The Seville Lab
The Seville Lab
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The Coccidia of the World Project is an effort to create a database for the scientific community that, upon completion, will catalogue all known species of coccidia (Apicomplexa: Eimeriidae), their descriptions, and all biologically relevant material. As part of this project, all published information on coccidia occurring in squirrels (Rodentia: Sciuridae) is being compiled and the taxonomy of these parasites evaluated and revised based on quality of published descriptions and adherence to International Code of Zoological Nomenclature (ICZN) guidelines. Each species description is examined in its chronological order of appearance in the literature and evaluated based on previous descriptions from that host group. The description is then evaluated with regard to the ICZN guidelines and a set of minimal criteria established to support a valid description and the group in question is accepted or rejected as a valid species. The rodent family Sciuridae is comprised of two subfamilies, Sciurinae and Pteromyinae, with the first consisting of 36 genera with 230 species and the second 14 genera with 43 species. To date 57 valid species of coccidia from three genera [Dorisa (1 species), Eimeria (54), Wenyonella (2)] have been described and/or reported from 58 different sciurid species with 47 of these reported from members of the subfamily Sciurinae and 10 from the Pteromyinae. Considering that for many of the 58 sciurid species examined (51 Siurinae, 7 Pteromyinae) only a limited number of hosts from a small geographic region have been sampled, and that there are 215 species that have not been examined at all, it is likely that there is a large number of coccidian species occurring in hosts in this taxon yet to be identified. For example, in a related study in collaboration with the Beringian Coevolution Project (BCP), 136 fecal samples from arctic ground squirrels (Spermophilus parryi) collected in Alaska, USA (N = 90) and Russia (N = 46) were examined for the presence of Eimeria spp. Overall, 118 (87%) animals were passing oocysts and four species were recovered and identified. Eimeria callospermophili (prevalence = 18%) and Eimeria lateralis (19%) were both originally described from the golden-mantled ground squirrel (Spermophilus lateralis) in Arizona, USA. Eimeria cynomysis (24%) was originally described from the black-tailed prairie dog (Cynomys ludovicianus) in Colorado, USA. The fourth and most prevalent species (77%) was Eimeria morainensis, also originally described from the golden-mantled ground squirrel. Interestingly, Alaskan prevalences were higher for E. callospermophili (Alaska = 22% vs. Russia = 9%), E. cynomysis (34% vs. 2%), and E. lateralis (27% vs. 4%) but not E. morainensis (78% vs. 76%). This is the first survey of arctic ground squirrels; thus the identification of these species constitutes new host and geographic records for all eimerians identified. Building on the arctic ground squirrel study above, we are intensifying our collaboration with the BCP. This opportunity is the result of conversations at the 2nd International Workshop on Arctic Parasitology in Rovaniemi, Finland in September, 2003. The objectives of the BCP are to: 1) collect data on mammal and parasite occurrence, distribution, and relative abundance, 2) obtain new collections of mammals and associated parasites which will serve as a basis for comparative morphological, phylogeographic, and phylogenetic studies, 3) archive and loan mammal and parasite frozen tissues for use in molecular analyses of Beringian faunas, 4) continue development of a computerized database that permits assessments of regional diversity and biogeography, and 5) foster international collaborations.
2nd International Workshop on Arctic Parasitology Rovaniemi, Finland Sept. 2003
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This page compiled by R. Scott Seville , last update on 01/04/05 |
