Topographical and numerical study of the idiosomal integumentary structures of the larva of four Neotropical species of Amblyomma Koch, 1844 (Acari: Ixodidae)

Abstract

Integumentary structures of the larvae of Amblyomma longirostre (Koch, 1844), A. parvum Aragão, 1908, A. rotundatum Koch, 1844 and from three populations of A. cajennense (Fabricius, 1787) were studied using light microscopy. A new nomenclature for the localisation of the integumentary structures is proposed. Three types of integumentary structures were identified in the larval idiosoma of the four Amblyomma species: lyrifissures, small glands and large wax glands. These structures were observed isolated or associated over the entire idiosoma, except in the scutum, which lacked lyrifisures and large wax glands. Large wax glands were the most stable within and between the tick species, followed by lyrifissures and small glands. Small glands, although relatively stable, showed the highest number of numerical variations within and between the tick species. Even though there were intra-population variations in the topographical and numerical pattern of some integumentary structures of A. cajennense larvae, there was a definitive pattern for most of the specimens, as showed by the similar modal and mean numbers of integumentary structures per tick side. The patterns of lyrifissures, small glands and large wax glands showed little differences when compared between the four Amblyomma species; however, a few differences were well evident. These differences were sufficient to differentiate larvae of the four species. Thus, we expect that the study of integumentary structures on the larvae of other Amblyomma species will be useful in future taxonomic keys for the identification of Amblyomma larvae from the Neotropical region.

Morphological description of Amblyomma brasiliense Aragão, 1908 (Acari: Ixodidae) larvae and nymphs

“…The idiosoma of A. brasiliense larvae is rounded, with dimensions similar to A. parvum, as measured by Barbieri et al (2007), and chaetotaxy highly similar and conserved among larvae of Amblyomma spp. for idiosoma (exception for tibiotarsus and setae dII on tarsus I).…”

“…Clifford and Anastos (1960) described the presence of four pairs of large wax glands on the idiosoma: one pair located dorsally on the posterior lateral margin of the body, and the others located behind each coxa. Famadas et al (1997) recorded for the first time a pair of these large wax glands on the fifth festoon of A. cajennense larvae and later Barbieri et al (2007Barbieri et al ( , 2008b recorded these pairs in larvae of A. parvum and A. rotundatum and A. pacae like in A. brasiliense larvae. A. longirostre presents these pairs and an additional pair on the fourth festoon like A. ovale larvae (BARBIERI et al 2008a).…”

“…The terminology followed Clifford and Anastos (1960) and Hess and Vlimant (1983) for larval idiosomal chaetotaxy, Barbieri et al (2007) for larval porotaxy and Famadas et al (1997) for palpal and Haller´s organ terminology.…”

Occurrence of ectoparasites on dogs in rural regions of the state of Minas Gerais, Brazil

“…Samples of the ectoparasites were collected and placed in tubes containing 70% alcohol. Ticks, fleas, lice and fly larvae were identified using proper taxonomic keys (ARAGÃO; FONSECA, 1961;FURMAN;CATTS, 1982;GUIMARÃES, 2000;BARBIERI et al, 2007;MARTINS et al, 2010).…”

New records for Amblyomma sculptum (Ixodidae) on non-passerine birds in Brazil

“…Birds were identified according to Sigrist (2007) and classified according to the recommendations of the Brazilian Committee of Ornithological Records (CBRO, 2014). Ticks were identified according to morphological criteria: females (NAVA et al, 2014), larvae (FAMADAS et al, 1997;BARBIERI et al, 2007) nymphs and males (ONOFRIO et al, 2006). All larvae, nymphs and males identified as A. cajennense were considered as A. sculptum for reasons of their geographic origin.…”