Contribution to the knowledge of Quadraseta pazca (Brennan and Jones, 1964) (Trombidiformes: Trombiculidae), including new host-association and locality records

The Neotropical genus Quadraseta Brennan has 15 valid species associated with small mammals and birds. Quadraseta pazca (Brennan and Jones, 1964) is the type species chosen by Brennan (1970) to describe the genus Quadraseta. This species was originally described parasitizing murids in Argentina and later recorded parasitizing cricetids in two different Brazilian states, Minas Gerais and São Paulo. In this study, we provide a redescription of Q. pazca based on the type series. The following characters separate this species from the others within the genus: palptibia lateral setae branched; adoral setae branched; one pair of clavate trichobothria (si); leg I genu with three solenidia (σ); and the base of microseta (ε) of leg I tarsus is proximal to the base of solenidion (ω). In addition, we also provide new locality and host-association records for this species in Brazil.

Synonymy of Quadraseta brennani Goff & Whitaker, 1984 with Quadraseta antillarum (Brennan, 1967) (Trombidiformes: Trombiculidae)

Chiggers are ectoparasites of vertebrates and can cause trombiculiasis or transmit pathogens to their hosts. In the Neotropical region, the genus Quadraseta Brennan includes 16 valid species. Quadraseta antillarum (Brennan) and Quadraseta brennani (Goff & Whitaker), are morphologically identical and we propose the synonymy of Q. brennani with Q. antillarum, based on examination of both type series. The little big-eared bat, Micronycteris megalotis Gray from Venezuela is recorded as a new host.

New species records of Quadraseta Brennan, 1970 (Trombidiformes: Trombiculidae) in South America

The genus Quadraseta Brennan, 1970 (Trombiculidae) is distributed in South American, with a few records from Central America. The larvae (chiggers) are primarily mammal parasites, with one species from birds. Examination of unidentified material at US National Insect and Mite Collection revealed five species to this genus: Q. brasiliensis Goff & Gettinger, 1989, Q. falconensis Goff & Brennan, 1977, Q. flochi (Brennan & Jones, 1960), Q. mackenziei (Yunker & Brennan 1964), and Q. mirandae Goff & Brennan, 1977. This study resulted in new South American localities and host records for these species.

Evidence of co-parasitism between different species of chiggers (Trombidiformes: Trombiculidae) parasitizing cricetid rodents in Morro Grande Forest reserve, São Paulo state, Brazil

Chigger mites are ectoparasites of terrestrial vertebrates and can even bite humans, causing lesions on their skins. The co-parasitism is gradually being reported for this family, and recent studies have highlighted this relationship worldwide. In Brazil, only some records of chigger species co-parasitizing rodents and lizards in the Pernambuco and Piauí States were done. The present study reports six co-parasitism situations in cricetid rodents collected in the Morro Grande Forest Reserve, Cotia Municipality, São Paulo State, Brazil.