Paroedura pictus are described, and the ritual elements of the agonistic dialogue (approaches, threatening displays, confrontations) are analysed. A repertory of gestures is observed, comparable in its diversity to that of diurnal lizards such as the Iguanidae, as well as some behavioural flexibility. The group structure is a hierarchical one of despotic character. The absence of territorial behaviour in this very aggressive species has been proved experimentally.
On the Development of Electroreceptive Ampullary Organs of Triturus alpestris (Amphibia: Urodela)
Authors: Fritzsch Bernd , Bolz Dorothea
Published: April 2008

The ontogenesis of the organs of the lateral-line system of the alpine newt (Triturus alpestris) was examined with special emphasis on the ampullary organs using resin embedded thick sections. The mechanoreceptive neuromasts and the electroreceptive ampullary organ were indistinguishable prior to hatching. At hatching only few ampullary organs were found around the eye. These organs consist of one or two egg-shaped sensory cells and a few supporting cells. The ratio of ampullary organs and neuromasts changes from 1:15.6 (stage 36) to 1:1.1 (stage 62). The number of unidentifiable organs decreases constantly over this period of time and becomes zero at the oldest stages observed. Besides an absolute numerical increase in both types of organs both grow by increasing the number of cells per organ. Comparison with the development of the ampullary organs in catfish shows a striking similarity which suggest either similar functional constraints acting on both catfish and newts or can be interpreted as an indication of homology of both types of organs.
A Taxonomical Survey of the Mountains Frogs of Anatolia
Authors: Baran Ibrahim , Atatür Mehmet K.
Published: April 2008

The aim of this survey is to establish systematical positions of the mountain frogs of Anatolia. Our material was obtained from 24 different populations; 18 populations, of which we have a sufficient number of specimens, are compared biometrically. Due to insufficient number of available specimens, it was not possible to establish properly the taxonomical positions of populations from Artvin and Hakkâri regions. Newer and richer material should be studied from the said localities to clear their taxonomical status.
Régime Alimentaire d'une Population de Lézard des Murailles, Podarcis muralis (Laurent, 1768) dans le Sud-Ouest de la France
Authors: Mou Yung-Ping , Barbault Robert
Published: April 2008

Diet and its variations as a function of time and of lizard size were studied in a natural population of Podarcis muralis in the south-west of France during 1980 and 1981. The taxonomic diversity of the ingested food items, the wide range of prey size, the absence of a close relationship between prey and predator size, and the seasonal and interannual variation of the composition of the diet emphasize the alimentary opportunism of this lizard species. Such opportunism is supposed to be related to the ecological conditions of the studied population, which include high population density, low prey productivity within the biotope, unpredictable variability of prey abundance, and low interspecific competitive pressure.
Sex Recognition by Males of the Lizard Lacerta vivipara: An Introductory Study
Authors: Bauwens Dirk , Nuijten Kees , van Wezel Henk , Verheyen Rudolf F.
Published: April 2008

The role of colour pattern and odiferous cues in sex identification by adult males of the lizard Lacerta vivipara was examined by observing their behavioural response towards several types of introduced conspecific adults. Reproductive males courted both receptive and non-receptive adult females. In addition, they courted introduced males that were painted to mimic the females' colour pattern, indicating that pigmentation functions in sex recognition. Responses of males to females painted as males, untreated females, and uniformly black painted females were identical. This demonstrates that males do not rely exclusively on colour pattern for sex recognition. Odour does not seem to be important as a secondary factor in stimulating courtship. The possible contribution of other stimuli to sex identification is discussed.
Molecular Relationships among Iberian, Moroccan, and South African Lacertid Lizards (Reptilia: Lacertidae)
Authors: Busack Stephen D. , Maxson Linda R.
Published: April 2008

Relationships among representatives of five genera of lacertid lizards from Iberia, Morocco, and South Africa were studied using quantitative micro-complement fixation analysis of serum albumin evolution. Using the albumin molecular clock to establish divergence times we suggest (1) South African Ichnotropis and North African Psammodromus diverged from the lineage representing Lacerta lepida-L. monticola during the Oligocene, (2) South African Pedioplanis and Heliobolus diverged from this lineage during the late Miocene, and (3) ancestral representatives of L. andreanszkyi, L. perspicillata and Podarcis hispanica diverged from lineages leading to L. monticola and L. lepida during the mid-Miocene. Radiation within the Palearctic Lacertidae has clearly been extensive, yet fewer than twenty percent of the species in this radiation have been examined biochemically. Until additional data can be gathered, the current classification of the Palearctic Lacertidae cannot be much improved and we recommend adherence to the taxonomy proposed by Arnold (1973).
Egg and embryo proteins in European newts (genus Triturus) and their taxonomic potential
Authors: Veith Michael
Published: April 2008

