Backyard chicken flocks pose a disease risk for neotropic birds in Costa Rica.

Pathogens of free-ranging chickens create a risk of disease for wild birds, some of which migrate to the United States, as well as potential economic losses for resource-poor farmers. Free-roaming backyard chickens are commonly kept in shade-grown coffee plantations, habitats that attract large numbers of wild birds. The husbandry and pathogen prevalence of backyard chicken flocks in San Luis, Costa Rica, were investigated. Based on serologic evidence, Newcastle disease virus, infectious laryngotracheitis virus, infectious bronchitis virus, chicken anemia virus, and infectious bursal disease virus, as well as both Mycoplasma gallisepticum and Mycoplasma synoviae, appear to be significant diseases of this population, and thus, we consider these backyard chickens potential reservoirs for these diseases. There was no evidence of avian influenza. Interviews, clinical examinations, and microscopic examination of tissues led us to believe that poxvirus is also a significant cause of morbidity and mortality in these chickens. We found that Escherichia coli isolates were resistant against tilmicosin, tetracycline, ampicillin, amoxicillin with clavulanic acid, ticarcillin, and cephalothin, and contained genes considered responsible for conferring tetracycline resistance. Additionally, although production was not measured, we suspect that husbandry and lack of preventative medicine are directly related to the diseases reported, all of which negatively affect production.

A new mite superfamily Cloacaroidea and its position within the Prostigmata (Acariformes).

The external morphology of 2 closely related mite families, Cloacaridae and Epimyodicidae (Acari: Prostigmata), comprising highly specialized endoparasites of vertebrates, is analyzed. These mites exhibit strong regression of many structures ancestrally present in other Prostigmata as a consequence of their endoparasitic mode of life. The relationships of these 2 families with other taxa in the infraorder Eleutherengona are still not clear. Our reinterpretation of the chelicerae as unfused precludes inclusion of this lineage in the Cheyletoidea as proposed previously. A new superfamily, Cloacaroidea superfam, nov., incertae sedis, within the infraorder Eleutherengona is established for these 2 families, and their host-parasite relationships are briefly discussed. A new cloacarid species, Caminacarus dawsoni n. sp., from Graptemys pseudogeographica (Testudines: Emydidae) from the United States is also described.

Museum specimens and phylogenies elucidate ecology's role in coevolutionary associations between mites and their bee hosts.

Coevolutionary associations between hosts and symbionts (or parasites) are often reflected in correlated patterns of divergence as a consequence of limitations on dispersal and establishment on new hosts. Here we show that a phylogenetic correlation is observed between chaetodactylid mites and their hosts, the long-tongued bees; however, this association manifests itself in an atypical fashion. Recently derived mites tend to be associated with basal bee lineages, and vice versa, ruling out a process of cospeciation, and the existence of mites on multiple hosts also suggests ample opportunity for host shifts. An extensive survey of museum collections reveals a pattern of infrequent host shifts at a higher taxonomic level, and yet, frequent shifts at a lower level, which suggests that ecological constraints structure the coevolutionary history of the mites and bees. Certain bee traits, particularly aspects of their nesting behavior, provide a highly predictive framework for the observed pattern of host use, with 82.1% of taxa correctly classified. Thus, the museum survey and phylogenetic analyses provide a unique window into the central role ecology plays in this coevolutionary association. This role is apparent from two different perspectives--as (a) a constraining force evident in the historical processes underlying the significant correlation between the mite and bee phylogenies, as well as (b) by the highly nonrandom composition of bee taxa that serve as hosts to chaetodactylid mites.

Revision of the genus Andreacarus (Acari: Laelapidae) with description of seven new species and a new genus for Australian species formerly placed in Andreacarus.

The mesostigmatid genus Andreacarus Radford, 1953 (Acari: Laelapidae), species of which are obligatory parasites of small mammals, is revised. Andreacarus includes 11 species, four species previously recognized and seven new species described from Madagascar hosts: A. brachyuromys sp. n. from Brachyuromys betsileoensis Bartlett, A. eliurus sp. n. from Eliurus species, A. gymnuromys sp. n. from Gymnuromys roberti Major, A. voalavo sp. n. from Voalavo gymnocaudus Carleton & Goodman, A. nesomys sp. n. from Nesomys rufus Peters-all from nesomyid rodents; A. tenrec sp. n. from Tenrec ecaudatus Schreber (Afrosoricida: Tenrecidae); and A. galidia from Galidia elegans I. Geoffroy Saint-Hilaire (Carnivora: Viverridae). An amended generic diagnosis and key to females are also given. Six species described in Andreacarus from Australian and New Guinean hosts are removed and transferred to the new genus, Juxtalaelaps.

Systematics of the genus Sciurocheyla (Acari: Cheyletidae), parasites of tropical squirrels (Rodentia: Sciuridae).

Two genera of parasitic cheyletid mites, Smileycheles Fain, 1979 (monotypic) and Thryonomycheyla Fain, 1972 (two species), are synonymized with the genus Sciurocheyla Volgin, 1969. An emended diagnosis of the genus Sciurocheyla is provided. Sciurocheyla squamosa (Domrow & Baker, 1963), type species of the genus, and Sciurocheyla camerounensis (Fain, 1979), new combination, are redescribed. Females, males, teleo- and protonymphs of Sciurocheyla funisciurus, new species, collected from Funisciurus pyrrohopus F. Cuvier in tropical Africa are described and illustrated.