Species specificity of methyl ketone profiles in the skin lipids of female garter snakes,genus Thamnophis

One of the relatively few vertebrate pheromones to be chemically identified, the female sex pheromone of the red-sided garter snake (Thamnophis sirtalis parietalis) is a series of saturated and monounsaturated methyl ketones contained within female skin lipids. During the breeding season, this pheromone is responsible for eliciting male courtship behaviors and males are able to utilize pheromonal variation to discriminate among females. While the pheromone system of the red-sided garter snake has been the subject of many studies, relatively little is known about the pheromone systems of other garter snakes. Through chemical analyses, we demonstrate that female skin lipids of the red-spotted garter snake (Thamnophis sirtalis concinnus), northwestern garter snake (Thamnophis ordinoides), and plains garter snake (Thamnophis radix) contain similar methyl ketones. The methyl ketone profiles of these snakes differ qualitatively from one another and from the methyl ketone profiles of red-sided garter snakes with differences particularly pronounced between sympatric species. Our results provide evidence that the use of methyl ketones in sexual signaling may be ubiquitous for Thamnophis species and suggest that these compounds could play a role in reproductive isolation between species in this genus.     

IMP-GMP 5'-nucleotidase in reptiles: occurrence in a turtle,a tortoise and three species of snakes

IMP-hydrolyzing activity, which is reactive with goose anti-pig lung IMP-GMP 5′-nucleotidase (c-N-II: EC.3.1.3.5) serum, was detected in extracts from liver, heart, kidney, spleen, stomach, skeletal muscle and lung from several species of reptiles: The values found in liver (U/mg protein) of one animal were: 4.5 for an ammono-ureotelic turtle (Trionyx sinensis japonicus); 3.7 for an ureo-uricotelic tortoise (Testudo elegans); 13–23 for three species of uricotelic snakes: Elaphe quadrivirgata, Elaphe conspicillata and Elaphe climacophora. These findings suggest that in the liver of snakes, c-N-II may participate in the production of uric acid as an end product of amino acid metabolism.     

江西武功山两栖爬行动物资源调查及评价

2001年7月中旬～8月上旬,对江西武功山国家森林公园进行了20多天的野生动植物资源野外考察.公园内现已记录两栖类2目7科25种和爬行类3目9科37种,本次调查增加安福县爬行动物新记录7种：多疣壁虎、中国石龙子、黑背白环蛇、铅色水蛇、灰鼠蛇、乌梢蛇、银环蛇;增加武功山爬行动物新记录23种.动物地理区划属东洋界华中区东部丘陵平原亚区,动物区系组成以东洋界华中区与华南区共有种为主.两栖类东洋界种类占92.00%;生态类型以流水型9种和陆栖-静水型7种占优势.数量优势种为黑斑蛙、中华蟾蜍、黑斑肥螈、泽蛙、棘胸蛙、花臭蛙、华南湍蛙、三港树蟾、镇海林蛙和饰纹姬蛙.爬行类东洋界种类占75.68%,广布种占24.32%.数量优势种有石龙子、蓝尾石龙子、铜蜓蜥、赤链华游蛇、王锦蛇、虎斑颈槽蛇、赤链蛇、红点锦蛇、乌梢蛇、灰鼠蛇、尖吻蝮、竹叶青蛇等.公园内野生动物及其生境受人类干扰破坏大,当地群众保护意识有待增强,就此提出了保护对策.     

New Record of Lycodon liuchengchaoi in Anhui

One juvenile and one adult female wolf snake(Colubridae: Lycodon) were sampled at Yixian and Fuxi, Huangshan, Anhui, China in the summer of 2011 and 2012, respectively. The two specimens were identified as Lycodon liuchengchaoi based on external morphology and molecular data. This is a new reptile record in Anhui Province. In our laboratory, four eggs were laid and three neonates were hatched successfully. This is the first record of the laying and incubation of L. liuchengchaoi eggs. The five specimens were deposited at the Museum of Huangshan University(HUM20140001) and Guangdong Entomological Institute(HB-lcfsp12613, HB-lcfsp-ch1~3).     

A model to predict the thermal reaction norm for the embryo growth rate from field data

The incubation of eggs is strongly influenced by temperature as observed in all species studied to date. For example, incubation duration, sexual phenotype, growth, and performances in many vertebrate hatchlings are affected by incubation temperature. Yet it is very difficult to predict temperature effect based on the temperature within a field nest, as temperature varies throughout incubation. Previous works used egg incubation at constant temperatures in the laboratory to evaluate the dependency of growtProd. Type: FTPh rate on temperature. However, generating such data is time consuming and not always feasible due to logistical and legislative constraints. This paper therefore presents a methodology to extract the thermal reaction norm for the embryo growth rate directly from a time series of incubation temperatures recorded within natural nests. This methodology was successfully applied to the nests of the marine turtle Caretta caretta incubated on Dalyan Beach in Turkey, although it can also be used for any egg-laying species, with some of its limitations being discussed in the paper. Knowledge about embryo growth patterns is also important when determining the thermosensitive period for species with temperature-dependent sex determination. Indeed, in this case, sexual phenotype is sensitive to temperature only during this window of embryonic development.     