Polyacrylamide disc electrophoresis was carried out on water soluble proteins of eggs and embryos of Triturus alpestris, T. boscai, T. cristatus, T. helveticus, T. marmoratus and T. vulgaris. "Major bands" and "minor bands" were defined and species specific phenotyps are described. The patterns of major bands proved to be rather constant during embryonic development up to approximately stage 30 (stretched tailbud stage). The method as used in this study is considered to be practical and relevant for diagnostic studies on Triturus species.
Algunos Aspectos de la Biologia Reproductiva del Sapito Silbador Leptodactylus fuscus (Schneider) (Amphibia: Leptodactylidae)
Authors: Solano Haydée
Published: April 2008

Leptodactylus fuscus nests in the savanna of Calabozo (Guárico, Venezuela) from April to September. Eggs are deposited in foam nests in underground chambers. Details of embryonic and larval development are given. Gravid females contained eggs in three stages of development suggesting more than one clutch per season. Recruiting of young takes place 2½ months after eggs have been laid. There was not significant correlation between the number of eggs and female total length, neither between body volume and volume of ovarian complement. Eleven per cent of the body volumen was occupried by the egg mass. No significant correlation exists between this value and female body size. Peculiarities of the advertisement call of the male and presence of filial cannibalism are discussed.
A remote, insular species of the Lygodactylus somalicus superspecies (Sauria: Gekkonidae)
Authors: Broadley Donald G. , Pasteur Georges
Published: April 2008

A male gecko from the Horn of Africa's arid-country dwelling Lygodactylus somalicus species group has been found in a Zanzibar ground-water forest. The new species, L. howelli, in spite of distinctive traits such as seven preanal pores, no postnasal and heavily pigmented underside in the male sex, indicates that the group is derived from one species with several north-south clines, of which the present-day superspecies L. (somalicus) somalicus/L.(somalicus) howelli is a remnant.
Infrageneric classification and species composition of the anole genera, Anolis, Ctenonotus, Dactyloa, Norops and Semiurus (Sauria: Iguanidae)
Authors: Savage Jay M. , Guyer Craig
Published: April 2008

All valid species of Anolis, Ctenonotus, Dactyloa, Norops and Semiurus are listed by genus and where possible by the infrageneric categories (from most to least inclusive): series, subseries and species groups. An alphabetical index cross-referencing the species names to genus and series is also included.
Sperm morphology of Batrachyla (Anura: Leptodactylidae)
Authors: Garrido Orlando , Pugin Emilio , Jorquera Boris
Published: April 2008

The structure of immature and mature sperm of the three species of Batrachyla were compared by using smears for light microscopy and ultrathin sections for transmission electron microscopy. Minor differences in length and some ultrastructural details support the notion that B. antartandica and B, taeniata are more closely related to each other than to B. leptopus. Comparisons of the sperm of Batrachyla with those of other anurans suggest the sperm morphology may be correlated with broad phylogenetic relationships as well as mode of fertilization.
A new species of collared frog (Anura: Dendrobatidae: Colostethus) from Serrania de Portuguesa, Andes of Estado Lara, Venezuela
Authors: La Marca Enrique
Published: April 2008

A new species of frog of the genus Colostethus (Anura: Dendrobatidae) is described from Andean mountain streams and pools at Parque Nacional Yacambu, Estado Lara, Venezuela. The taxon (Colostethus yustizi sp. nov.) belongs in the Colostethus collaris Group and it is distinguished from members of this monophyletic assemblage by the presence of a dark collar with pale spots, and by its reduced foot web.
On the taxonomic status of Dipsadoboa aulica aulica Günther and D. aulica flavida Broadley and Stevens, with the description of a new subspecies of D. flavida Broadley and Stevens (Boiginae, Serpentes)
Authors: Bødtker Rasmussen Jens
Published: April 2008

Variation in the African marbled tree snake, Dipsadoboa aulica, has been analyzed within the framework of a review of the whole genus. Three forms are most readily distinguished on the basis of coloration and on internal morphology. Within each form a gradual colour change takes place from juveniles to adults. The following taxonomic changes are proposed:
Bones of giant lacertids from a new site on El Hierro (Canary Islands)
Authors: Izquierdo I. , Medina A.L. , Hernández J.J.
Published: April 2008

