Sphaeromopsis persikolpos, Khalaji-Pirbalouty, Valiallah & Wägele, Johann-Wolfgang, 2009

Khalaji-Pirbalouty, Valiallah & Wägele, Johann-Wolfgang, 2009, Two new species of Sphaeromopsis (Crustacea: Isopoda: Sphaeromatidae) from the Persian Gulf, Zootaxa 2305, pp. 33-50 : 42-49

publication ID	https://doi.org/ 10.5281/zenodo.275370
DOI	https://doi.org/10.5281/zenodo.5214438
persistent identifier	https://treatment.plazi.org/id/D32CA737-FFFC-5518-88EA-D8E5FB28CCBD
treatment provided by	Plazi
scientific name	Sphaeromopsis persikolpos
status	sp. nov.

Treatment

Sphaeromopsis persikolpos View in CoL sp. nov.

( Figs 7–11 View FIGURE 7 View FIGURE 8 View FIGURE 9 View FIGURE 10 View FIGURE 11 )

Material examined. All material from the Iranian shores of the Persian Gulf.

Holotype: male (3.1 mm), Kish Island, Harrireh, in filamentous algal turf mats on shore rocks, 0 5 December 2007, 26°34’082” N, 53°58’296” E, coll. Reza Khalaji (ZMH-42320).

Paratypes: 6 adult males (up to 3.2 mm); 5 non-ovigerous females (up to 2.4 mm), same data as holotype (ZMH-42321); Kish Island, Forest Park, in the tide pools, 26 Jun 2006, 26°30’473” N, 54°02’680”: 6 adult males (up to 3.3mm), coll. V. Khalaji (ZMH-42322); Qushm Island, Ramchah, in the tide pools, 0 8 December 2007, 26°51’234” N, 56°08’462” E: 9 adult males (up to 3.2mm); 5 subadult (2.8 mm); 5 juveniles (up to 1.8 mm); 4 non-ovigerous females (up to 2.6 mm), V. Khalaji & A. Bahpouri (ZMH-42323); Qeshm Island, Shibderaz, 0 8 December 2007, 26°41’177”N, 55°56’051” E, sandy beaches, low algal turfs: 5 adult males (up to 2.9 mm); 2 non-ovigerous females (up to 2.3mm); 2 juveniles (1.8 mm), coll. V. Khalaji (ZMH-42324); Qeshm Island, Sea Cinema, 0 8 December 2007, 26°56’136” N, 56°58’296” E, in the tide pools: 6 adult males (up to 3mm); 5 subadult (up to 2.4mm); 5 juveniles (up to 1.4mm); 4 non-ovigerous females (up to 1.8mm), coll. V. Khalaji (ZMH-42325). Ziarat village, 0 4 December 2007, 27°05’403” N, 53°05’082” E, sandy beaches: 2 females (up to 2.5 mm); 2 adult males (3 and 3.5mm); 1 juvenile (1.6 mm), coll. V. Khalaji (ZMH- 42326).

Diagnosis. Head with a small rostrum point, not visible in dorsal view; antennule basal article robust; pereonites 2–7 without coxal sutures; pleon with posterior margin bearing single suture at either side; pleotelson elongated, nearly triangular, with a narrow pleotelson apex; areas of coxal plates 6 and 7 broad, extending backwards and overlapping the most lateral part of the following segment; exopod of uropod extending well beyond pleotelsonic apex, tapering to narrow apex.

Description of male. Body twice as long as greatest width; head smooth, rostral process weakly developed. Pereonites 1–7 smooth; pereonite 1 with widest coxal area; pereonites 2–7 without coxal sutures; coxal areas 2–4 triangular; coxal area 4 with more acute angle, 6 broad, extending backwards and overlapping the most part of the one behind; 7 shorter than 6, wide, lobate, extending backwards and overlapping laterally part of pleon; pleon posterior margin bearing single suture on either side. Pleotelson wider than long, with a clear dorsal dome, some foraminate scattered setae over surface ( Figs. 6 View FIGURE 6. A – B D, 6E); posterior margin produced to narrow apex, bearing some short fine setae, lateral margins folded ventrally.

