Protracheoniscus gakalicus Kashani, Malekhosseini & Sadeghi, 2013, n. sp.
Creators: name: Kashani, Ghasem M.
name: Malekhosseini, Mohammad-Javad
name: Sadeghi, Saber
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Isopoda
Trachelipodidae
Protracheoniscus
Protracheoniscus gakalicus

description: Protracheoniscus gakalicus n. sp.
Material examined. Holotype: male, 9 mm, East of Gachsaran, Gakal cave, 18 May 2012 (CBSU-Cr-Is.1001). Paratypes: one male, same data as for holotype (SMNS T615); one female, same data as for holotype (SMNS T616); one male, same data as for holotype (SMF 43366); four males and two females, same data as for holotype (PCGMK 1603); one male and two females, same data as for holotype (CBSU-Cr-Is.1002); three males and three females, same locality as for holotype, 2 October 2012 (CBSU-Cr-Is.1003)
Diagnosis. Body pigmentless. Cephalon with developed lateral lobes, eyes absent. Male pereiopod VII ischium stout with several strong setae on tergal margin. Male pleopod endopodite I straight, exopodite subrectangular.
Description. Maximum length: male and female 10 mm. Body elongated, pigmentless (Fig. 2). Eyes absent. Cephalon with well developed lateral and median lobes (Fig. 3 A), no supraantennal line.
Antenna long, reaching the posterior margin of fourth pereion tergite; fifth article of peduncle as long as flagellum; flagellum with two articles of the same size (Fig. 3 D).
Antennule of three articles with a tuft of long aesthetascs at apex (Fig. 3 E).
Mandible with molar penicil consisting of several plumose setae; 1+3 free penicils on the right mandible and 2+3 on the left (Fig. 4 A, B).
Maxillule with outer branch bearing 4+5 simple teeth (Fig. 4 C); inner branch with two long penicils and a triangular posterior point (Fig. 4 D).
Maxilla distally bilobate and setose, inner lobe wider than outer one, three aesthetascs between the two lobes (Fig. 4 E).
Maxilliped endite with two small triangular teeth on anterior margin (Fig. 4 F).
Pereion smooth; posterolateral margins of first pereionite convex (Fig. 3 A); noduli laterales on pereionites 1–4 distinctly more distant from the lateral margins than those on pereionite 5–7 (Fig. 3 C).
Pleon smooth, pleopod exopodites I–V with monospiracular covered lungs (Fig. 5 B–F).
Telson triangular, almost as long as wide, with slightly concave sides and acute apex, slightly surpassing uropod protopodites.
Uropod protopodites with conspicuous incision on lateral margins; exopodite long, twice as long as telson (Fig. 3 B).
Male: pereiopod I merus and carpus with brushes of trifid setae (Fig. 3 F).
Pereiopod VII ischium stout with straight sternal margin, several strong setae on tergal margin (Fig. 3 G).
Pleopod exopodite I somehow rectangular, with a row of fine setae on outer margin (Fig. 5 B); endopodite straight, with a line of small setae at apex (Fig. 5 A).
Pleopod endopodite II as long as exopodite; exopodite triangular with a row of fine setae on outer margin (Fig. 5 C).
Pleopod exopodites III–V as in Fig. 5 D–F.
Remarks. A species of Protracheoniscus characterized by the smooth body, rounded posterolateral margins of the first pereionite, the head bearing short or well-developed lateral lobes, the triangular telson and pleopodexopodites I–V with monospiracular covered lungs (Schmidt 2003). Diagnostic characters of this species including shape of antenna, cephalon, posterolateral margins of first pereionite and telson are well corresponding with the genus Protracheoniscus. The genus includes more than 60 valid species (see Schmalfuss 2003) distributed in Eurasia from Spain to Japan. This is the first known species of the genus adapted for a cavernicolous way of life, acquiring some unique traits that distinguish it readily from other species. Lack of pigmentation and eyes, and possessing long antenna and uropodal exopodites are among these adaptations.
Distribution. Southwest of Iran.
Etymology. The name of the species is after the type locality, Gakal cave.
description: Published as part of Kashani, Ghasem M., Malekhosseini, Mohammad-Javad & Sadeghi, Saber, 2013, First recorded cave-dwelling terrestrial isopods (Isopoda: Oniscidea) in Iran with a description of a new species, pp. 591-596 in Zootaxa 3734 (5) on pages 593-595, DOI: 10.11646/zootaxa.3734.5.8, http://zenodo.org/record/216982