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.
Allozyme relationships of some frogs (genus Rana) from Yunnan, China
Authors: Li Fanglin  , Green David M. , Sharbel Timothy F.
Published: April 2008

The genetic relationships of four species of frogs, genus Rana, from Yunnan, China, were investigated using starch gel electrophoresis of isozymes. Rana chaochiaoensis, R. pleuraden, R. phrynoides and R. limnocharis, representing four different species groups, were compared to each other and to representative species from other parts of Asia: R. amurensis from eastern Siberia, R. japonica from Japan, and R. nigromaculata from Korea. Twenty-four isozyme loci were reliably detected and scored, of which all but one were variable. R. chaochiaoensis, R. japonica and R. amurensis, all members of the Eurasian "brown frog" group, clustered together as a group although genetic distances were comparatively high. The "pond frogs", R. nigromaculata and R. pleuraden, similarly clustered together. Both R. phrynoides and R. limnocharis were highly divergent from the other species, but R. phrynoides seemed to be more closely affiliated with the "pond frogs" than with the "brown frogs". The data indicate that the highly enigmatic 64-chromosome karyotype of R. phrynoides arose from among 26-chromosome ancestors. The relationships of R. limnocharis cannot be precisely defined. Genetic divergence among Asiatic Rana appears to be very high.
Real vs apparent distributions of dwarf amphibians: Bufo lindneri Mertens 1955 - a case in point
Authors: Clarke B.T.
Published: April 2008

The literature records only four specimens identified as Bufo lindneri Mertens, and gives the distribution of this species as Dar es Salaam, Tanzania and a locality 23 km from Dar es Salaam. The discovery of a further fourteen specimens provides evidence of a wider distribution including S. Tanzania, Malawi and Mozambique. B. lindneri is redescribed on the basis of this new material. It is suggested that specimens of dwarf species have often been overlooked, either because of their size, choice of habitat or cryptic coloration or a combination of these factors, leading to the erroneous conclusion that they are rare, or that the species has a restricted distribution. It is further suggested that dwarf species are of particular biological interest. They may be important as ecological indicator species, as indicators of distinct microhabitats, modes of reproduction and associated behaviours.
Non-random mating by size in the midwife toad Alytes obstetricans: Bigger males carry more eggs
Authors: Raxworthy C.J.
Published: April 2008

The European midwife toad Alytes obstetricans is unusual because the males exhibit parental care. The male carries eggs (possibly from several females) wrapped around his hind limbs until they are ready to hatch. The mating pattern of this species is not random; a significant correlation was found between male snout-vent length and dorsal egg count. Bigger males have larger broods and therefore father more offspring. Because brood size does not appear to affect egg hatching success, larger males may enjoy higher fitness. This non-random pattern of mating may be achieved by male intra-sexual competition, and both male and female mate choice.
Seasonal changes in material and energy balance associated with reproduction in the green lizard, Lacerta viridis, in western France
Authors: Bradshaw S.D. , Saint Girons H. , Bradshaw F.J.
Published: April 2008

Rates of turnover of oxygen, water and sodium were measured in free-ranging and captive Lacerta viridis in western France during their period of reproduction in May, and again in late autumn prior to their entering winter hibernation. Rates of C02 production and turnover of water and sodium in captive lizards showed little significant variation and these animals appeared to be buffered to a large extent from environmental changes, even though they were exposed to external climatic influences. Overall means for rates of CO2 production in free-ranging individuals did not vary statistically between seasons but considerable individual variation was observed during the breeding season in May. The animals could be divided into 'active' and 'inactive' groups on the basis of their rate of CO2 production and other significant differences were apparent between these two groups: 'active' individuals had increased rates of sodium turnover, lower body water contents and lost body mass during the period of observation whereas the 'inactive' individuals gained mass over the same period. These data suggest that not all individuals necessarily participate in the activity associated with breeding in spring in this species and further behavioural studies would seem appropriate in the light of these physiological data. Calculation of the 'Water Effectiveness Index' for this species from the ratio of water to energy turnover suggests that Lacerta viridis is a profligate utiliser of available resources when compared with similar-sized species of lizards inhabiting desert environments.
Embryonic development of the myobatrachine frogs Geocrinia laevis, Geocrinia victoriana, and their natural hybrids
Authors: Gollmann Birgit , Gollmann Günter
Published: April 2008

