Trichorhina anhanguera, Campos-Filho & Araujo & Bichuette & Trajano & Taiti, 2014

Campos-Filho, Ivanklin Soares, Araujo, Paula Beatriz, Bichuette, Maria Elina, Trajano, Eleonora & Taiti, Stefano, 2014, Terrestrial isopods (Crustacea: Isopoda: Oniscidea) from Brazilian caves, Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 172 (2), pp. 360-425 : 408

TRICHORHINA ANHANGUERA CAMPOS- FILHO, ARAUJO & TAITI SP. NOV.

FIGURES 34–36, 40

Type material

Holotype: ♂, Brazil, Minas Gerais, Morro do Pilar, Gruta MP-10, 20°15′54″S, 43°53′13″W, 13–17 February 2012, leg. R. Bessi ( MZUSP 27543 ).

Paratypes: Two ♂, same data as holotype ( MZUSP 27544 ) ; one ♂, one ♀, same locality and collector, 28 February 2012 ( MZUSP 27545 ) ; one ♂, two ♀, same data ( MZUSP 27546 ) .

Etymology

The new species is named after the Tupi myth of Anhanguera, which means ‘old devil’, protector of animals against hunters.

Description

Maximum length: ♂, 4 mm; ♀, 4.5 mm. Body outline as in Figure 34A. Colourless body. Dorsum covered with fan-shaped scale setae ( Fig. 34E). One line of noduli laterales inserted more or less at the same distance from the lateral margin of pereonites; b/c and d/c coordinates as in Figure 34B. Cephalon ( Fig. 34C,D) with no lateral lobes; no frontal line, suprantennal line straight; eyes absent. Pleon ( Fig. 34A) slightly narrower than pereon, epimera of pleonites 3–5 well developed, falciform. Telson ( Fig. 34F) with distal part triangular, concave sides and rounded apex. Antennule ( Fig. 34G) of three articles, distal article with about ten apical aesthetascs. Antenna ( Fig. 34H) with flagellum as long as fifth article of peduncle, second flagellar article about three times as long as first, apical organ short. Mandibles ( Fig. 35A,B) with molar penicil consisting of a single unbranched seta, left mandible with 2 + 1 penicils and right mandible with 1 + 1 penicils. Maxillule ( Fig. 35C) outer branch with 4 + 5 teeth, all simple; inner branch with two short penicils and a short point on outer margin. Maxilla ( Fig. 35D) with setose and bilobate apex; outer lobe about four times as wide as inner lobe, subquadrate with distal margin straight. Maxilliped ( Fig. 35E) basis rectangular, with sparse triangular scale setae; endite with one seta overpassing distal margin, and distal margin straight, bearing two hooks. Uropod ( Fig. 35F) exopod distinctly longer than endopod; insertion of endopod slightly proximal to that of exopod. Pereopod dactylus with long inner claw, ungual and dactylar seta with simple apex reaching tip and middle of outer claw, respectively ( Fig. 35G).

Male: Pereopods 1–3 carpus and merus with a brush of piliform setae on sternal margin. Pereopod 7 ( Fig. 36A) ischium with sternal margin slightly concave. Genital papilla as in Figure 36B. Pleopod 1 ( Fig. 36C) exopod ovoidal; endopod tapering, with no peculiar modification at apex. Pleopod 2 ( Fig. 36D) exopod triangular, outer margin concave and bearing two setae; endopod longer than exopod, with almost parallel sides, and acute apex. Pleopods 3–5 exopods as in Figure 36E–G.

Remarks

Among the 19 species of Trichorhina presently known from Brazil ( Souza et al., 2011), only two species are known to be blind and colourless: Trichorhina pittieri ( Pearse, 1921) and T. brasilensis . Trichorhina anhanguera sp. nov. is readily distinguishable by the shape of the male pleopod 1 exopod, ovoidal without any posterior lobe. In having the molar penicil of the mandible consisting of a single unbranched seta, the new species resembles Trichorhina lenkoi Souza, Araújo & Campos-Filho, 2011 , Trichorhina macrops Souza-Kury, 1993 , Trichorhina myrmecophila Souza, Araújo & Campos-Filho, 2011 , Trichorhina orensis Souza, Araújo & Campos-Filho, 2011 , Trichorhina paraensis Souza-Kury, 1997b , and Trichorhina sexdens Souza, Araújo & Campos-Filho, 2011 . It differs from these species in the lack of eyes, number of aesthetascs of the antennule, and shape of male pleopod 1.