Host specificity among the helminth parasites of four species of snakes

1980 ◽  
Vol 58 (5) ◽  
pp. 929-930 ◽  
Author(s):  
Manfred E. Rau ◽  
David M. Gordon
Keyword(s):  
Host Specificity ◽  
Thamnophis Sirtalis ◽  
Helminth Parasites ◽  
Nerodia Sipedon ◽  
Snake Species

The helminth parasites of 141 snakes were collected. The nematode Rhabdias fuscovenosa was found in all snake species except Nerodia sipedon, whereas Cosmocercoides dukae was restricted to Storeria dekayi. The trematodes Zeugorchis aequatus and Lechriorchis primus occurred only in Thamnophis sirtalis, whereas Dasymetra nicolli infected only N. sipedon. Pneumatophilus variabilis primarily parasitized N. sipedon but was occasionally found in T. sirtalis. Mesocercariae of Alaria sp. were found in all species except S. dekayi. The cestodes Ophiotaenia sp. and Cylindrotaenia sp. were found in N. sipedon and T. sirtalis, respectively.

Habitat use in basking Northern water (Nerodia sipedon) and Eastern garter (Thamnophis sirtalis) snakes in urban New Jersey

2004 ◽  
Vol 7 (1) ◽  
pp. 17-27 ◽  
Author(s):  
Joanna Burger ◽  
Christian Jeitner ◽  
Heather Jensen ◽  
Megan Fitzgerald ◽  
Stacey Carlucci ◽  
...  
Keyword(s):  
New Jersey ◽  
Habitat Use ◽  
Thamnophis Sirtalis ◽  
Nerodia Sipedon

scholarly journals Staying warm is not always the norm: Behavioural differences in thermoregulation of two snake species

2021 ◽  
Author(s):  
Danilo Giacometti ◽  
Katharine Yagi ◽  
Curtis R Abney ◽  
Matthew P Jung ◽  
Glenn Jeffery Tattersall
Keyword(s):  
Life Histories ◽  
Laboratory Data ◽  
Integrative Approach ◽  
Thamnophis Sirtalis ◽  
Temperature Sensitive ◽  
Thermal Biology ◽  
Snake Species ◽  
Active Nature ◽  
Thermal Preferences ◽  
Insight Into

Thermal biology research compares field with laboratory data to elucidate the evolution of temperature-sensitive traits in ectotherms. The hidden challenge of many of these studies is discerning whether animals actively thermoregulate, since motivation is not typically assessed. By studying behaviours involved in thermoregulation, we can better understand the mechanisms behind body temperature control. Using an integrative approach, we assess thermoregulatory and thermotactic behaviours of two sympatric snake species with contrasting life histories, the generalist Thamnophis sirtalis sirtalis (Linnaeus, 1758) and the semi-fossorial Storeria occipitomaculata occipitomaculata (Storer, 1839). We expected that thermoregulatory behaviours would be optimised based on life history, in that T. s. sirtalis would show higher evidence for thermally-oriented behaviours than S. o. occipitomaculata due to its active nature. Thamnophis s. sirtalis actively thermoregulated, had higher thermal preferences (29.4 ± 2.5 vs. 25.3 ± 3.6°C), and was more active than S. o. occipitomaculata, which showed relatively low evidence for thermotaxis. Our results build on the notion that evaluating movement patterns and rostral orientation towards a heat-source can help ascertain whether animals make thermally-motivated choices. Our data give insight into the thermoregulatory strategies used by snakes with different life histories, and maximise the information provided by behavioural thermoregulation experiments.

scholarly journals Parasite specialization from a phylogenetic perspective: a new index of host specificity

Parasitology ◽  
2003 ◽  
Vol 126 (5) ◽  
pp. 473-480 ◽  
Author(s):  
R. POULIN ◽  
D. MOUILLOT
Keyword(s):  
Host Specificity ◽  
Host Species ◽  
Taxonomic Distinctness ◽  
Phylogenetic Distance ◽  
Helminth Parasites ◽  
Phylogenetic Structure ◽  
Additional Information ◽  
History Of ◽  
Using Data ◽  
Index Value

