Morphometric variations of laelapine mite (Acari: Mesostigmata) populations infesting small mammals (Mammalia) in Brazil.

The goal of this study was to evaluate the morphometric variation of laelapine populations (Acari, Mesostigmata) associated with neotropical oryzomyine rodents at different geographic localities in Brazil. Three nominal mite species were selected for study, all infesting the pelage of small mammals at different localities in Rio de Janeiro, Espírito Santo, Bahia, and the Federal District, Brazil. To analyse morphometric characteristics, thirty-seven morphological characters distributed across the whole body of each specimen were measured. We use the Analysis of Principal Components, extracting the three first axes and projecting each mite in these axes. Major species level changes in the taxonomy of the host mammals allows an independent examination of morphometric variation of mites infesting a set of distinctly different host species at different geographic localities. Gigantolaelaps vitzthumi and Laelaps differens are associated with oryzomyine rodents of the genus Cerradomys, and consistently showed a tendency to cluster by host phylogeny. Laelaps manguinhosi associated with Nectomys rattus in central Brazil is morphometrically distinct from mites infesting N. squamipes in the coastal restingas of Rio de Janeiro and Espírito Santo. The results obtained here indicate that laelapine mite populations can vary among geographic areas and among phylogenetically related host species. Clearly, the study of these mites at the population level can be an important tool for clarifying the taxonomy of both mites and hosts.

Parasitism of Hylodes phyllodes (Anura: Cycloramphidae) by Hannemania sp (Acari: Trombicuudae) in an area of Atlantic Forest, Ilha Grande, southeastern Brazil.

We studied some parameters of the parasitism by the mite Hannemonia sp. on the endemic frog Hylodes phyllodes in the Atlantic Forest of Ilha Grande (Rio de Janeiro State, Brazil). Prevalence, mean abundance, mean intensity and total intensity of infestation, body regions infected, and host sexual differences in parasitism rate of the larvae of Hannemania sp. on individuals of H. phyllodes were assessed. Prevalence was 86.5% (N = 37; total of 1,745 larvae of Hannemania sp) for male hosts and 91.7% (N = 12; total of 330 larvae) for female hosts, with no significant difference between the sexes. Overall prevalence of Hannemania sp. on H. phyllodes was 87.7%. Mean intensity of infestation in males (54.5 +/- 42.5; range 1-173 larvae) was higher than in females (29.9 +/- 47.6; range 1-166). We conclude that the rates of intensity, abundance, and prevalence of Hannemania larvae parasitizing Hylodes phyllodes at Ilha Grande were considerably high, suggesting that this species of anuran constitutes a relevant host for this mite species to complete its life-cycle in the area. Differences between males and females in infestation rates probably reflect their differential use of space in the forest.

Androlaelaps marmosops (Acari: Laelapidae), a new species associated with the mouse opossum, Marmosops incanus (Lund, 1840) in the Atlantic Forest of Rio de Janeiro State, Brazil

Androlaelaps marmosops, a new species of laelapid mite, is described from the pelage of the mouse opossum, Marmosops incanus (Lund, 1840) (Mammalia: Didelphidae), in two areas of Atlantic Forest of Rio de Janeiro State. Measurements and illustrations are included for females only.

Androlaelaps marmosops, uma nova espécie de ácaro lelapídeo, é descrita associada à pelagem da cuíca, Marmosops incanus (Lund, 1840) (Mammalia: Didelphidae), em duas áreas de Mata Atlântica do Estado do Rio de Janeiro. As medidas e as ilustrações foram feitas apenas para as fêmeas.

Androlaelaps marmosops (Acari: Laelapidae), a new species associated with the mouse opossum, Marmosops incanus (Lund, 1840) in the Atlantic Forest of Rio de Janeiro State, Brazil

Androlaelaps marmosops, a new species of laelapid mite, is described from the pelage of the mouse opossum, Marmosops incanus (Lund, 1840) (Mammalia: Didelphidae), in two areas of Atlantic Forest of Rio de Janeiro State. Measurements and illustrations are included for females only

Androlaelaps marmosops (Acari: Laelapidae), a new species associated with the mouse opossum, Marmosops incanus (Lund, 1840) in the Atlantic forest of Rio De Janeiro State, Brazil.

Androlaelaps marmosops, a new species of laelapid mite, is described from the pelage of the mouse opossum, Marmosops incanus (Lund, 1840) (Mammalia: Didelphidae), in two areas of Atlantic Forest of Rio de Janeiro State. Measurements and illustrations are included for females only.

Androlaelaps rotundus Fonseca (Acari: Laelapidae) associated with akodontine rodents in Paraguay: a morphometric examination of a pleioxenous ectoparasite

A multivariate analysis of morphometric data suggests that the nominally pleioxenous ectoparasite, Androlaelaps rotundus, includes at least three distinct host-associated populations in Paraguay. Where multiple akodontine hosts occur sympatrically, each host species is accompanied by a morphologically distinct mite population. These host-mite associations were consistent across all localities, implying that A. rotundus is a complex of unrecognized species

Androlaelaps rotundus Fonseca (Acari: Laelapidae) associated with akodontine rodents in Paraguay: a morphometric examination of a pleioxenous ectoparasite.