The Australian frogs Geocrinia laevis and Geocrinia victoriana undergo prolonged embryonic development inside their egg capsules, before hatching as advanced tadpoles. Despite the presence of large amounts of yolk, the course of development follows the typical anuran pattern rather closely, and is essentially identical in the two species and their natural hybrids. We present a modification of Gosner's (1960) staging table, using mainly changes in the eye and the mouthparts to define stages (20 to 26) in a phase of development, when the Gosner table is not applicable to myobatrachine frogs.
The role of the tail in channel passage by the sand skink, Neoseps reynoldsi
Authors: Mushinsky Henry R. , Gans Carl
Published: April 2008

Thirteen sand skinks, Neoseps reynoldsi, were observed and videotaped traversing variously spaced plexiglass channels and spacings of pins to investigate locomotory patterns of a slender elongate lizard, with reduced limbs. Five individuals were recorded both before and after tail autotomy. Neoseps moves its limbs in locomotion on a flat surface; the hindlimbs participate in propulsion and their position, relative to their body, reflects the curvature of the trunk. Distance between pins, width of the plexiglass channel, and surface texture influence locomotory patterns. Individuals move more rapidly in wide channels, and movement is most irregular in channels with sandpaper floors. Whether on a plexiglass or a sandpaper floor, individuals travel more rapidly down the 2cm wide channel than the 1 cm channel. Fewer bends in the trunk in the wider channels may allow for more rapid movement. Autotomy of the tail slows movement on a plexiglass or sandpaper floor. The anterior portion of the tail contributes to the establishment of a static friction site that is jerked toward the head during locomotion, advancing the center of gravity in that direction. From the new site the trunk can be straightened by pushing against the friction site. The posterior portion of a tailless individual slides backward as the trunk is straightened, slowing their forward movement. The backward slide may reflect the lower mass and reduced static friction of the partial tail. In channels, Neoseps uses limbed concertina rather than simple concertina to generate a propulsive force. Evolutionarily, it appears that elongation of the tail and trunk did not incorporate the capacity for lateral undulation; as the curves of the trunk and tail seem preprogrammed and do not adjust to local points of contact.
The dorsal stripe in newt efts: a method for distinguishing Triturus vulgaris and T. helveticus
Authors: Roberts J.M. , Griffiths R.A.
Published: April 2008

Within a few weeks of metamorphosis, a dorsal stripe develops in smooth and palmate newts (Triturus vulgaris and T. helveticus). A method for distinguishing between the efts of these two species using characters based on the dorsal strip is described and evaluated. The method was tested using both experienced and inexperienced observers who, on average, classified 87% of the T. vulgaris and 97% of T. helveticus correctly. No misclassifications were made by any of the observers but a small proportion of the efts could not be classified with confidence into either category because the dorsal stripes were only faintly discernible.
The skeleton of a juvenile Lanthanotus (Varanoidea)
Authors: Rieppel Olivier
Published: April 2008

The cleared and stained skeleton of a juvenile Lanthanotus bomeensis provides additional evidence for the "cervicalization" of an anterior dorsal vertebra, resulting in the 9 cervical vertebrae thought to be diagnostic of the Varanidae. Lanthanotus shows two complete sternal ribs associated with the vertebral segments 10 and 11, and an incomplete sternal rib associated with the 9th segment; Varanus shows three complete sternal ribs associated with the vertebral segments 10, 11 and 12. The loss of a sternal rib associated with the 12th segment is autapomorphic for Lanthanotus. Nine cervical vertebrae may be diagnostic for the genus Varanus only, since Lanthanotus preserves a rudimentary sternal rib associated with the 9th vertebral segment, at least at some stage of its ontogeny. A free carpal "intermedium" is absent (or variably present) in Lanthanotus. The pattern of epiphyseal calcification in the carpus and tarsus of Lanthanotus is described and compared to Varanus.
The status of the races of the graceful crag lizard, Pseudocordylus capensis, from South Africa
Authors: Herselman Y.M. , Mouton P. le F.N. , Van Wyk J.H.
Published: April 2008

To evaluate the taxonomic status of the races of the graceful crag lizard, Pseudocordylus capensis, geographical variation in 44 external morphological characters was determined, using 97 specimens from 31 localities. Two different epiphenotypes predominate in the northern and southwestern parts of the distribution range. These epiphenotypes are, however, connected by a continuum of variation. It is therefore suggested that the recognition of races be abandoned in the formal taxonomy. Several new distribution records for the species are provided.
Residence in water by the newts Triturus vulgaris, T cristatus and T. alpestris in a pond in northern Italy
Authors: Fasola Mauro , Canova Luca
Published: April 2008

