Albosciajotajota Campos-Filho, Bichuette & Taiti sp. nov.

urn:lsid:zoobank.org:act: 872601F5-076C-44FD-83E7-0FC35123E54D

Figs 2–4, 14

Diagnosis

Eyes reduced to rudimentary ommatidia, distal article of antennula with six lateral aesthetascs plus apical pair and male pleopod 1 endopod slightly longer than exopod, with short and thickset distal portion.

Etymology

This new species is named after Joaquim Justino dos Santos (in memoriam), also known as ʻJota Jotaʼ, who discovered several caves in the Alto Ribeira karst area and was a fantastic guide at PETAR.

Material examined

Holotype BRAZIL – São Paulo State, Iporanga • ♂; PEI, Gruta Minotauro; 24°16′34″ S, 48°27′22″ W; 26–30 Mar. 2009, F. Pellegatti-Franco leg.; parts in micropreparations; LES 647.

Paratypes BRAZIL – São Paulo State, Iporanga • 2 ♀♀; PETAR, Ressurgência das Areias de Água Quente Cave; 24°33′45″ S, 48°40′18″ W; 29 Sep. 2012; M.E. Bichuette leg.; LES 18852.

Description

MEASUREMENTS. Maximum body length: male 4 mm, female 4.5 mm.

BODY. Body pigments absent. Body (Fig. 2A) slender with lateral sides almost parallel; dorsal surface smooth, bearing short, triangular scale-setae (Fig. 2B). Noduli laterales very long (Fig. 2C); d/c and b/c coordinates as in Fig. 2 D–E.

CEPHALON. Lateral lobes not developed, frontal line absent, suprantennal line slightly bent downwards in middle; eyes reduced, with rudimentary ommatidia (Fig. 2F).

PEREON. Pereonite 1 epimera with anterior corners slightly directed upwards, not surpassing median portion of cephalon, epimera 2–7 gradually directed backwards (Fig. 2A).

PLEON. Narrower than pereon; pleonites 3–5 epimera short, adpressedwith small posterior points directed backwards, bearing some glandular pores; telson triangular with lateral margins straight, rounded apex (Fig. 2G).

ANTENNULA. Composed of three articles, distal article bearing six lateral aesthetascs in three sets plus apical pair (Fig. 2H).

ANTENNA. Very long, reaching fourth pereonite when extended backwards; flagellum of three articles, distal article longest; apical organ short, bearing two long free sensilla (Fig. 2I).

MOUTH. Mandibles bearing dense cushion of setae on incisor process, molar penicil consisting of several branches; right mandible (Fig. 3A) with 1+1 penicils, left mandible (Fig. 3B) with 2+1 penicils. Maxillula (Fig. 3C) inner endite with distal margin rounded and bearing two penicils; outer endite with four simple teeth plus accessory tooth on outer set, inner set of five pectinate teeth plus one vestigial tooth on rostral surface. Maxilla (Fig. 3D) inner lobe rounded, covered with thick and thin setae; outer lobe slightly wider than inner lobe, covered with thin setae. Maxilliped (Fig. 3E) palp with two strong setae on proximal article; endite subrectangular, medial seta strong, surpassing distal margin, distal margin with two hook-like setae, rostral surface with setose sulcus ending in one strong, triangular seta.

PEREOPODS. Pereopods 1–7 merus to propodus bearing sparse, long setae on sternal margin; pereopod 1 carpus with transverse antennal grooming brush; dactylus of two claws, inner claw not surpassing outer claw, dactylar and ungual setae simple, not surpassing outer claw.

UROPOD. Protopod subquadrangular with endopod and exopod inserted at same level; protopod and exopod outer margins grooved, bearing glandular pores; exopod slightly longer than endopod (Fig. 4A).

PLEOPOD EXOPODS. Without respiratory structures (Fig. 4E–I).

Male

PEREOPODS 1 AND 7. Without any sexual dimorphism (Fig. 4B–C).

GENITAL PAPILLA. Stout, with triangular ventral shield, papilla slightly longer than ventral shield, bearing two apical orifices (Fig. 4D).

PLEOPODS. Pleopod 1 (Fig. 4E) exopod subcircular, wider than long; endopod short and stout, with distal portion thickset and slightly bent outwards, rounded apex. Pleopod 2 (Fig. 4F) exopod triangular, outer margin almost straight, bearing one seta, distal margin rounded; endopod longer than exopod. Exopods of pleopod 3 and 4 subrectangular, outer margin almost straight and bearing three long setae (Fig. 4 GH). Pleopod 5 exopod (Fig. 4I) triangular, outer margin convex, bearing three long setae, distal margin rounded.

Remarks

To date, the genus Alboscia comprises four species: A. elongata Schultz, 1995 from Paraguay; A. itaipuensis Araujo & Quadros, 2005, A. ornata Araujo, 1999 and A. silveirensis Araujo, 1999 from Brazil (Schultz 1995; Araujo 1999; Araujo & Quadros 2005). The genus is mainly defined by the slender habitus with lateral sides almost parallel, presence of conspicuous noduli laterales, epimera of pleonites closely appressed to pleon, maxillula outer endite with pectinate teeth on outer set and pleopod exopods without respiratory structures (Araujo 1999). The presence of pectinate teeth on the outer endite of the maxillula is present in other lineages of Oniscidea, e.g., Ligia Fabricius, 1798 ( Ligiidae Leach, 1814), Armadilloniscus Uljanin, 1875 ( Detonidae Budde-Lund, 1906)), Benthana Budde-Lund, 1904, Benthanops Barnard, 1932 and Ctenoscia Verhoeff, 1928 (Philosciidae), and Rhyscotidae Budde-Lund, 1908 (see Taiti & Ferrara 1982; Leistikow 1997; Schmidt 2002, 2003; Campos-Filho et al. 2015a). This character state is considered to be plesiomorphic (Leistikow 2001; Schmidt 2002).

In the shape of the male pleopod 1 exopod, Alboscia jotajota sp. nov. resembles A. elongata and A. silveirensis . It differs from both species in having eyes with rudimentary ommatidia (vs three ommatidia in A. elongata; single ommatidium in A. silveirensis), antennula with six lateral aesthetascs arranged in three sets (vs five in one set in A. elongata; two in one set in A. silveirensis) and the male pleopod 1 endopod slightly longer than the exopod, with short and thickset distal portion (vs more than twice as long as exopod and distal portion slender in A. elongata; three times as long as exopod and distal portion slender in A. silveirensis).

The absence of body pigment and absent/reduced eyes are common to all species of Alboscia, which probably indicates an endogean way of life. However, Alboscia jotajota sp. nov. is considered to be troglobiotic since no specimen was collected during surveys outside the caves where this species occurs.