Tila M. Pérez

Confirmation of the presence of Amblyomma triste Koch, 1844 (Acari: Ixodidae) in Mexico

Abstract The following Mexican ticks labeled as Amblyomma triste Koch, 1844, were found in the Colección Nacional de Ácaros, Instituto de Biología, Universidad Nacional Autónoma de México: 4 males (M) and 4 females (F), ex cattle, Jun. 19, 1975, Las Pilas (28°49′N 102°00′W), Múzquiz, Coahuila; 1 M and 1 F, host, date and locality as above; 1 M, ex undetermined deer, Oct. 18, 1976, Yécora (28°22′N 108°56′W), Sonora. Both localities are in the Nearctic Zoogeographic Region. The ticks were confirmed as A. triste, thereby corroborating previous statements concerning the presence of this tick in Mexico. The current known distribution of A. triste includes the Neotropical and the Nearctic Zoogeographic Regions. Amblyomma triste is classified in the subgenus Anastosiella Santos Dias, 1963, whose members are difficult to differentiate in any stage. It is hoped that conventional and molecular taxonomic studies of Anastosiella species will help to clarify their range and phylogenetic relationships.

A SURVEY OF SELECTED PARASITIC AND VIRAL PATHOGENS IN FOUR SPECIES OF MEXICAN PARROTS, AMAZONA AUTUMNALIS, AMAZONA ORATRIX, AMAZONA VIRIDIGENALIS, AND RHYNCHOPSITTA PACHYRHYNCHA

Abstract Isolated populations of four species of Mexican parrots were sampled for evidence of selected pathogens of concern in birds originating in Latin America. Data were collected between June and September 1997, and ectoparasite collection was repeated with Rhynchopsitta pachyrhyncha in September 2000. Serum samples from nine Amazona oratrix, 10 Amazona viridigenalis, 6 Amazona autumnalis, and 25 R. pachyrhyncha chicks were screened for neutralizing antibodies to psittacid herpesvirus and avian influenza and for antibodies to paramyxovirus serotypes 1 and 3. Chicks were also examined visually for fecal parasites and ectoparasites. All serologic and fecal parasite tests were negative. Ectoparasites included ticks, Ixodidae; mites, Ornithonyssus sylviarum; fleas, Psyttopsylla mexicana; lice, Paragoniocotes mexicanus, Heteromenopon sp., and Psittacobrosus sp.; and bugs, Ornithocoris sp. This study provides baseline information to guide future health studies.

Application of ITS-2 sequences as markers for identification and phylogenetic inference within the genus Geomylichus (Acari: Listrophoridae).

Abstract.Phylogenetic relationships among 18 samples from nine nominal species of Geomylichus (Acari: Listrophoridae), were analyzed based on internal transcribed spacer 2 (ITS 2) sequences, Prolistrophorus sp. was used as an outgroup. Maximum likelihood and neighbor-joining analyses indicated that Geomylichus is formed by at least three internal clades. Genetic distance among Prolistrophorus and Geomylichus was 27.8–35.5%, and among species, populations, and infrapopulations of Geomylichus it was 0.4–21.8%, 0.8–2.4%, and 0.8–1.2%, respectively. Differences between the results of this analysis with conventional taxonomy of the group, as well as the overlapping of genetic distances among species, populations, and infrapopulations, suggest that the definition of species within Geomylichus deserves reconsideration. For example, the recognition of inconsistencies among G. texanus populations associated to different host species, resulting from the molecular analysis, led us to collect new morphological evidence now suggesting that this taxon represents more than one species.

Eggs of feather mite congeners (Acarina: Pterolichidae, Xolalgidae) from different species of new world parrots (Aves, Psittaciformes)

Abstract Eggs of 3 new species of feather mites of the genus Genoprotolichus Gaud & Atyeo (Pterolichoidea, Pterolichidae) and 3 new species of the genus Protonyssus Trouessart (Analgoidea, Xolalgidae) were taken from 3 species of New World parrots, namely, Aratinga holochlora (Sclater), A. canicularis (L.) and the extinct Conuropsis carolinensis (L.). Among congeners, egg shape and ornamentation were similar, and oviposition sites were identical.

