Elaphe Research Articles

Correlates between morphology, diet and foraging mode in the Ladder Snake Rhinechis scalaris (Schinz, 1822)

In many vertebrates, foraging mode (active versus sit-and-wait) is tied to some traits of their natural history such as morphology, type of prey, rate of food acquisition, and survival rate. We explore the correlates between some morphological traits of a Mediterranean colubrid and its feeding ecology and the predation risk, by comparing data on teeth number, tail damage, and diet. A large sample (n = 368) of the Ladder Snake, Rhinechis scalaris is used. The species feeds almost exclusively on endotherms, mainly mammals (nearly 95% of the diet in mass), which set R. scalaris among the most stenophagous snakes in the western Palaearctic. There is also a high percentage of motionless prey in the diet (up to 50% in prey mass), such as nestling birds, mammals and bird eggs. The species is so canalised to a diet based on endotherms that it does not follow the general rule in medium-sized snakes of an ontogenetic dietary shift from ectothermic to endothermic prey; juveniles consumed the smallest endothermic animals: nestling small-mammals. The number of maxillary teeth (mean 15.1), the lowest within the former and large genus Elaphe, is likely related to its trophic specialization. Rhinechis scalaris also faces an elevated risk of predation, something general in active searcher snakes compared to ambush foragers, as revealed by many individuals with damaged tails (19.9%), the highest within the Iberian community of snakes. We conclude from indirect evidence (high predation on stationary prey, many individuals with damaged tails) that the species is an active searcher and that this foraging mode influences other natural- history traits (i.e. reproductive habits).

Mice serve as paratenic hosts for the transmission of Caryospora duszynskii (Apicomplexa: Eimeriidae) between snakes of the genus Elaphe

Caryospora duszynskii Upton, Current et Barnard, 1984 was successfully transmitted to snakes of the genus Elaphe by feeding them previously infected mice. Fifty thousand oocysts were orally administered to two mouse strains, BALB/c and Crl:CD-1(ICR)BR, which were subsequently fed to captive-born coccidia-free Elaphe guttata (L.) in two respective independent experiments. Both E. guttata expelled C. duszynskii oocysts in their faeces, beginning on day 18 and 26 post infection (p.i.) and shed oocysts continuously through the end of the experiment, day 230 and 135 p.i., respectively. There were no parasitic stages or lesions in mice, as revealed by histological examination. Experiments proved that rodents serve as paratenic hosts for C. duszynskii. In summary we discuss the life-cycle strategies of Caryospora spp. in reptiles and present three general modes of their development.

Phylogenetic relationships among European ratsnakes of the genus Elaphe Fitzinger based on mitochondrial DNA sequence comparisons

AbstractIn order to elucidate the phylogenetic relationships in European ratsnakes of the genus Elaphe, we analyzed a 597 bp part of the mitochondrial cytochrome b gene of eight West Eurasian and one East Asian species. Lampropeltis served as outgroup. Maximum parsimony and maximum likelihood suggest the existence of four lineages: 1) E. scalaris; 2) the E. longissima species group comprising E. longissima, E. lineata, E. situla, E. hohenackeri, and E. persica; 3) E. quatuorlineata and 4) E. dione as a sister group to 3). Elaphe scalaris is basal and shows no closer affiliation with any other analyzed species. The Middle Eastern E. persica and E. hohenackeri appear basal within the E. longissima group. Elaphe lineata differs by 8% nucleotide substitutions from E. longissima, supporting the hypothesis that both taxa represent distinct species. Elaphe situla is associated with Elaphe longissima and E. lineata. Three analyzed subspecies of E. quatuorlineata are represented by distinct haplotypes. The extent of divergence gives reason to assign species status to the taxon sauromates. Besides, we found two very distinct haplotypes within the range of E. (q.) sauromates, indicating the existence of a third, so far unidentified, species within the E. quatuorlineata complex. The East Asian E. porphyracea clusters with the E. longissima group. This, as well as comparisons with supplementary sequences of Asian Elaphe species, document the multiple origins of European Elaphe. Um die phylogenetischen Beziehungen europäischer Kletternattern der Gattung Elaphe zu erhellen, sequenzierten und analysierten wir ein 597 Nukleotide messendes Stück des mitochondrialen Cytochrom b Gens von acht west-eurasischen und einer ostasiatischen Art. Lampropeltis diente als Außengruppe. Maximum parsimony und maximum likelihood Berechnungen zeigen die Existenz von vier genetischen Linien auf: a) E. scalaris; b) die E. longissima Artengruppe mit E. longissima , E. lineata, E. situla, E. hohenackeri, und E. persica; c) E. quatuorlineata und d) E. dione als Schwestergruppe zu c). Elaphe scalaris nimmt eine basale Position ein und scheint mit keiner untersuchten Art näher verwandt zu sein. Die westasiatischen Arten E. persica und E. hohenackeri sind die Schwestergruppe zu E. longissima, E. lineata und E. situla. Elaphe lineata unterscheidet sich durch 8% Nukleotidaustausche von E. longissima, wodurch der Artstatus von E. lineata unterstützt wird. Elaphe longissima, E. lineata und E. situla bilden eine Abstammungsgemeinschaft. Auch die Haplotypen der drei untersuchten E. quatuorlineata-Unterarten unterscheiden sich so stark, daß Artstatus für das Taxon sauromates zu fordern ist. Darüberhinaus fanden wir im Gebiet von E. (q.) sauromates zwei stark unterschiedliche Haplotypen, die die Existenz einer dritten bislang unidentifizierten Art nahelegen. Die ostasiatische E. porphyracea scheint der E. longissima-Gruppe nahe zu stehen. Dies, sowie der Vergleich mit ergänzenden Sequenzdaten asiatischer Elaphe-Arten, belegt den mehrfachen Ursprung europäischer Elaphe.