The annual cycle of residence in water differed considerably among the three syntopic newts Triturus vulgaris, T cristatus and T. alpestris at a pond in northern Italy. T. vulgaris were resident in water for only short periods, which were used exclusively for reproduction. Adult T cristatus were present in the water for 3-4 months after reproduction, and regained weight during autumn. T. alpestris were present throughout the year; branchiate juveniles and neotenics were more abundant than adults.
Morphological analysis of two Hungarian water frog (Rana lessonae-esculenta) populations
Authors: Gubányi A. , Korsós Z.
Published: April 2008

Two water frog populations, Rana lessonae-esculenta systems, have been studied in Hungary from the morphological point of view. Multivariate analyses of selected morphological measurements based on biochemical identification of the species provide two ratios as possible key characters for determination of the two forms.
Ontogeny of the oral apparatus of the tadpole of Bufo americanus
Authors: Tubbs Lydia O.E. , Stevens Rebecca , Wells Marion , Altig Ronald
Published: April 2008

The development of the oral apparatus of tadpoles of Bufo americanus was described from late embryonic through to metamorphic stages. Although sufficiently detailed developmental studies are not common, especially of species with tooth row formulae greater and less than 2/3, it appears that differences in timing rather than in sequence are the primary interspecific differences. Species with rapid developmental times (e.g. Bufo) seemingly start and complete developmental sequences slightly earlier than species with longer developmental times. Species with labial tooth row formulae greater than 2/3 start development sooner, complete it later and retain mouth parts longer into metamorphosis than species with 2/3 tooth rows. Lentic species tend to form the oral structures later and faster and atrophy the oral apparatus earlier and faster than lotic forms. For these reasons, oral development is often discordant with features of limb development used in staging.
On the acoustic profile of the rattlesnake rattle
Authors: Young Bruce A. , Brown Ilonna P.
Published: April 2008

A survey of the acoustical profile of 74 rattlesnakes, representing 27 taxa was performed. A close relationship was found between the size of the proximal rattle segment and acoustic properties of the rattling sound. No evidence of distinct interspecific variation in the acoustic profile of the rattle was found. The results suggest that measurements of the proximal rattle segment may be useful as a predictor of the sound produced by the snake.
Reproductive biology of the parsley frog, Pelodytes punctatus, at the northernmost part of its range
Authors: Toxopeus A.G. , Ohm M. , Arntzen J.W.
Published: April 2008

The reproductive biology and population dynamics of Pelodytes punctatus were studied at the breeding season over a three year period in a coastal dune system located at the extreme northwestern border of the species' range. Adult population size estimates ranged from about 100 in the first year to 60 in the third year. Males were remarkably sedentary near the pond under artificially provided shelters. Many were observed during the most of the breeding season which lasted from mid-March or the end of March to the end of April or mid-May. Most spawning took place in the second half of March or early April. In two years out of three a second period of spawning involving fewer animals was observed in the first half of May. Both periods of spawning coincided with, or shortly followed, periods of rising median air temperature. Egg-clutches were deposited in the deepest parts of pond, mainly on submerged vegetation not reaching the surface. An average sized clutch contained approximately 360 eggs. Development of the embryos until hatching took from 4 to 14 days, depending on the ambient temperature. Larval development and growth were fast. Recently metamorphosed froglets at a size of around 18 mm were found from the end of May onwards. Juveniles may reach adult size in the autumn of the year that they were born. Adult frogs did not show a strong fidelity to the breeding pond between years. In the study area the population structure of Pelodytes punctatus seems to be best described by a source - sink model in which flourishing populations in the dunes give rise to short lived satellite populations outside the dunes.
Progesterone induces bright orange throat coloration in female Petrosaurus mearnsi
Authors: Cooper William E. , McGuire Jimmy A.
Published: April 2008

Female Petrosaurus mearnsi develop orange throat coloration when gravid. This coloration was induced in the nonbreeding season (late fall) by exogenous progesterone delivered by subcutaneous implantation in Silastic capsules or intramuscular injection. Color change was first apparent after five days of administration. The time course of brightening was similar for the two methods. Color change was first apparent after five days, and was detectable in most females receiving implants after six days. For both routes of administration, maximum brightening usually occurred within three days of the time that brightening was first detected. Following removal of implants or termination of daily injections, the throat coloration of most females had begun to fade within 25 to 30 days. However, two injected females did not fade at all after sixty days and none faded completely to pretreatment coloration. This suggests that endogenous steroid production by early winter is insufficient to induce brightening, but it might maintain some degree of artificially induced brightening. Because progesterone has also been shown to induce orange female coloration in a distantly related phrynosomatid species and two species of crotaphytids, we hypothesize that induction of bright female secondary sexual coloration by progesterone may be a widespread trait in iguanian lizards.
"Scan" behaviour in Podarcis muralis: the use of vantage points by an actively foraging lizard
Authors: Avery Roger , Basker Annabel , Corti Claudia
Published: April 2008

