Contribution to the knowledge of oribatid mites of the genus Austrocarabodes (Acari, Oribatida, Carabodidae) of Madagascar

This work includes taxonomic and faunistic data on carabodid mites (Oribatida, Carabodidae) collected from the Montagne d'Ambre National Park, North Madagascar. A new species of the genus Austrocarabodes is described; A. madagascarensis n. sp. differs from A. similis and A. spathulatus by the presence of foveolae on the body surface. Supplementary descriptions of Austrocarabodes parapustulatus Mahunka, 2009 and A. planisetus Mahunka and Mahunka-Papp, 2011 which were originally described from Madagascar, are presented. The species Austrocarabodes spathulatus Mahunka, 1978 is recorded in Madagascar for the first time.


Introduction
This work is based on oribatid mite (Acari, Oribatida) material, which was collected from the Montagne d'Ambre National Park (Madagascar), and includes data on the family Carabodidae. In the course of taxonomic identification we found four carabodid species, all representatives belonging to the genus Austrocarabodes Hammer, 1966 (the nominative subgenus); of these, one species is new to science. The primary goal of our paper is to describe and illustrate a new species under the name Austrocarabodes madagascarensis n. sp. and to present supplementary descriptions of two other Madagascar species, Austrocarabodes parapustulatus Mahunka, 2009 and A. planisetus Mahunka and Mahunka-Papp, 2011, adding new figures, SEM micrographs and information about some morphological structures and their measurements, identification of leg setae and solenidia and gnathosoma, which will assist with identification of these species in future.

Materials and methods
The studied carabodid mites were collected in the Montagne d'Ambre National Park, North Madagascar during long-term official cooperation between the Moravian Museum in Brno (Czech Republic) and Université d'Antananarivo (Madagascar) in 2010-2014. Specimens (all were studied and measured) were mounted in lactic acid on temporary cavity slides for measurement and illustration. Body length was measured in lateral view, from the tip of the rostrum to the posterior edge of the notogaster. Notogastral width refers to the maximum width of the notogaster in dorsal view. Lengths of body setae were measured in lateral aspect. All body measurements are presented in micrometers. Formulas for leg setation are given in parentheses according to the sequence trochanter-femur-genu-tibia-tarsus (famulus included). Formulas for leg solenidia are given in square brackets according to the sequence genu-tibia-tarsus.
Drawings were made with a camera lucida using a Leica transmission light microscope "Leica DM 2500". SEM micrographs were made with the aid of a JEOL-JSM-6510LV SEM microscope.
Integument 3a, 3c, 3d, 4a-d) -Body color brown to dark brown. Body covered by thick layer of gel-like cerotegument and cerotegumental microridges and some microgranules. Body surface partially microtuberculate. In addition, notogaster sparsely foveolate, foveolae (their diameter up to 8) also partially presented on prodorsum (in basal part and as one pair of longitudinal rows in inner parts of lamellae), on lateral sides of prodorsum (between lamellae and tutoria and on tutoria), in anterolateral parts of ventral plate (pedotecta I and regions close to subcapitular mentum), in anogenital region (posterior and lateral to genital aperture, anterior and lateral to anal aperture, and as one row close to circumventral ridge), and on antiaxial sides of all leg femora and of trochanters III, IV. Epimeral region with some muscle sigillae.
Legs ( Table 1. Famulus of tarsi I short, erect, blunt-ended. Solenidion φ 1 on tibiae I very long, setiform; other solenidia shorter, thickened, blunt-ended to bacilliform. Seta l" on femora I, II and l' on femora III and genua III thickened, seta l" on genua I, II phylliform.    Type deposition -The holotype and three paratypes are deposited in the collection of the Senckenberg Institute, Görlitz, Germany. Twelve paratypes are deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia. All specimens are preserved in ethanol with a drop of glycerol.
Etymology -The name of the new species, madagascarensis, refers to the place of origin, Madagascar.
Remarks -In the presence of dilated mediodistally rostral setae and long, narrowly phylliform (with short attenuate tips) notogastral setae, Austrocarabodes madagascarensis n. sp. is morphologically most similar to Austrocarabodes similis Mahunka, 1978 from Mauritius andA. spathulatus Mahunka, 1978 from Réunion, but differs from both by the presence of foveolae on the body surface (versus foveolae completely absent).
Integument (Figs 5a-c, 6a-d, 7a-e) -Body color light brown to brown. Body covered by thick layer of gel-like cerotegument and cerotegumental microgranules. Body surface partially punctate. In addition, prodorsum (between lamellae) and notogaster tuberculate, tubercles (their diameter up to 8) partially forming polygonal ornamentation on the notogaster; anogenital region (except median part), subcapitular mentum, dorsolateral (bothridia, lateral parts of lamellae) and lateral (between lamellae and tutoria and on tutoria) sides of prodorsum, anterolateral parts of ventral plate (pedotecta I and regions close to subcapitular mentum), and antiaxial sides of all leg femora and of trochanters III, IV foveolate (diameter of foveolae up to 8). Epimeral region with some muscle sigillae.
Material deposition -All specimens (preserved in ethanol with a drop of glycerol) are deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.
Remarks -Our specimens of A. parapustulatus from Madagascar are similar in general appearance to those according to the original description (Mahunka 2009). However, we observed the following: 1. Region between lamellae completely tuberculate in our specimens (versus tubercles presented only mediobasally in the original description). We believe this difference represent intraspecific variability. 2. Mahunka (2009) noted, that "…ventral plate smooth…" (p. 105), but his Figure 31 (p. 106) shows the presence of rounded structures in the anogenital region. We confirm that the anogenital region of the species is indeed foveolate (not smooth).
Integument 10a, 10b, 10d, 10f) -Body color light brown to brown. Body covered by thick layer of gel-like cerotegument and cerotegumental microridges and some microgranules. Prodorsum (between lamellae), notogaster, epimeres (poorly visible under light microscope) and anogenital region densely tuberculate (diameter of tubercles up to 8); subcapitular mentum, lateral sides of prodorsum (between lamellae and tutoria and on tutoria), anterolateral parts of ventral plate (pedotecta I and regions close to subcapitular mentum), and antiaxial sides of all leg femora and of trochanters III, IV foveolate (diameter of foveolae up to 8). Epimeral region with some muscle sigillae.
Material deposition -All specimens (preserved in ethanol with a drop of glycerol) are deposited in the collection of the Tyumen State University Museum of Zoology, Tyumen, Russia.