Two new troglobitic species of Iansaoniscus from Brazilian caves (Crustacea, Isopoda, Pudeoniscidae) Author Cardoso, Giovanna Monticelli https://orcid.org/0000-0003-2682-1643 Universidade Federal de Lavras (UFLA), Centro de Estudos em Biologia Subterranea, Departamento de Ecologia e Conservacao, Programa de Pos-graduacao em Ecologia Aplicada. Lavras, Minas Gerais, Brazil gmcardoso.bio@gmail.com Author Bastos-Pereira, Rafaela Universidade Federal de Lavras (UFLA), Centro de Estudos em Biologia Subterranea, Departamento de Ecologia e Conservacao, Programa de Pos-graduacao em Ecologia Aplicada. Lavras, Minas Gerais, Brazil Author Ferreira, Rodrigo Lopes https://orcid.org/0000-0003-3288-4405 Universidade Federal de Lavras (UFLA), Centro de Estudos em Biologia Subterranea, Departamento de Ecologia e Conservacao, Programa de Pos-graduacao em Ecologia Aplicada. Lavras, Minas Gerais, Brazil text Subterranean Biology 2022 2022-06-14 43 127 143 http://dx.doi.org/10.3897/subtbiol.43.81308 journal article http://dx.doi.org/10.3897/subtbiol.43.81308 1314-2615-43-127 AAF4E607B43C4797990305BD241F9CF1 0ABD1F3745D1534893F627D7E0BCD8E2 Iansaoniscus paulae sp. nov. Figs 5 , 6 , 7 , 8 Diagnosis. Cephalon with well-developed lateral lobes with round distal margin; frontal shield rounded, weakly developed; pereonite 1 epimeron without dorsolateral furrow; pereonite 1 and 2 without ventral lobes; antennula distal article with two lateral and one apical aesthetascs; third article longer than second; uropod exopod longer than endopod, longer than distal margin of telson. Material examined. Holotype : Brazil • 1 male (mounted in slide); Bahia state , municipality of Itaete , Lapa do Bode cave (WGS84 -12.938889 , -41.062222 ); 26th July 2007 ; RL Ferreira leg.; ISLA 95915 . Paratypes : • 5 females ; same data as holotype ; ISLA 95916. Etymology. The new species is named after Dr. Paula Beatriz Araujo, UFRGS, for her contribution to the knowledge of Brazilian terrestrial isopods. Description. Maximum length: male, 3 mm; female 5 mm. Body outline as in Fig. 5A , colorless, vestigial eyes (Fig. 5A, B ). Cephalon with well-developed lateral lobes, round distal margin; frontal shield rounded, weakly developed (Fig. 5B ). Pereonite 1 epimeron without dorsolateral furrow; pereonites 1 and 2 without ventral lobes (Fig. 5C, D ); pereonite 3-7 with subquadrangular epimera. Pleonites 3-5 with epimera subquadrangular and directed backwards (Fig. 5A ). Telson (Fig. 6A ) slightly wider than long with concave sides, acute apex. Antennula (Fig. 5E ) with three articles, distal article longer than second article, with two lateral and one apical aesthetascs. Antenna (Fig. 5F , 6B ) surpassing pereonite 3 when extended backwards, fifth article of peduncle as long as flagellum, flagellum with three articles; faint suture between second and third, third article longest, aesthetascs on second and third articles. Mandibles (Fig. 6C, D ) with molar penicil of 4 branches, left mandible with 2+1 penicils, right with 1+1 penicils. Maxillula (Fig. 6E ) outer branch with 4 + 5 teeth (two apically cleft); inner branch with two penicils. Maxilla (Fig. 6F ) with bilobate apex, outer lobe wider than inner lobe, rounded and covered with thin setae; inner lobe bearing thick setae. Maxilliped (Fig. 6G ) basis rectangular; palp basal article with two setae distinct in length; endite rectangular, long medial seta, distal margin with two teeth. Pereopods 1-7 (Fig. 7A, B ) merus and carpus with sparse setae on sternal margin; carpus 1 with longitudinal antennal grooming brush, distal setae cleft; dactylar organ and ungual seta simple not surpassing outer claw. Uropod (Fig. 7C ) protopod distal margin and exopod proximal margin with lateral groove; endopod inserted proximally, exopod 1.4 x longer than endopod and distinctly surpassing distal margin of telson. Figure 5. Iansaoniscus paulae sp. nov. Female paratype A lateral view B cephalon, dorsal view C pereonite 1, dorsal view D pereonite 1, ventral view E antennula F antennal flagellum. Scale bars: 0.5 mm ( A, B, D, E ); 0.3 mm ( C ); 0.1 mm ( E ). Figure 6. Iansaoniscus paulae sp. nov. Male holotype A telson and uropod, dorsal view B antenna C left mandible D right mandible E maxillula F maxilla G maxilliped. Scale bars: 0.2 mm. Male : Pleopod 1 (Fig. 7D ) exopod ovoid, twice wider than long; endopod almost four times longer than exopod, distal portion slightly bent outwards, apex with small setae. Pleopod 2 exopod (Fig. 7E ) triangular bearing one seta on outer margin, endopod flagelliform, almost three times longer than exopod. Pleopod 3-5 exopods as in Fig. 7F-H . Figure 7. Iansaoniscus paulae sp. nov. Male holotype A pereopod 1 B pereopod 7 C uropod D pleopod 1 E pleopod 2 F pleopod 3 exopod G pleopod 4 exopod H pleopod 5 exopod. Scale bars: 0.2 mm. Habitat and conservation issues. The Lapa do Bode cave consists of a dolomite cave with 1,430 meters of horizontal projection, with conduits of labyrinthine pattern. It is inserted in an upper unit of the Una geological group of carbonate rocks from the Salitre Formation (Fig. 9 ) ( Auler 2019 ). This cave presents five entrances (Fig. 8B, C ) inserted in a rock wall parallel to the Una River, which flows close to the entrances (Fig. 8A ). Although most of the cave is dry, the cave atmosphere is considerably moist due to water ponds in some inner areas. The temperature inside the cave is around 24.5 °C. The cave has been used for touristic purposes for the last decades, and the areas where individuals of I. paulae sp. nov. were found (inner portions of the cave, quite distant from the entrances) are also visited by tourists. They were observed walking on moist soil (Fig. 8D ) and in some bat guano piles. Although the touristic activities apparently have not been altering intensively the cave features, there is concern that it could impact the species, especially by trampling (by visitors) due to the reduced size of the specimens and absence of structures guiding visitors to walk in specific pathways. The main available food resource is bat guano, that are concentrated in the inner chambers of the cave. It is worth mentioning that the Lapa do Bode cave presents ten cave-restricted species, among springtails, harvestmen, spiders, a beetle, a millipede, a silverfish, a palpigrade and a fish. However, only three of those species are currently described: the carabid beetle Coarazuphium cessaima (Gnaspini, Vanin & Godoy, 1998); the pholcid spider Metagonia diamantina (Machado, Ferreira & Brescovit, 2011); and the catfish Rhamdiopsis krugi (Bockmann & Castro, 2010). Figure 8. Iansaoniscus paulae sp. nov. habitat A limestone bordering the Paraguacu river, where the Lapa do Bode cave's entrance is located B one of the entrances of Lapa do Bode cave C a secondary entrance of Lapa do Bode cave D adult specimen inside the cave.