A Monograph of the Colubrid Snakes of the Genus Elaphe Fitzinger by Klaus-Dieter Schultz [Review

A Monograph of the Colubrid Snakes of the Genus Elaphe Fitzinger by Klaus-Dieter Schultz [Review

Sarcocystis clethrionomyelaphis n. sp. from Snakes of the Genus Elaphe and Different Voles of the Family Arvicolidae

Sporocysts obtained from the feces of an Aesculapian snake, Elaphe longissima, caught in Germany were administered orally to species of various rodent genera such as Mus, Apodemus, Microtus, Clethrionomys, as well as to 2 different lizard species of the genus Podarcis and the genus Lacerta. Infections developed only in species of the genera Clethrionomys and Microtus. Based on light microscopic observations and by repeated transmission studies, Sarcocystis clethrionomyelaphis is described as a new species. Sarcocysts with a length of up to 1,200-4,500 ,m and a width of circa 70-170 im developed in susceptible rodents after inoculation with sporocysts excreted by experimentally infected species of the genus Elaphe. The cyst wall contained short (roughly 3 im) protrusions. The bradyzoites measured about 10-12 x 2 im. Experimentally infected snakes of the genus Elaphe shed sporocysts measuring 8.7 (8.2-9.4) x 11.5 (11.1-12.3) ,im. These sporocysts proved to be the same size as those originally isolated from the naturally infected Aesculapian snake.

Experimental investigations on the host range of Sarcocystis podarcicolubris

Lizards experimentally infected with S. podarcicolubris sarcocysts were fed to different species of the family Colubridae. Only species of the genus Coluber proved to be suitable definitive hosts and passed sporocysts in their feces. No sporo- cysts were shed by the species of the genus Elaphe, Coronella and Malpolon that were tested. Fecal sporocysts from different species of the genus Coluber were orally administered to numerous lizards of the genera Lacerta, Podarcis and Algyroides. In all experimental lizards, except the controls, sarcocysts of S. podarcicolubris developed.

Reproductive Behavior of the Rat Snakes of Eastern North America, Genus Elaphe

The courtship and mating behavior of the eastern North American rat snakes, Elaphe obsoleta, E. guttata and E. vulpina were compared in a three-year study of captive animals. Reproductive behavior was divided into a triphasic schema: tactile-chase, tactile-alignment, and intromission and coitus. Touch-mount, chase-mount, dorsal advance movement, forward jerking movement, caudocephalic waves, writhe-bump and tail-search copulatory attempt were defined as mutually exclusive motor patterns exhibited by the male. Intraindividual sequence chains were subjected to transition analysis which yielded the following information: 1) the courtship sequence in all three species is not random, 2) the sequence of E. guttata is much less complex than that of E. obsoleta or E. vulpina, 3) the tactile movements of E. guttata are different than those of E. obsoleta and E. vulpina, 4) E. vulpina exhibits coital biting while E. obsoleta shows courtship biting. Interspecific pairings were not successful.

A New Pliocene Snake, Genus Elaphe, from Oklahoma

. 1955. Lampetra zanandreai, a new species of lamprey from northern Italy. Copeia 1955:215-223. , AND W. I. FOLLETT. 1958. Redescription of Lam.petra ayresii (Giinther) of western North America, a species of lamprey (Petromyzonidae) distinct from Lampetra fluviatilis (Linnaeus) of Europe. J. Fish. Res. Bd. Canada 15:47-77. , AND . 1965. Lampetra richardsoni, a new nonparasitic species of lamprey (Petromyzonidae) from western North America. Ibid. 22:139-158. , AND . 1967. The teeth of l mpreys (Petromyzonidae): their terminology and use in a key to the Holarctic genera. Ibid. 24:1067-1075. ZANANDREA, G. 1959. Speciation among lampreys. Nature, Lond. 184:380. 1961. Studies of European lampreys. Evolution 15:523-534.

Responses to chemical stimuli of prey in newly hatched snakes of the genus Elaphe

Naive, isolated, newly hatched Elaphe vulpina vulpina, tested on a variety of animal surface extracts, demonstrated a tongue-flick response rate significantly higher only to newborn mouse extract (representing a common prey class) than to a distilled water control. A second experiment with Elaphe guttata guttata concentrating on the comparison of mouse extract and distilled water accounted for the effect of novel stimulation and revealed a significant, stable difference between extract and control. A preliminary experiment with air-borne odours resulted in a clear instance of predatory behaviour, including constriction, in the presence of mouse odour. The results indicate that newborn Elaphe can differentiate potential prey on the basis of chemical cues alone.

Interspecific Hybridization between Two Snakes of the Genus Elaphe

Interspecific Hybridization between Two Snakes of the Genus Elaphe

Courtship and Mating of the Foxsnake, Elaphe vulpina vulpina

Courtship and Mating of the Foxsnake, Elaphe vulpina vulpina

Notes on Georgia Snakes of the Genus Elaphe

Notes on Georgia Snakes of the Genus Elaphe

Notes on Mexican Snakes of the Genus Elaphe

Notes on Mexican Snakes of the Genus Elaphe