Xangoniscus jonasi Lopez-Orozco, Bichuette & Campos-Filho 2024, sp. nov.
Creators: name: López-Orozco, Carlos Mario
name: Borja-Arrieta, Ricardo
name: Carpio-Díaz, Yesenia Margarita
name: Gallão, Jonas Eduardo
name: Campos-Filho, Ivanklin Soares
name: Bichuette, Maria Elina
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Isopoda
Styloniscidae
Xangoniscus
Xangoniscus jonasi

description: Xangoniscus jonasi López-Orozco, Bichuette & Campos-Filho sp. nov.
Figs 1, 7, 8, 9, 10
Type material.
Holotype • 1 male (parts in slides) (LES 0030097), Bahia, Carinhanha, Gruna da Serra Solta cave, - 13.510573, - 43.75207, 24 October 2023, leg. JE Gallão.
Description.
Maximum body length: male 6.5 mm. Body outline as in Figs 7 A, B, 8 A. Colourless (Fig. 7). Dorsal surface smooth, with scattered fringed scale setae (Figs 7 A – E, 8 B). Cephalon (Figs 7 C, D, 8 C) with large quadrangular antennary lobes; vertex with slightly lateral depression to fit antennae when extended backwards, profrons with V-shaped suprantennal line, not surpassing antennule insertion; eyes absent. Pereonite 1 epimera with distal corners not developed frontwards, posterior corners right-angled; pereonites 2–7 epimera gradually directed backwards, posterior corners progressively more acute; pleon narrower than pereon; pleonites 3–5 epimera posterior point not developed (Figs 7 A, B, D, 8 A). Telson with concave sides and rounded apex (Fig. 8 D). Antennula (Fig. 8 E) composed of three articles, proximal and distal articles subequal in length, second article short, distal article with eight very long aesthetascs. Antenna (Fig. 8 F) short, not surpassing pereonite 3 when extended backwards; flagellum of equal length of fifth article of peduncle, composed of three articles subequal in length. Left mandible (Fig. 8 G) with two penicils; right mandible (Fig. 8 H) with lacinia mobilis and one penicil. Maxillula (Fig. 8 I) inner endite with three penicils; outer endite with 5 + 5 teeth, apically simple, and two plumose stalks. Maxilla (Fig. 8 J) with setose and bilobate apex, outer lobe smaller. Maxilliped (Fig. 8 K) basis enlarged on distal portion bearing fringe of fine setae; first article of palp with two tiny setae, distal articles with three tufts of setae; endite rectangular, outer and medial margins setose, apically with two triangular teeth and large rounded penicil. Uropod (Fig. 8 D) branches short, endopod inserted proximally, exopod and endopod equal in length. Pereopods 1–7 (Fig. 9 A – G) gradually elongated, with merus, carpus, and propodus bearing sparse setae; dactylus of one claw bearing many setae on inner and outer margins.
Male. Pereopod 1 (Fig. 9 A) carpus with large antennal grooming brush. Pereopod 2–4 (Fig. 9 B – D) merus with scales on sternal margin. Pereopods 5 and 7 (Fig. 9 E, G) without distinct modifications. Pereopod 6 (Fig. 9 F) carpus slightly grooved on sternal margin, propodus slightly enlarged on median portion. Genital papilla (Fig. 10 B) lanceolate. Pleopod 1 (Fig. 10 A) exopod trapezoidal, longer than wide, distal margin slightly convex, inner and outer margins bearing fringe of fine setae; endopod longer than exopod, with narrow basal article and flagelliform distal article; basipod distal margin elongate, longer than exopod, with semicircular apex, with fine and long setae. Pleopod 2 (Fig. 10 C) exopod trapezoidal, distal margin slightly convex bearing three setae; endopod of two articles, distal article about three times as long as proximal, with distal margin subquadrangular and apex rounded, with transversal process in V-like on apex in ventral view. Pleopod 3 (Fig. 10 D) exopod triangular, longer than wide, covering pleopods 1 and 2, fringed with short setae. Pleopod 4 and 5 (Fig. 10 E, F) exopods trapezoidal, wider than long, with margins bearing several short setae.
Etymology.
The new species is named after Jonas Kahnwald, the protagonist of the “ Dark ” series, who explores caves to travel through time and space. The epithet “ jonasi ” is a tribute to the isolation and sense of separation from time and space that caves represent, evoking the central theme of “ Dark ”. The species reflects extreme adaptation to dark depths, just as Jonas adapts to the complexities and paradoxes of time.
Distribution.
Presently known only from Gruna da Serra Solta cave in the Serra do Ramalho karst area, state of Bahia, northeastern Brazil (Fig. 1).
Remarks.
Xangoniscus jonasi sp. nov. differs from all other species of the genus in having the antennula with eight long aesthetascs (vs. two in X. aganju, X. lapaensis, and X. odara, three in X. ibiracatuensis, X. lundi and X. santinhoi, four in X. dagua, four or five in X. ceci, five in X. loboi, six in X. itacarambiensis, twelve in X. chaimowiczi sp. nov.), pleopod 1 basipod distal margin semicircular apex, longer than exopod (vs. simples and shorter than exopod in X. lundi, X. dagua, X. ceci, X. ibiracatuensis, X. itacarambiensis, X. loboi, X. odara, X. santinhoi, acute and longer than exopod in X. chaimowiczi sp. nov., X. lapaensis and X. aganju).
Natural history.
The species showed low abundance (only one individual caught along the cave). The only individual of X. jonasi sp. nov. captured was found in the aphotic zone on a very wet, muddy substrate, under the cracks formed by the stream current, just a few meters from a pond (Fig. 1 C).
description: Published as part of López-Orozco, Carlos Mario, Borja-Arrieta, Ricardo, Carpio-Díaz, Yesenia Margarita, Gallão, Jonas Eduardo, Campos-Filho, Ivanklin Soares & Bichuette, Maria Elina, 2024, Describing to preserve – three new species of Xangoniscus (Oniscidea, Styloniscidae) of unprotected caves in dry areas from Bahia state, northeastern Brazil, pp. 79-104 in Subterranean Biology 50 on pages 79-104, DOI: 10.3897/subtbiol.50.139914