Antennule basal article subequal in length to articles 2 and 3 together, article 3 about 1.4 as long as article 2, with 2 small sensory palmate setae on ventro-distal corner; flagellum 12–articled, extending to posterior of pereonite 2, articles 2–9 each bearing a single aesthetasc. Antenna peduncle article 5 longer than others; flagellum extending slightly beyond pereonite 3, with 12 setose articles.

Epistome visible dorsally, about 2 times as long as labrum, with rounded apex and concave lateral margins, some foraminate setae scattered over surface; arms with scale setae, extending beyond mid-length of labrum.

Maxillule lateral lobe mesial margin with a few simple setae, outer margin fringed with simple short setae, apical margin with 9 robust setae, some inferiorly serrate, mesial lobe with 4 comb and 1 simple setae, lateral margin with about 4 simple setae. Maxilla lateral and middle lobes with 4 curved robust nodular serrate setae; mesial lobe with 4 serrate robust and 3 stout comb setae, mesial margin with many short simple setae, proximal margin with 2 long and a few short simple sate. Right mandible incisor with 3 cusps, lacinia mobilis with 4 cusps; spine row with 3 serrate and 3 simple spines; molar process round; palp articles 1 about 0.8 as long as article 2, article 2 distolateral margin with 5 biserrate setae becoming progressively longer distally; article 3 with 8 biserrate setae, terminal seta being longest, outer margin with several simple fine setae. Maxilliped endite lateral margin weakly sinuate, distal margin with 4 stout blunt setae, set in amongst 6 distal circumplumose robust setae, mesial margin with 1 coupling hook and fringed with fine setae, many fine short and several scale setae over surface; palp articles 3–5 with 7, 4 and 6 setae respectively.

Pereopod 1 robust, basis about 2.5 times as long as greatest width, superior margin with short acute setae and 1 small sensory palmate seta, inferodistal angle with single long simple setae; ischium about 2.7 times as long as greatest width, inferior margin with several simple, many short setae and several toothed scales, superior margin with 3 long distally biserrate setae; on merus, carpus and propodus inferior margin fringed with short setae; merus 0.45 times as long as ischium, supero-distal angle with 3–4 long distally biserrate setae, some long setae and several toothed scales; carpus about 0.6 as long as wide, subtriangular, inferodistal angle with single biserrate robust seta; propodus 2.6 times as long as wide, inferior margin with some long setae and 2 biserrate robust setae, superodistal corner with 2 long simple setae; dactylus inferior margin with cuticular scales, secondary unguis curved, with 3 simple setae at base, superior margin with 2 short seta, distal margin with 2 simple sub-marginal setae.

Pereopod 2 basis about 4.5 times as long as wide, superior margin with many short acute setae and 2 small sensory palmate setae; ischium about 3.4times as long as greatest width, inferior margin with several short setae, superior margin with 3 long distally biserrate setae and 2 simple seta; on merus, carpus and propodus inferior margin fringed with short setae; merus about 0.5 times as long as ischium, superodistal angle with 3 long distally biserrate setae, 3–4 long setae and several toothed scales; carpus about 3 times as long as greatest width, inferior margin with some long setae and several toothed scales, superodistal angle with single small sensory palmate seta; propodus about 0.7 times as long as ischium, supero-distal corner with single simple and single small sensory palmate seta; dactylus inferior margin with cuticular scales, secondary unguis curved, with 3 simple setae at base, superior margin with single short seta, distal margin with 2 simple submarginal setae. Pereopod 3 similar to pereopod 2 as illustrated. Pereopod 4 basis about 2.8 times as long as wide, dorsally with many short acute setae and 2 small sensory palmate setae; ischium about 2.5 times as long as greatest width, superior margin with 4 long distally biserrate and some simple setae; merus about 0.5 times as long as ischium, superodistal angle with 5 long distally biserrate setae, inferior margin with 4–5 long setae and several toothed scales; carpus about 1.7 times as long as greatest width, supero-distal angle with single small sensory palmate seta; propodus about 0.8 times as long as ischium. Pereopod 5 similar to pereopod 4 as illustrated. Pereopod 6 basis about 3.3 times as long as greatest width, dorsally many acute setae and 1 small sensory palmate seta, medial surface with 2 widely spaced small sensory palmate setae and many short acute setae; ischium about 2.4 times as long as greatest width, inferior margin with several short setae, superior margin with 4 long distally biserrate and several short acute setae; on merus, carpus and propodus inferior margin fringed with short setae; merus about 0.5 times as long as ischium, superodistal angle with 5 long distally biserrate setae; carpus subequal in length to merus, inferodistal angle with single biserrate robust seta, superodistal angle with 1 biserrate robust and 1 sensory palmate seta; propodus about 0.7 times as long as ischium, superodistal corner with single sensory palmate, single long and 2 simple short setae; dactylus inferior margin with cuticular scales, secondary unguis curved, with 3 simple setae at base, superior margin with 3 short setae, distal margin with 2 simple sub-marginal setae.

