The skull of the Round Island boa, Casarea dussumieri Schlegel, based on high-resolution X-ray computed tomography

The skull of the rare bolyeriid snake Casarea dussumieri is described in detail based on high-resolution X-ray CT data. Bolyeriids are unique in their possession of a separate suborbital ossification and a maxilla subdivided into two movably jointed parts, which may be the result of paedomorphic truncation of the development of the maxilla from multiple ossification centers. Comparison of the skull of C. dussumieri to that of larger booids suggests additional paedomorphic features including reduction of the dorsal lamina of the nasal and prefrontal and reduction of their contacts with the frontal, limited posterior extent of the posterior free process of the supratemporal, and reduction of the coronoid and splenial. The observations herein do not resolve competing phylogenetic hypotheses based on morphology, which either place tropidophiids as the sister-taxon of bolyeriids, Acrochordus and colubroids, or place bolyeriids as the sister-taxon of the other three. But these observations provide no support whatsoever for the heterodox placement of tropidophiids at the base of alethinophidian snakes, as obtained recently with molecular data.     

Breeding of the Trindade Petrel Pterodroma arminjoniana on Round Island, Mauritius

Round Island (19°51'S, 57°47'E), an uninhabited volcanic islet lying 14 miles NNE of the Mauritian mainland, provides locally important breeding grounds for four species of seabirds; the Trindade Petrel Pterodroma arminjoniana , the Wedge-tailed Shearwater Puffinus pacificus , the Red-tailed Tropic Bird Phaethon rubricauda and the White-tailed Tropic Bird Phaethon lepturus. The landing conditions on the island are notoriously difficult and prior to 1975, visits by naturalists had been limited to short stays, a few days at the most. Accounts of the natural history of the island have been made by Vinson (1965), Bullock (1977) and Bullock & North (1984). This paper gives the results of studies on the breeding biology of the Trindade Petrel during two visits to Round Island from 27 July to 2 September 1978, and from 30 July to 18 August 1982.     

Microsatellite Markers to Determine Population Genetic Structure in the Golden Anchovy,Coilia dussumieri

Coilia dussumieri (Valenciennes, 1848) commonly called as golden anchovy, constitutes a considerable fishery in the northern part of both the west and east coasts of India. Despite its clear-cut geographic isolation, the species is treated as a unit stock for fishery management purposes. We evaluated 32 microsatellite primer pairs from three closely related species (resource species) belonging to the family Engraulidae through cross-species amplification in C. dussumieri. Successful cross-priming was obtained with 10 loci, which were sequenced for confirmation of repeats. Loci were tested for delineating the genetic stock structure of four populations of C. dussumieri from both the coasts of India. The number of alleles per locus ranged from 8 to 18, with a mean of 12.3. Results of pairwise F _ST indicated genetic stock structuring between the east and west coast populations of India and also validated the utilization of identified microsatellite markers in population genetic structure analysis.     

Enclosure utilization and activity of Round Island geckos (Phelsuma guentheri)

This study evaluated space use and activity of individually housed Phelsuma guentheri to formulate recommendations for environmental enrichment. Gecko location within small (0.03 m³) and large (0.22 m³) vivaria and substrate use data were collected over five 24 h periods. Thermogradients within each enclosure type were determined by measuring temperature at various heights. From these data, geckos' space use, activity cycle, and substrate preference were calculated in relation to temperature changes and photoperiod. Geckos did not utilize their environment uniformly. Heavily utilized locations contained cage furnishings or hides. Geckos avoided the use of vertical glass walls. Thermogradients were not actively utilized; however, when given the opportunity, geckos would orient towards natural sunlight. Enclosure size did not affect activity cycle, which was nocturnal with crepuscular peaks. Recommendations for enclosure improvement include provision of more furnishings and hides at different thermal levels. An alternate focal heat source other than UV light is recommended to provide warmth without light. Larger enclosures may encourage more uniform use of available space. Transparent glass may not be an appropriate substrate for these geckos. Once recommendations have been implemented, a similar study must be conducted to assess benefit. © 1995 Wiley-Liss, Inc.     

