Caraiboscia christiani, Leistikow, 2001

Leistikow, Andreas, 2001, A new species of Caraiboscia Vandel, 1968 from South America, and a type species for Colombophiloscia gen. n. (Crustacea: Oniscidea: Crinocheta), Journal of Natural History 35 (4), pp. 497-514 : 503-509

Caraiboscia christiani sp. n.

( Figures 4 ±8)

Material. One male (HOLOTYPE, body length 3.5 mm): Venezuela, PenõÂnsula de Paria, eastern part of south coast, 10 ss 35,94 ¾ N 63 ss 11,81 ¾ E, along brook with cocoa plantations and moist forest, upper part with water, concrete pond with moist bottom under wood, leg. 9 April 1998, C. Schmidt, ZMB uncatalogized; PARATYPES: 22 males, seven ovigerous females, ten females, ®ve immatures: same data as holotype; one male, one ovigerous female, one female: Venezuela, PenõÂnsula de Paria, Puy Puy, 10 ss 42.00N 62 ss 58.05W, bay with sandy beach, coconut palms, surrounded by dry mountains, behind shore line swampy area with reed, under trees in decaying leaves, leg. 29 March 1998, C. Schmidt; 19 males, 15 ovigerous females, 6 imm.: Venezuela, Peninsula de Paria, Puy Puy 10 ss 42.00 ¾ N 62 ss 58.05 ¾ W, bay with sandy beach, coconut palms, surrounded by dry mountains, banana plantation at the eastern part of the bay, in leaf litter, leg. 31 March 1998, C. Schmidt; one female: Venezuela: PenõÂnsula de Paria, El Refugio de la Cerbatana, primary forest with high trees covered with Bryophyta, Bromeliaceae , Lycopodiaceae , vines, very humid, in leaf litter, leg. 4 April 1998, C. Schmidt, all own collection.

Colour. Entirely pigmentless save the ommatidia bearing dark pigment.

Cephalothorax. Vertex covered with specialized tricorn-like setae, compound eyes reduced, four individualized ommatidia present, no linea frontalis and supra-antennalis, lamina frontalis laterally bordered by small grooves, lateral lobes small (®gure 4, Ctf).

Pereon. Dorsum covered by specialized, forwardly bent tricorn-like setae, caudal margin lacking tricorns, coxal plates with sulcus marginalis, scattered gland pores and nodulus lateralis, all inserted at the same distance from lateral margin (®gure 4, Cx3 / Cxp).

Pleon. Retracted from pereon, each pleonite with transverse row of tricorn-like setae, neopleurae attached, pleotelson with straight margins.

Appendages

Antennula. Three-articulate with medial article shortest, distal apex bearing medial fringe of diverging aesthetascs (®gure 4, An1).

Antenna. Densely covered with short tricorn-like setae, length ratio of peduncular articles 1:2:2:3:4, ¯agellum three-articulate, as long as distal peduncular article, apical organ as long as distal ¯agellar article, free sensilla short (®gure 4, An2).

Mandible. Molar penicil consisting of about eight branches, pars intermedia with two penicils on left, one on right side, additional penicil proximally (®gure 5, Mdl / r).

Maxillula. Medial endite with two slender penicils, lateral endite with 41 5 teeth apically, lateral fringe of trichiae stepped (®gure 5, Mx1).

Maxilla. Both lobes subequal in breadth, bearing scattered pectinate scales, medial lobe hook-shaped, with about seven cusps apically (®gure 5, Mx2).

Maxilliped. Sulcus lateralis present on basipodite, palp with two setal tufts, proximal one considerably stalked, seta of proximal article subequal in length, palp lacking setation save some characteristically arranged trichiae on rostral side, small knob-like penicil present (®gure 5, Mxp).

Pereopods. Rather stout, medial sensory spines prominent (®gure 6/7, PE1±7), especially distal one of carpus, antenna-groomin g brush on pereopod 1 propus and carpus, three ornamental sensory spines of carpus with double-fringed apex (®gure 6, Sc1), dactylus with slightly plumose dactylar seta, two interungual setae and long inner claw in pereopods 1 to 4 (®gure 6, Da1), one interungular seta and short inner claw in pereopods 5 to 7 (®gure 7, Da7).

Sexual dimorphism. Male pereopod 7 ischium with medio±distal groove, not present in female.

Pleopods. Pleopod exopodites rhomboid, bearing about four sensory spines laterally, medial margin with trichiae, no respiratory areas discernible, endopodites slightly bilobate (®gure 8, PL1±5).

Sexual dimorphism. Male pleopod 1 exopodite broad, falciform, endopodite straight, with caudal row of spines, apex bifurcate, lateral lobe rounded with some proximally directed hooks, medial lobe pointed, with spines continuing caudal row, caudally inserting hyaline lobe (®gure 8, PL1). Pleopod 2 exopodite pyriform with almost straight lateral margin bearing three sensory spines, endopodite slender, laterally on half-length with some lamellae (®gure 8, PL2).

Uropod. Endo- and exopodite short, exopodite inserting slightly distally of exopodite, protopodite grooved (®gure 7, UR).

Genital papilla. Short, ventral shield surpassed by truncate terminal spatula (®gure 8, Gen).

Etymology. The species is dedicated to my colleague Christian Schmidt who collected the material in Venezuela in 1998.

Remarks. This species was found abundantly in the lowlands of Venezuela. It is quite close to C. microphthalma from which it diOEers in several characters, the autapomorphies of the latter were listed above. Caraiboscia christiani is de®ned by the following autapomorphic characters: all teeth of the maxillula simple and the male pleopod 1 endopodite bearing a cleft apex with a small hyaline lobe.The latter character seems to be more derived than the pointed endopodite 1 of C. microphthalma , which is close to the ground pattern of the Oniscoidea, although the presence of a row of tubercles is an autapomorphy of this species. In C. christiani , the lateral lobe of the apex bears some proximally directed granulae. In both species, a caudomedial row of spines is present, a symplesiomorphy of the genus and most of the Oniscoidea.

With respect to the cephalothorax, there is another diOEerence between the two species: C. microphthalma has a linea frontalis, which is slightly modi®ed, namely the medial part is reduced. In C. christiani , this structure is totally lacking due to reduction.

Figures

FIG. 4. Caraiboscia christiani sp.n., male, holotype 3.5 mm. An1 antennula, with detail of distal article in lateral view; An2 antenna, with detail of apical organ; Ctf cephalothorax in frontal view; Cx3 coxal plate III; Cxp coxal plates with position of noduli laterales; Had habitus in dorsal view; Hal habitus in lateral view; Sx4 tricorn-like seta of coxal plate IV; Tel pleotelson.