A new species of Hannemania (Trombidiformes: Leeuwenhoekiidae) parasitizing the endemic and endangered frog, Atelognathus reverberii (Anura: Batrachylidae) from Argentinian Patagonia*

MARIO ESPINOZA-CARNIGLIA; FERNANDO JACINAVICIUS; RICARDO BASSINI-SILVA; MARIA CAROLINA SILVA-DE LA FUENTE; NICOLAS KASS; MARTIN MIGUEL MONTES; LUCILA MORENO; MAARCELA LARESCHI

Congreso; XVI International Congress of Acarology; 2022

Chigger mites of the genus Hannemania Oudemans 1911 (Acari: Leeuwenhoekiidae) are subcutaneous parasites ofamphibians. To date, 28 species have been reported from the Americas and Oceania. In Argentina, only six species havebeen recorded: H. achalai Alzuet & Mauri 1987, H. argentina Lahille 1927, H. edwardsi Sambon 1928, H. hobdayiSambon 1928, H. minor Alzuet & Mauri 1987 and, H. samboni Ewing 1931. Those species were recorded parasitizingfrogs of the genera Bufo Garsault (Bufonidae), Hypsiboas Wagler (Hylidae), Leptodactylus Fitzinger (Leptodactylidae),Nannophryne Günther (Bufonidae), Odontophrynus Reinhardt & Lütken (Odontophrynidae) and, Pleurodema Tschudi(Leptodactylidae). Most of these records are from the northern, northeastern and Andean regions in Argentina. InArgentinean Patagonia, the Meseta de Somuncurá is a protected natural area of great biological interest due to the strongendemism of fauna and flora (at least 14 endemic species). Only, H. hobdayi and H. samboni have been described fromArgentinean Patagonia. The endemic Laguna Raimunda frog, Atelognathus reverberii (Cei) (Anura: Batrachylidae), isan endangered species with a distribution in the semi-permanent volcanic clay lagoons of Meseta de Somuncurá. Theecological characteristics of A. reverberii populations make it vulnerable to habitat degradation and parasitic diseases.This study aimed to describe a potentially new species of Hannemania collected as a parasite of A. reverberii in Mesetade Somuncurá, Río Negro, Argentina. A sample of 11 mites was cleared in lactophenol solution, slide-mounted in Hoyer’smedium, and observed using an optical microscope with Phase contrast and DIC. The mites have a palpal formula thatdiffers from those of the previously described Hannemania species from Argentina and the rest of South America. Theyalso differ from the related species in the number of eupathidia on the genu of leg I (σ) and the number and arrangement ofdorsal opisthosomal setae. We consider that the species morphological differences and geographic isolation are sufficientto propose a novel species of the genus Hannemania. Herein, we present the first record of Hannemania parasitizing A.reverberii. As this amphibian is considered endangered, this novel species of Hannemania is probably threatened. Thisstudy contributes to the knowledge of this parasitic mite. In future studies, it will be necessary to consider molecular dataof Argentinian Hannemania species to achieve a better understanding of the systematics of the genus.