Two adult Podarcis muralis whose normal movements incorporated the flat top of a wall, frequently paused so that they were looking outwards from an edge ("scan" posture), especially during longer (≥9 s) periods immobile. Investigations of the posture on raised wooden platforms in outdoor enclosures, using two juvenile lizards, showed that (1) lizards spent significantly more time on platforms than would be expected from random movement, and this was not because wood is a favoured substrate for basking; (2) lizards which were immobile on platforms spent significantly more time at edges than would be expected by chance; (3) body orientations at 67.5-112.5° to the edge were the most frequent and these were maintained for significantly longer periods than the remaining orientations; exceptions were from 0800-0900 h when orientation was often parallel to the edge facing the sun and from 1200-1300 h with only a thin strip of shade at 45°, into which the lizards fitted themselves. Lizards basking in the laboratory beneath a tungsten bulb at the edge of a raised platform adopted outward-facing orientations when the platform height was ≥6 mm. When presented with a choice between basking more effectively (i.e. rapid heating rate) or adopting the "scan" posture at an edge with a lower heating rate or with no heating, they opted for the former. Podarcis sicula, P. filfolensis, Lacerta viridis and L. vivipara all showed an excess of outward-facing orientations when the basking bulbs were place near edges of platforms, but Psammodromus hispanicus did not. Only the two Podarcis species, however, spent more time on raised platforms than would be expected by chance when basking was possible at many sites in an arena.
The identity of Mantella cowani Boulenger, 1882 and Mantella haraldmeieri Busse, 1981 (Anura: Mantellinae)
Authors: Böhme Wolfgang , Busse Klaus , Glaw Frank
Published: April 2008

The synonymization of Mantella madagascariensis haraldmeieri Busse, 1981 with M. cowani Boulenger, 1882 by Blommers-Schlösser and Blanc (1991) is unjustified. Re-examination of the type material and descriptions demonstrates the specific distinctness of both, regardless the possibility that cowani and other nominal taxa commonly considered as synonyms of M. madagascariensis are actually taxonomically distinct from the latter.
Relations entre la glycémie et l'activité saisonnière chez Vipera aspis L
Authors: Bonnet Xavier , Naulleau Guy
Published: April 2008

Blood glucose levels in Vipera aspis show great variations, both between months during the annual cycle, and between males and females. The seasonal variations are clearly related to climatic conditions, and particularly air temperatures and possibilities for thermoregulation. The blood glucose levels of the snakes are very low during the hibernation period and high in summer. Nevertheless, climatic conditions alone cannot explain changes of blood glucose levels observed during the period when the vipers are active, particularly the peaks measured soon after emergence from hibernation (males in February, females in March). Testicular activation, vitellogenesis and digestion need high body temperatures for long periods, thus the blood glucose level in reptiles chould be the result of a balance between climatic and physiological conditions expressed by the thermoregulatory behaviour. Plasma glucose levels are higher when the body temperatures are high and when the vipers spend more time in the sun (e.g. males in February, females in March); however, hormonal factors probably play a role.
Effects of feeding on set point temperatures and thermoregulatory behaviour in the lizards
Authors: Tosini Gianluca , Jones Scott , Avery Roger
Published: April 2008

Feeding resulted in immediate upward shifts of between 0.62 and 3.00 K in the mean set points at which basking started and ceased (Tbask and Tmove) in P. muralis allowed to thermoregulate beneath tungsten bulbs giving three different levels of radiant heat, except for Tmove in lizards at the highest level (70 mW cm-2 measured in the range 8 000-14 000 nm). Mean bask durations decreased following feeding, but mean forage durations also decreased and the overall times spent basking increased. Values for all four variables declined gradually, returning to pre-feeding levels after 30-50 min. Feeding had no effect on mean heating rates. Feeding in Lacerta vivipara also resulted in increases in set point temperatures, but mean bask durations increased following feeding in this species.
Fat body and liver cycles in the large girdled lizard
Authors: van Wyk J.H.
Published: April 2008