Two new species of Parapharyngodon parasites of Sceloporus pyrocephalus,with a key to the species found in Mexico (Nematoda,Pharyngodonidae)

Two new species of Parapharyngodon collected from the intestine of the Mexican boulder spiny lizard Sceloporus pyrocephalus are described. This study increases to 49 the number of valid species assigned to Parapharyngodon worldwide, 11 of them distributed in Mexico. Males of the two new species share the presence of four pairs of caudal papillae, an anterior echinate cloacal lip and the presence of lateral alae; however, both differ from each other in lateral alae extension and echinate cloacal anterior lip morphology. Females of both species have a prebulbar uterus and eggs shell punctuate with pores, characteristics shared with few other species of Parapharyngodon. Both new species differ from other congeneric species in the papillar arrangement, the anterior cloacal lip morphology, the lateral alae extension and total length/spicule ratio. A taxonomic key for the species of Parapharyngodon distributed in Mexico is provided.     

The vitamin D system in iguanian lizards

The apparent plasma concentration of vitamin D binding protein (DBP) in an iguanian lizard, Pogona barbata, and the affinity of this protein for 25-hydroxyvitamin D₃ (25(OH)D₃), 25-hydroxyvitamin D₂ (25(OH)D₂), and 1,25-dihydroxyvitamin D₃ (1,25(OH)D₃) was found to resemble more closely that of the domestic hen than that of the human. The characteristics of Pogona DBP, the pattern of vitamin D metabolites derived from injected radioactive vitamin D₃ and the plasma concentrations of endogenous 25-hydroxyvitamin D (25(OH)D) in a range of iguanian lizards have been examined. The findings suggest that 25-hydroxyvitamin D (25(OH)D) is the major metabolite of vitamin D, and that it may represent the storage form of vitamin D in these species in the same way as in mammals. High concentrations of vitamin D within iguanian embryos and egg yolks suggest a role for this compound in embryogenesis in these species, and perhaps indicates that there is a mechanism for vitamin D delivery to eggs comparable to that found in the domestic chicken.     

The sex ratio of wild Chinese alligators Alligator sinensis

The Chinese alligator Alligator sinensis is one of the most endangered crocodilian species, and typically exhibits temperature-dependent sex determination. It is extremely important to clarify the sex structure of Chinese alligators to implement recovery projects successfully. However, the sex ratio of wild Chinese alligators remains unknown. In this study, we collected 28 years of sex ratio data from Chinese alligators residing in the natural and artificial habitats of Changxing Nature Reserve, China, and examined the differences in the sex ratio dynamics between these two populations. We observed that the sex ratio of wild Chinese alligators is 1 male to 4.507 females, which was significantly lower compared to that of the captive population （1 to 2.040; P 〈 0.001）, and is significantly different to previously documented sex ratios for this species （all P 〈 0.01）. Furthermore, we documented an annually stable （P = 1.000） female-biased sex ratio for wild alligators at hatching [1 male to 4.747 females; 0.174 （0.167~）.182）], in contrast to a dramatically fluctuating sex ratio （P 〈 0.001） in captivity [1 male to 1.674 females; 0.374 （0.246-0.593）], showing a potential mechanism for adjusting the sex structure. Finally, we found that the hatchling sex ratios were similar to that of the population sex ratio （P = 0.748）, with little correlation to air temperature values in the 60-70 day incubation period during the breeding season （July and August; both P 〉 0.05）. Overall, this study indicates that the stabilized female-biased sex ratio of Changxing Chinese alligators might result from selection pressure caused by local mate competition and major inbreeding .     

Freeze-fracture analysis of junctional complexes in the nephron of the garter snake,Thamnophis sirtalis

Summary Zonulae occludentes are shown by freeze-fracture to be pleomorphic along the garter snake nephron. In the neck and proximal segments the occluding junctions are moderately complex with frequent discontinuities in their junctional fibrils. Junctional depth and complexity are maximal in the distal and collecting segments and discontinuities in fibrils are absent. Comparison of these results with similar observations on other tissues indicates that the zonulae occludentes in the neck and proximal segments are intermediate to leaky and that they may be very tight in the distal and collecting segments. These findings suggest that in the garter snake nephron transepithelial flow of fluid may occur primarily by passive diffusion through the zonulae occludentes in the neck and proximal segments and by cell-mediated osmotic flow in the distal and collecting segments. Gap junctions occur only in the proximal tubule and are probably involved in low resistance, intercellular movement of ions.Supported by the National Research Council of Canada. The authors wish to acknowledge the generous provision of freeze-fracture facilities by Dr. M.W. Brightman, NINDS, National Institutes of Health, Bethesda, Maryland, U.S.A.