Porcellio mehrdadi, Kashani & Ahdiyeh & Zahra, 2017

Kashani, Ghasem M., Ahdiyeh, Abedini & Zahra, Hatami, 2017, Terrestrial isopods of the genus Porcellio Latreille, 1804 (Isopoda; Oniscidea) in Iran, with a description of a new species, Zootaxa 4311 (1), pp. 129-136 : 134-136

Porcellio mehrdadi sp. nov.

Material examined. Holotype: male, 20 mm, Lordegan , 5 km to Atashgah fall, by the Khersan River, under the bark of a rotten tree, 21°16.4'N, 50°58.3'E, elev. 1460 m, 15 July 2015, leg. G.M. Kashani, A. Abedini & Z. Hatami ( ZUTC 6498 ).

Paratypes. same data as holotype, one male and two females ( ZUTC 6499 ) ; same data as holotype, one male and one female ( IRIPP Iso-1065) ; same data as holotype, one male and four females ( PCGMK 2164 ) ; [1] Sarkhoon , 31°44.9'N, 50°32.8'E, 18 June 2016, leg. the authors, six males and eleven females ( PCGMK 2323 ) ; [2] Sarkhoon to Lordegan, 31°40.3'N, 50°44.4'E, 18 June 2016, leg. the authors, one male and one female ( PCGMK 2325 ) ; [4] Lordegan to Atashgah fall, 31°20.0'N, 50°54.7'E, 19 June 2016, leg. the authors, three males and two females ( PCGMK 2333 ) ; [5] Lordegan to Atashgah fall, by the Khersan river, 31°16.8'N, 50°58.0'E, 19 June 2016, leg. the authors, two males and three females ( PCGMK 2336 ) ; [6] Lordegan to Atashgah fall, by the Khersan river, 31°16.0'N, 50°58.4'E, 19 June 2016,leg. the authors, seven males and two females ( PCGMK 2340 ) ; [3] Monj , 31°32.4'N, 50°58.0'E, 19 June 2016,leg. the authors, one male and one female ( PCGMK 2343 ) ; [7] Dehdasht, Pirzal, 1 may 2002, leg. M. Rezaei, two males and twelve females (PCGMK 1273).

Diagnosis. Cephalon with well developed quadrangular lateral lobes; male uropod exopodites elongated and pereopod VII ischium with setose areas on rostral surface and ventral margin.

Description. Body flattened; length up to 20 mm in both males and females. Color pale brown to dark gray with usual muscles spots ( Fig 2A –C). Head with well developed quadrangular lateral lobes; median lobe with incision in middle; vertex granulated with several pointed tubercles ( Fig. 3 A). Antenna long and slender, surpassing posterior margin of pereon-tergite II; fifth article of peduncle longer than flagellum, with length: width ratio 10:1; flagellum with two articles, proximal one three times as long as distal one ( Fig. 3 B).

Pereon granulated with conspicuous pointed tubercles. Pereonite I with concave posterolateral margin ( Fig. 3 A).

Pereopod I ischium triangular, carpus with depression on rostral surface equipped with slender scales ( Fig. 3 D).

Pleon with continuous outline with pereon, granulated with tubercles ( Fig. 3 E). Telson triangular, with concave sides and acute apex, not surpassing uropod-protopodites. Uropod exopodites as long as telson in females, up to three times as long as telson in males ( Fig. 3 C). Pleopod exopodites I–II with monospiracular internal lungs ( Fig. 4 B–C).

Male: Pereopods I–II merus and carpus with brushes of setae. Pereopod VII ischium with concave ventral margin equipped with hairy brush of small setae, rostral surface with setose area ( Fig. 3 E). Pleopod endopodite I straight, apex with line of short setae ( Fig. 4 A); exopodite I with short rounded hind lobe, outer margin with row of small setae ( Fig. 4 B). Pleopod endopodite II as long as exopodite; exopodite triangular with line of seta on outer margin ( Fig. 4 C). Pleopod exopodites III–IV with concave outer margins ( Fig. 4 D–E) bearing line of small setae. Pleopod exopodite V triangular with line of seta on outer margin ( Fig. 4 F).

Remarks. Porcellio mehrdadi sp. nov. is characterized by the well developed quadrangular lateral lobes of the head; male pereopod VII ischium with the setose areas on rostral surface and ventral margin, and elongated uropod exopodites.

Schmalfuss (1992) revised the western Asian species of Porcellio in which P. evansi and P. obsoletus were reported from Iran. Geographically, the new species is distributed within the distributional range of P. evansi and it was found even syntopically with the latter species in one locality. The two species, however, differ in their coloration, in the shape of the head and telson and in possessing the setose areas on pereopod VII ischium.

Etymology. The species is named after Mehrdad Rezaei who collected the species for the first time.

Distribution. Southwestern Iran.

Figures

FIGURE 2. A, living specimens of Porcellio mehrdadi sp. nov. from the type locality; B, holotype; C, a female paratype.

FIGURE 3. Porcellio mehrdadi sp. nov., male, paratype. A, head and first pereonite; B, antenna; C, telson and uropods; D, pereopod I; E, pereopod VII; F, pereopod VII ischium, frontal view; G, pereopod VII ischium, caudal view. Scales = 1 mm.

FIGURE 4. Porcellio mehrdadi sp. nov., male, paratype. A, pleopod endopodite I; B, pleopod exopodite I; C, pleopod II; D, pleopod exopodite III; E, pleopod exopodite IV; F, pleopod exopodite V. Scales = 0.5 mm.