Cordylus giganteus is a large viviparous lizard endemic to the Highveld grasslands of South Africa. Seasonal morphometric changes in fat body mass, liver mass and a carcass condition index in male, female and juvenile C. giganteus are described for a 15 month period. In the adult male and juvenile classes, abdominal fat bodies increase during late summer and autumn followed by a dramatic depletion during winter hibernation. Although that fat body cycles of adult reproducing females are similar to those of males, the magnitude of lipid storage in these females was considerably greater. Adult females showing early vitellogenic activity and significantly larger fat bodies than non-reproductive females. Seasonal liver mass changes paralleled the fat body cycles in all classes. Fat body stores appear to be used by all classes for winter and early spring nutrition. Energy needs during winter vitellogenesis in females and mating activity during spring in males may also benefit from fat body and liver energy stores. The hypothesis that biennial reproduction in females is determined by the magnitude of energy reserves at the onset of vitellogenesis in autumn is upheld.
Non-invasive sex identification of juvenile gopher and desert tortoises (genus Gopherus)
Authors: Burke Russell L. , Jacobson Elliott R. , Griffith Michele J. , Guillette Louis J.
Published: April 2008

Using previously preserved specimens, we attempted to develop multivariate discriminating functions that could accurately identify the sex of hatchling Gopherus agassizii and juvenile G. polyphemus based on external morphometrics. A simple and successful function was determined for G. polyphemus, but not for G. agassizii. The failure in the latter case may have becn due to the use of individuals from morphologically distinct populations.
Reproduction in Agama aculeata aculeata and Agama planiceps planiceps females from Windhoek, Namibia
Authors: Heideman N.J.L.
Published: April 2008

Agama aculeata aculeata and Agama planiceps planiceps females were reproductively active during summer, which is the rainy season in Namibia. Both species were iteroparous; clutch size and relative clutch mass in the smaller A. a. aculeata were significantly larger than in A. p. planiceps. Egg and newborn hatchling size of A. a. planiceps on the other hand were significantly greater than in A. a. aculeata. It is suggested that these differences may have evolved as a result of different strategies which the two species possibly employ to cope with predation pressure, namely, evasion through crypsis in A. a. aculeata and through speed of escape in A. p. planiceps.
Genetic relationships between populations and intraspecific subdivision of Elaphe longissima (Laurenti, 1768) as suggested by plasma protein electrophoresis and DNA fingerprinting
Authors: Lenk Peter , Joger Ulrich
Published: April 2008

Specimens from the whole range of Elaphe longissima were analyzed for geographical variation of plasma proteins and DNA fingerprint loci. Albumins were identical throughout the range of the species, except for Sicilian specimens of E. l. romana which share bands with E. persica rather than with E. longissima. Transferrins indicate that Central European populations originate from the East, whereas Western European populations are indistinguishable from Northern Italian ones. DNA fingerprints reveal a low effective population size in Central European isolates with only few bands that could be informative for intraspecific groupings. Most of the repeated sequences are located on the female w-chromosome.
Les risques de prédation liés à la reproduction chez un Viperidae ovovivipare, Vipera aspis L., d'après les observations visuelles
Authors: Saint Girons H.
Published: April 2008

If one accepts that the number of times that vipers are observed in the field in any given season is an indirect measure of the overall risk of predation run by such diurnal predators hunting by vision, the results obtained in this study show that risk of predation is particularly high in males during the period of mating and in females when pregnant.
Post-hibernation behavior of a population of garter snakes (Thamnophis sirtalis)
Authors: Sexton Owen J. , Bramble Judith E.
Published: April 2008

The post-hibernation breeding activities of a small population of the common garter snake (Thamnophis sirtalis) were followed in the vicinity of their hibernaculum or den in St. Louis Co., Missouri, USA during the springs of 1981-85, inclusive. Individual males could emerge as early as mid-February and remain at the den and its immediate vicinity for three or more weeks. Each day, after elevating their body temperatures, males patrolled the ground surface within 2-3 m of the den entrance. During patrolling activities, males investigated each other at frequent intervals and often returned to re-enter the den briefly. Upon partial re-emergence, one or more males would assume a position such that the head and anterior portion of the body were elevated. This "blocking" activity may be a behavioral mechanism that controls access to the den by competing males and egress by females. Numerous males simultaneously court a single female. The social organization of garter snakes is compared to that typified by lek species and several similarities are noted.
Genetic data support the specific status of the Italian treefrog (Amphibia: Anura: Hylidae)
Authors: Nascetti Giuseppe , Lanza Benedetto , Bullini Luciano
Published: April 2008