A multivariate analysis of morphometric data suggests that the nominally pleioxenous ectoparasite, Androlaelaps rotundus, includes at least three distinct host-associated populations in Paraguay. Where multiple akodontine hosts occur sympatrically, each host species is accompanied by a morphologically distinct mite population. These host-mite associations were consistent across all localities, implying that A. rotundus is a complex of unrecognized species.

New genus and six new species of chiggers (Acari: Trombiculidae and Leeuwenhoekiidae) collected from small mammals in Argentina.

Argentinacarus. n. gen., is proposed with Argentinacarus expansus, n. sp., off Irenomys tarsalis and Akodon longipilis, as type species. Quadraseta akodonica, off Akodon longipilis and Auliscomys micropus, Colicus sinpretarsus, off Histiotus montanus, Parasecia argentinensis off Phyllotis xanthopygus, Parasecia neuquenensis, off Akodon longipilis, and Andalgalomacarus xanthopyga, off Phyllois xanthopygus and Eligmodontia morgani, are described as new. All specimens were collected in Argentina.

Three new species of Laelaps (Acari: Laelapidae) associated with small mammals in central Brazil.

Three new species of Laelaps Koch are described and illustrated from small mammals in the Federal District of Brazil. Each new species is primarily associated with one species of rodent: L. valdevinoi n. sp. from Calomys tener (Winge); L. fonsecai n. sp. from Rhipidomys mastacalis (Lund); and L. furmani n. sp. from Oryzomys bicolor (Tomes). Two of the new species were previously included under names species, from which they are now separated: L. fonsecai n. sp. from L. paulistanensis Fonseca, 1935; L. furmani n. sp. from L. acuminata Furman, 1972. Descriptions of the three new species are based on the female; the male of L. valdevinoi is also described. Diagnoses are included, providing characteristics by which the new species can be distinguished from previously described South American Laelaps.

Host specificity of Laelaps (Acari: Laelapidae) in central Brazil.

A study of associations between small mammals and ectoparasites in two adjacent nature reserves near Brasilia, Federal District, Brazil, revealed that ectoparasitic mites of the genus Laelaps Koch are host specific. Data on the prevalence and intensity of mite infestations were combined with measures of the reproductive activity of mite populations to estimate the association of each host-mite pair. Twelve morphologically distinct species of Laelaps occurred in monoxenous and oligoxenous associations with the cricetid rodent genera Oryzomys, Nectomys, Rhipidomys, and Calomys. Nine were referred to species recognized at the time of the study; three were described as new species in a recent publication. When mites initially assigned as the same species infested more than one host species, an examination of the morphological variation within and among mite specimens supported the hypothesis that mites infesting different hosts were reproductively isolated populations. Dispersal pathways apparently were restricted, occurring primarily between conspecific individuals. In one instance, two morphologically similar groups of Laelaps paulistanensis Fonseca were associated with two closely related rodent species, Oryzomys fornesi Massoia and O. nigripes (Olfers). Although the data presented here indicate that these two groups of mites are conspecific, further study is warranted.

Two new species of chiggers (Acari: Trombiculidae) from small mammals collected in Brazil.

Two new species of chiggers are described from mammals collected in Fazenda Agúa Limpa, Federal District, Brazil: Trombewingia brasiliensis from Bolomys lasiurus and Parasecia lasiurus from B. lasiurus and Oxymycterus sp.

Two new species of schoengastiine chiggers (Acari: Trombiculidae) from Brazil and rediagnosis of Arisocerus Brennan, 1970.

Colicus spinosus Goff & Gettinger, n. sp., is described from Marmosa agilis. Quadraseta brasiliensis Goff & Gettinger, n. sp., is described from Marmosa agilis, Monodelphis americana, and Oryzomys capito. All specimens were collected in central Brazil. The diagnosis of the genus Arisocerus Brennan, 1970, is corrected to describe the setation of the palpal tarsus as 7BS rather than 6BS as listed in the original description.

Spinturnicid mites (Gamasida: Spinturnicidae) associated with bats in central Brazil.

The results of a survey of spinturnicid mites (Gamasida: Spinturnicidae) infesting bats near Brasília, D.F., Brazil, are presented. One hundred twenty-five bats were collected, representing three families and 15 species. Seven species of spinturnicid mites (genus Periglischrus) were collected from nine species of bats (family Phyllostomidae). Each of the following six species of Periglischrus was associated with a single species of bat: Periglischrus acutisternus Machado-Allison and P. torrealbai Machado-Allison on Phyllostomus discolor Wagner; P. paravargasi Herrin and Tipton on Anoura caudifer (E. Geoffroy); P. caligus Kolenati on Glossophaga soricina (Pallas); P. ojasti Machado-Allison on Sturnira lilium (E. Geoffroy); P. herrerai Machado-Allison on Desmodus rotundus (E. Geoffroy). P. iheringi Oudemans was collected from four species of bats (Artibeus cinereus (Gervais), A. jamaicensis Leach, A. literatus (Olfers), and Vampyrops lineatus (E. Geoffroy]. No spinturnicids were found on Carollia perspecillata (L.) or on molossid or vespertilionid bats.