The host specificity of a parasite is not merely a function of how many host species it can exploit, but also of how closely related these host species are to each other. Here, a new index of host specificity is proposed, one that takes into account the average taxonomic or phylogenetic distance between pairs of host species used by a parasite. The index is derived from measures of taxonomic distinctness used in biodiversity studies. It is easy to compute and interpret, ranging from a minimum value of 1 when all host species are members of the same genus, to a maximum of 5, when all host species belong to different classes. The variance of this measure can also be computed, and provides additional information on the taxonomic or phylogenetic structure of the host assemblage. Using data on helminth parasites of Canadian freshwater fishes, we show that the new index, unlike the mere number of known host species, is independent of study effort i.e. the number of published records of a parasite. Although the index and the number of known hosts are not entirely independent statistically, each captures a different aspect of host specificity. For instance, although acanthocephalans infect significantly more host species than trematodes, cestodes or nematodes, there is no difference in the average index value among these 4 helminth taxa, suggesting that the average taxonomic distances between the host species of a parasite do not vary among these higher taxa. We recommend the use of our new index in future comparative studies of host specificity, in particular when the focus is on the evolutionary history of parasites and of their past colonizations of host lineages.

The Harderian gland of two species of snakes: Pseudonaja textilis (Elapidae) and Thamnophis sirtalis (Colubridae)

2003 ◽  
Vol 81 (3) ◽  
pp. 357-363 ◽  
Author(s):  
Susan J Rehorek ◽  
Mimi Halpern ◽  
Bruce T Firth ◽  
Mark N Hutchinson
Keyword(s):  
Gross Anatomy ◽  
Vomeronasal Organ ◽  
Harderian Gland ◽  
Interspecific Variation ◽  
Nasolacrimal Duct ◽  
Thamnophis Sirtalis ◽  
Mucous Cells ◽  
Vomeronasal System ◽  
Snake Species ◽  
Harderian Glands

The reptilian Harderian gland is a poorly understood cephalic structure. Despite the recent assertion that in snakes it may function as part of the vomeronasal system, the Harderian gland has been described in few snake species. In this study we examined the gross anatomy, histology, and ultrastructure of the Harderian gland of two different advanced snake species (Colubroidea): Pseudonaja textilis (Elapidae) and Thamnophis sirtalis (Colubridae). In both species the Harderian gland is a large serous gland whose secretions pass directly into the vomeronasal organ via the nasolacrimal duct. Contrary to previous publications, the Harderian gland in both species studied possesses a specific duct system lined by mucous cells. However, the Harderian glands of these two species differ in shape, the histochemical nature of these mucous secretions, and the ultrastructure of the serous granules. In conclusion, though the Harderian glands of snakes are remarkably conserved morphologically, there is some interspecific variation.

scholarly journals Host specificity and the probability of discovering species of helminth parasites

Parasitology ◽  
2005 ◽  
Vol 130 (6) ◽  
pp. 709-715 ◽  
Author(s):  
R. POULIN ◽  
D. MOUILLOT
Keyword(s):  
Host Specificity ◽  
Host Species ◽  
Animal Species ◽  
Parasite Species ◽  
Biological Properties ◽  
Helminth Species ◽  
Helminth Parasites ◽  
Taxonomic Range ◽  
Using Data ◽  
Species Being

Different animal species have different probabilities of being discovered and described by scientists, and these probabilities are determined to a large extent by the biological characteristics of these species. For instance, species with broader geographical ranges are more likely to be encountered by collectors than species with restricted distributions; indeed, the size of the geographical range is often the best predictor of a species' date of description. For parasitic organisms, host specificity may be similarly linked to the probability of a species being found. Here, using data on 170 helminth species parasitic in freshwater fishes, we show that host specificity is associated with the year in which the helminths were described. Helminths that exploit more host species, and to a lesser degree those that exploit a broader taxonomic range of host species, tend to be discovered earlier than the more host-specific helminths. This pattern was observed across all helminth species, as well as within the different helminth taxa (trematodes, cestodes, nematodes and acanthocephalans). Our results demonstrate that the parasite species known at any given point in time are not a random subset of existing species, but rather a biased subset with respect to the parasites' biological properties.

Sign in / Sign up

Export Citation Format

Share Document