Typhlarmadillidium occidentale Taiti & Montesanto 2018, n. sp.
Creators: name: Taiti, Stefano
name: Montesanto, Giuseppe
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Isopoda
Armadillidiidae
Typhlarmadillidium
Typhlarmadillidium occidentale

description: Typhlarmadillidium occidentale n. sp.
(Figs 9-11, 21D)
urn:lsid:zoobank.org:act: 78E1A6C8-9D88-483F-87C1-F33FD25FA02E
TYPE MATERIAL. — Holotype. ♂ Monte Pisano, Grotta del Cane di Uliveto, 137 T/PI, 43°42’09”N, 10°31’14”E, Caprona, Uliveto Terme, Prov. Pisa, leg. S. Taiti, G. A. Gruber and P. Maestrini, 3.II.2007 (MZUF 9670). Paratypes. 1 ♂, 7 ♀, same data as holotype (MZUF 9670); 5 ♂, 3♀, Monte Pisano, Buca della Croce di Agnano N. 2, 78 T/PI, 43°44’09”N, 10°28’25”E, Agnano, Prov. Pisa, leg. S. Taiti, 12.X.2011 (MZUF 9671); 2 ♂, 10 ♀, same locality, leg. S. Taiti and F. Stoch, 10.IX.2011 (MZUF 9672); 2 ♀, same data (MNHN-IU- 2017-1438); 1 ♀, Monti d’Oltreserchio, Grotta della Spoletta, 1431 T/PI, 43°47’44”N, 10°23’35”E, Vecchiano, Prov. Pisa, leg. S. Taiti, 25.I.2008 (MZUF 9673).
DIAGNOSIS. — A blind, colourless species of Typhlarmadillidium characterized by the pereonite 1 with postero-lateral corner slightly sinuous, telson with broadly rounded apex, uropod exopod shorter than telson, male pleopod 1 endopod with triangular apical part bent outwards and exopod with sinuous outer margin.
ETYMOLOGY. — Latin: occidentalis = western. The name refers to the most western distribution of the species within the genus.
DESCRIPTION
Maximum length: ♂, 8.5 mm; ♀, 9.5 mm. Body colourless, strongly convex, able to roll up into a perfect ball (Fig. 9A). Back smooth with sparse small triangular scale-setae (Fig. 9B); one line of noduli laterales per side on pereonites, more or less at the same distance from the lateral margin (Fig. 9A). Cephalon (Fig. 9C, D) with a V-shaped scutellum clearly opened dorsally and depressed, antennary lobes small, eyes absent. Pereonite 1 (Fig. 9E, F) with posterior margin slightly concave, postero-lateral corner slightly sinuous with no schisma, small rounded tooth on ventral surface. Pereonite 2 (Fig. 9G) and 3 with a small ventral rounded tooth. Telson (Fig. 9H) subtriangular, longer than wide, with broadly rounded apex. Antennula (Fig. 9I) of three articles, second article much shorter than first and third, third article with pointed apex and subapical row of seven aestethacs. Antenna (Fig. 9J) with fifth article of peduncle slightly longer than flagellum, second flagellar article about three times as long as first, five rows of 1-3 aesthetascs each on second article. Mandibles (Fig. 10A, B) with molar penicil semidichotomized, 2 + 3 free penicils on the left and 1 + 3 on the right mandible. Maxillula (Fig. 10C) outer branch with 4+ 6 (4 cleft) teeth, inner branch with two penicils. Maxilla (Fig. 10D) with bilobed and setose apex, outer lobe twice as wide as inner lobe. Maxilliped (Fig. 10E) endite with two triangular terminal spines, one subterminal strong seta and bilobed distal-medial corner. Pleopods 1 and 2 (Fig. 11D, E) with monospiracular covered lungs. Uropod (Fig. 10F) protopod slightly longer than exopod, exopod twice as long as wide, endopod much longer than exopod.
Male
Pereopod 1 (Fig. 11A) carpus with row of strong setae on sternal margin. Pereopod 7 (Fig. 11B) with no distinct sexual modifications, ischium with straight sternal margin. Genital papilla as in Fig. 11C. Pleopod 1 (Fig. 11D) exopod wider than long with sinuous outer margin and broadly rounded apex; endopod with triangular apical part slightly bent outwards bearing row of short setae. Pleopod 2 (Fig. 11E) exopod slightly shorter than endopod. Pleopod 3-5 exopods as in Fig. 11 F-H.
REMARKS
The new species is included in the genus Typhlarmadillidium since it has a V-shaped scutellum clearly opened dorsally, small antennary lobes, pereonite 1 with no schisma, telson triangular, and uropod much longer than wide.
To date, the genus Typhlarmadillidium included three species: T. kratochvili (Frankenberger, 1938) from Croatia, T. trebinjanum (Verhoeff, 1900) from Croatia, Herzegovina and Montenegro, and T. ruffoi Ferrara & Taiti, 1996 from north-eastern Italy. The new species considerably enlarges the genus distribution towards the West. The new species is readily distinguished from T. kratochvili and T. trebinjanum in the uropodal exopods not surpassing the apex of telson and in the shape of the telson with a broader distal part; from T. trebinjanum also in the male pereopod 7 ischium with straight instead of concave sternal margin (compare Fig. 11B and Strouhal 1939: fig. 12); from T. ruffoi in the telson being longer than wide, the uropodal exopod being comparatively longer, the male pleopod 1 exopod with sinuous outer margin and endopod with apical part pointed and bent outwards instead of rounded (compare Ferrara & Taiti 1996).
description: Published as part of Taiti, Stefano & Montesanto, Giuseppe, 2018, New species of subterranean and endogean terrestrial isopods (Crustacea, Oniscidea) from Tuscany (central Italy), pp. 197-226 in Zoosystema 40 (11) on page 208, DOI: 10.5252/zoosystema2018v40a11, http://zenodo.org/record/3741502