Genetic variation at 28 protein loci was analyzed electrophoretically in populations of the Central European treefrog, Hyla arborea arborea, from Italy, Switzerland, Germany and the Balkans. Two distinct population groups were detected, differing at 9 more or less diagnostic loci, one ranging from Sicily to peninsular Italy, northwards to the Italian slope of the Alps (Italian treefrog), the second parapatrically distributed with respect to the first, north of the Alps, east of the Isonzo river, and southwards to the Balkans (H. arborea arborea s.s.). In the area of close contiguity between the two population groups (approximately coinciding with the border between Italy and Slovenia), neither mixed populations nor hybrid individuals were found. However, a number of specimens with introgressed genotypes were detected in both forms in the contact area and its surroundings, possibly as the result of past hybridization events. The lack of present gene exchange in the contact area indicates that the Italian treefrog and H. arborea arborea (s.s.) are distinct biological species. Average Nei's genetic distance between the Italian treefrog and H. arborea arborea (s.s.) is 0.47, corresponding to an estimated time for evolutionary divergence of about 2-3 million years. The Italian treefrog and H. arborea arborea (s.s.) were found to be morphologically very similar, with a single significant difference (tympanum size) among the considered characters; this is larger in the Italian treefrog. The name Hyla italica nomen novum is proposed for the Italian treefrog, as the name Hylaria variegata assigned by Rafinesque (1814) to treefrog specimens from Sicily is unavailable.
Field metabolism of lizards from lower altitude regions of Baja California Sur (Mexico)
Authors: Grenot Claude J. , Galina-Tessaro Patricia , Alvarez-Cardenas Sergio
Published: April 2008

Water flux rate and field metabolic rate of three free-ranging sympatric species of lizards (Uta stansburiana, Urosaurus nigricaudus and Cnemidophorus hyperythrus) were measured in the Cape Region, near La Paz (Baja California Sur, Mexico) using labelled water (3H2O and H2 18O). During the rainy season, the three species consumed the same prey. Caterpillars of Lepidoptera (7.1 ml H2O/g DM) were the most important in volume and mass. The lizards showed high water flux rates, which did not differ from those of non-desert species, but were 2 to 7 times higher than during the dry season. During the dry season the low rates of water flux were basically due to low metabolic rates. The water flux rate of C. hyperythrus in September was two to four times higher than rates in two other populations in the southern part of the Cape region, but the field metabolic rate was similar. Adult size in the El Comitán population (BM = 6.3 g) was larger than that in two Cabo San Lucas populations (BM = 4.4 and 3.9 g). These data suggest flexibility of responses of species and populations to environmental variation.
Energetics, osmoregulation, and food consumption by free-living desert lizards, Ctenophorus (= Amphibolurus) nuchalis
Authors: Nagy K.A. , Bradshaw S.D.
Published: April 2008

The ecophysiology of the agamid lizard Ctenophorus nuchalis was studied near Shark Bay, Western Australia, during three seasons, over four years, in order to evaluate seasonal and year-to-year variation in energy and material balance, and to compare this agamid with similar-sized iguanid lizards. We measured water influx and efflux rates and field metabolic rates with doubly-labelled water, sodium fluxes with radiosodium, and osmotic status (plasma osmotic and ionic concentrations) in free-ranging adults of both sexes, as well as juveniles. Feeding rates were calculated from diet composition information in conjunction with rates of water and sodium intake, and body condition indices were also determined. There were marked seasonal and year-to-year differences in body condition, and in rates of body mass gain or loss, and these correlated with drought periods. Rates of resource use were highest in spring, and declined through summer and autumn, and rates were lowest during 1983, a year having unusually low winter rainfall. Hatchlings, which emerged in autumn, were able to find and capture food resources, even though adults were eating little during that season. The annual pattern of energy, water and salt balance in this agamid lizard is quite similar to that of an equivalent-sized iguanid lizard.
Cost effective drift fences for toads and newts
Authors: Arntzen J.W. , Oldham R.S. , Latham D.M.
Published: April 2008

The construction, cost and performance of toad and newt drift fences and associated traps used at three study sites is described. Fence efficiency, in terms of the capture of animals immigrating to breeding sites, was calculated to lie between 39 and 63% of the estimated breeding population for the common toad (Bufo bufo), and between 45 and 61% for the crested newt (Triturus cristatus). Fences were consistently less efficient at intercepting emigrating animals; less than 10% of toads and between 34 and 40% of newts were captured. Cost and performance of the systems are compared with data from the literature.