The Dermacentor (Acari, Ixodida, Ixodidae) of Mexico: hosts, geographical distribution and new records

Abstract Distribution and host data from published literature and previously unpublished collection records are provided for all nine species of the Holarctic tick genus Dermacentor that are known to occur in Mexico, as well as two species that may occur there. Parasite-host and host-parasite lists are presented, together with a gazetteer of collection localities and their geographical coordinates.

The genus Geomylichus Fain (Acari: Listrophoridae) from Mexico, with descriptions of four new species

Abstract From heteromyid rodents collected on the Mexican Plateau, new and named species of Geomylichus Fain (Listrophoridae) were found. Commensal prevalence, intensity, mean intensity and microdistribution are given for each association. Four new species are described, each from a different subspecies or species of Chaetodipus Merriam (Heteromyidae): G (Geomylichus) nelsoni n. sp. from Chaetodipus nelsoni nelsoni (Merriam); G. (G.) durangoensis n. sp. from Chaetodipus nelsoni canescens (Merriam); G. (G.) penicillatus n. sp. from Chaetodipus penicillatus eremicus (Mearns); G (G.) hispidus n. sp. from Chaetodipus hispidus zacatecae (Osgood). Additionally, new host records and new range extensions for five namedspecies of Geomylichus from the Mexican Plateau are given.

Experimental and molecular approximation to microbial niche: trophic interactions between oribatid mites and microfungi in an oligotrophic freshwater system

Mite-fungal interactions play a key role in structuring core ecosystem processes such as nutrient dynamics. Despite their ecological relevance, these cross-kingdom interactions remain poorly understood particularly in extreme environments. Herein, we investigated feeding preferences of a novel genetic lineage of aquatic oribatids obtained from an oligotrophic freshwater system in the Cuatro Ciénegas Basin (CCB) within the Chihuahuan Desert, Mexico. During in vitro diet preference bioassays, transient aquatic microfungi (Aspergillus niger, Talaromyces sp., and Pleosporales sp.) recovered from the same mesocosm samples were offered individually and simultaneously to mites. Gut content was analyzed using classic plating and culture-independent direct PCR (focusing on the fungal barcoding region) methods. Our results indicated that oribatids fed on all tested fungal isolates, yet the profusely developing A. niger was preferentially consumed with all fungal components being digested. This feeding habit is particularly interesting since A. niger has been reported as an unsuitable dietary element for population growth, being consistently avoided by mites in previous laboratory experiments. It is possible that our mites from the CCB have adapted to exploit available resources within this oligotrophic site. This work confirms the trophic relationship between microfungi and mites, two rarely investigated major components of the microbial community, shedding light on the niche dynamics under low-nutrient conditions.

Micropsittophagus n. gen., a new feather mite genus (Astigmata: Pterolichidae) from the green pygmy parrot, Micropsitta finschi (Psittaciformes: Psittacidae)

Abstract A new feather mite, Micropsittophagus atyeoi n. gen., n. sp., belonging to the Psittophagus generic group of the subfamily Pterolichinae (Pterolichoidea: Pterolichidae), is described from the green pygmy parrot, Micropsitta finschi (Ramsay, 1881) (Psittacidae: Psittacinae). This is the first description of a pterolichine from pygmy parrots, the tribe Micropsittini. In comparison to other known genera of the Psittophagus group (Nymphicilichus, Psittaculobius and Psittophagus) the new genus is characterized by several archaic features. In both sexes of the genus Micropsittophagus, the internal vertical setae are present; in the females, the pair of subtegumental sclerotized structures in the sejugal region is rudimentary and the pair in the opisthosomal region is absent.