Pereopod 7 similar to pereopod 6, however, basis medial surface with 4 widely spaced small sensory palmate setae; ischium about 2.8 times as long as greatest width; carpus proximal margin with 6 biserrate robust setae.

Penes elongated rami slender, tapering to narrowly rounded apices, length more than 7 times basal width, and lateral margins with proximally directed hand-like scales on distal third ( Fig. 6 View FIGURE 6. A – B F).

Pleopod 1 exopod and endopod with 21 and 11 plumose marginal setae respectively, endopod narrower and shorter than exopod, lateral margin concave, mesial margin with short setae; exopod proximal lateral corner with single stiff seta; sympodite mesial margin with 3 coupling hooks and some toothed scales. Pleopod 2 exopod and endopod equal in length, with 23 and 15 plumose marginal setae respectively; appendix masculina arising sub-basally, stout, sub-crescentic with medial convex margin, extending somewhat beyond endopod apex; sympodite with 3 distomesial coupling hooks and single distolateral stiff seta. Pleopod 3 exopod and endopod with 22 and 14 plumose marginal setae respectively; sympodite with 3 disto-mesial coupling hooks, lateral margin with fringe of thin setae and single seta on distolateral corner; endopod mesial margin straight with fringe of thin setae. Pleopod 4 both rami subequal in length, endopod narrower than exopod, mesial margins with some fine simple setae. Pleopod 5 exopod with 3 scale patches (2 distally of and 1 under the transverse suture), mesial margin with several fine simple and several acute submarginal setae.

Uropodal exopod extending well beyond pleotelsonic apex, tapering to narrowly rounded apex, lateral and medial margins with short simple setae and tricorn marginal setae; endopod mesial margin with simple marginal setae, distal margin sub-truncate and slightly serrate, lateral margin with simple and tricorn marginal setae.

Female. Differs from male in sexual characters, uropod rami and pleotelson: The uropod rami are smaller than in male, exopod subequal or smaller than endopod ( Fig. 10 View FIGURE 10 D); pleotelson elongation less than in male.

Etymology. The specific name is derived from “ Persia ”, the ancient Iranian empire, combined with “kolpos”, Gulf, and refers to the type locality (Persian Gulf).

Remarks. Among the Indian Ocean Sphaeromopsis species, the new species is most similar to S. reticulata Stebbing, 1910 , which was described from the Red Sea (Gulf of Aqaba). According to the drawings and comments given by Stebbing (1910) and Holdich & Harrison (1981), in S. reticulata the posterior margin of the pleon has two separate sutures on either side, but in S. persikolpos sp. nov., there is only a one such suture ( Fig. 6 View FIGURE 6. A – B D). The lateral margin of the uropodal exopod is crenulated in S. reticulate , but nearly smooth in S. persikolpos and the exopod in this species is longer with a narrow apex ( Figs. 9 View FIGURE 9 E, 13C). The new species also differs from S. reticulata for its sub-basally arising appendix masculina, the shape and setation of pereopods 1–7, pleopods 1–5, and the shape of the coxal areas of pereonites 6–7. Sphaeromopsis sei Storey, 2002 known from the Andaman Sea ( Thailand), is the only species in the genus with a narrow pleotelson apex. However, based on the description of this species given by Storey (2002) and based on examination of its paratypes (ZMUC CRU3264, Nai Harn Beach, Thailand), S. sei can readily be distinguished from S. persikolpos by its longer epistome, a pleon with two sutures along the posterior margin, shorter uropodal exopod with serrated lateral margins, the shape of the shorter penes, the dense tuft of short setae on the inferior margins of the merus, carpus and propodus, and the longer setae along the superior margins of the pereopods. Moreover, the peduncle article 4 of the antenna has 2 long slender setae in S. sei .