Population structure of an endemic vulnerable species, the Jamaican boa (Epicrates subflavus)

The Jamaican boa (Epicrates subflavus; also called Yellow boa) is an endemic species whose natural populations greatly and constantly declined since the late 19th century, mainly because of predation by introduced species, human persecution, and habitat destruction. In-situ conservation of the Jamaican boa is seriously hindered by the lack of information on demographic and ecological parameters as well as by a poor understanding of the population structure and species distribution in the wild. Here, using nine nuclear microsatellite loci and a fragment of the mitochondrial cytochrome b gene from 87 wild-born individuals, we present the first molecular genetic analyses focusing on the diversity and structure of the natural populations of the Jamaican boa. A model-based clustering analysis of multilocus microsatellite genotypes identifies three groups that are also significantly differentiated on the basis of F-statistics. Similarly, haplotypic network reconstruction methods applied on the cytochrome b haplotypes isolated here identify two well-differentiated haplogroups separated by four to six fixed mutations. Bayesian and metaGA analyses of the mitochondrial data set combined with sequences from other Boidae species indicate that rooting of the haplotypic network occurs most likely between the two defined haplogroups. Both analyses (based on nuclear and mitochondrial markers) underline an Eastern vs. (Western + Central) pattern of differentiation in agreement with geological data and patterns of differentiation uncovered in other vertebrate and invertebrate Jamaican species. Our results provide important insights for improving management of ex-situ captive populations and for guiding the development of proper in-situ species survival and habitat management plans for this spectacular, yet poorly known and vulnerable, snake.     

The effect of joint, radiation and chemical lesions in rats on their reproductive function]

In experiments with rats exposed to the combined radiation and chemical effects it was shown that fertilization of an ovum and the development of fetus did not vary from these indices in the controls. Viability of sucking rat pups isolated from poison did not vary from the controls as well. Sensitivity of posterity to the toxic effect of chlorophos and lindane was found to increase.     

Tongue movements in the common boa (Constrictor constrictor)

Tongue movements were studied in Contsrictor constrictor by direct observation and by analysis of motion pictures. Vertical tongue movements consisted of an invariant sequence of protrusion, oscillation up and down, and retraction. Lateral deviation of the tongue occurred only in the company of vertical movements and was correlated with the direction of movement of the snake's head. Flick cluster duration varied from about 80 ms to about 1 s; variation in oscillation phase duration accounted for 69 per cent of the total variation. Oscillation phase duration varied linearly with the number of flicks in the flick cluster, suggesting that flick cluster duration is determined primarily by the number of oscilations which are carried out at a constant rate.     

The Bryophytes of the King George Island,Antarctica

After examining the moss collections from the King George Island collected by Dr. Wei Jiang-chun and Mr. Li Zhen-pei in 1983–1984 and 1985 separately, we find 7 species of the mosses, which belong to 4 families and 6 genera. Some of them such as the mosses of Calliergon and Drepanocladus favour moist habitats, whereas Andreaea obovata indicates the dry rocky substratum. Barbula unguiculata and Tortula ruralis could suffer non-permanent dry condition. Geographically, except Andreaea obovata and Calliergon stramineum the other mosses are almost cosmopolitans. They probably distributed to the King George Island before Antarctica drifting to the recent position, and the strong wind was also possible to blow the spores of mosses to Antarctica.     

Material properties of the skin of the Kenyan sand boa Gongylophis colubrinus (Squamata, Boidae)

On the basis of structural data, it has been previously assumed that the integument of snakes consists of a hard, robust, inflexible outer surface (Oberhäutchen and β-layer) and soft, flexible inner layers (α-layers). The aim of this study was to compare material properties of the outer and inner scale layers of the exuvium of Gongylophis colubrinus, to relate the structure of the snake integument to its mechanical properties. The nanoindentation experiments have demonstrated that the outer scale layers are harder, and have a higher effective elastic modulus than the inner scale layers. The results obtained provide strong evidence about the presence of a gradient in the material properties of the snake integument. The possible functional significance of this gradient is discussed here as a feature minimizing damage to the integument during sliding locomotion on an abrasive surface, such as sand.     

The vegetation of Cockburn Island,Antarctica

Cockburn Island, off the north-east Antarctic Peninsula, is important in the history of Antarctic terrestrial biology as it was here where the first botanical collections were made by JD Hooker in 1843. These, and a subsequent collection made by IM Lamb one hundred years later, are described here. A much more detailed survey of the vegetation of the island was made in 1989. At least nine moss, 34 lichen, three cyanobacteria and one alga taxa were recorded, and the floristic composition of several distinct communities assessed. The floristically most interesting and diverse sites are on the island's 250 m high plateau which possesses seepage areas and welldeveloped networks of polygons and stone circles. The vegetation is similar to that occurring on the mainly sedimentary deposits and rocks of nearby James Ross and Seymour Islands, but significantly different to that on the more acidic soils and rocks which predominate throughout much of the maritime Antarctic.