Cymodoce delvarii sp. nov.

(Figs 16–19)

Material examined. All material from Iran, northern Persian Gulf.

Holotype. 3 (7.8 mm), Gloestan-e-Saheli, 28 April 2010, 28°14’198”N, 51°16’455”E, sub tidal, 1.5 m depth, on green algae, coll. A. Samimi and V. Khalaji (ZMH –K–42596).

Paratypes: 2 3 (7.5, 8.1 mm), 3 sub-adult 3 (5.5, 6.1, 7.5 mm), 9 ƤƤ (5.5–7.5 mm), same data as holotype (ZMH –K–42597). 1 3 (7.1 mm), 3 sub-adult 3 (5.5, 6.0, 6.5 mm), 5ƤƤ (5.5– 6.5 mm), Gloestan-e-Saheli, 28 April 2010, 28°14’198”N, 51°16’455”E, sub tidal, 1.5 m depth, on green algae, coll. A. Samimi and V. Khalaji (ZUTC Iso. 1100); 1 sub-adult 3 (4.9 mm), 2 ƤƤ (4.0, 5.0 mm), 5 juveniles (2.5–3.5 mm), Qeshm Island, northern coast, 0 7 December 2007, 26°27’272”N, 36°15’105”E, coll. V. Khalaji and A. Bahpouri (ZUTC Iso. 1101).

Diagnosis. Pleon and pleotelson strongly tuberculate, all apically setose. Pleotelson anterodorsal part with 2 prominent longitudinal ridges and 2 irregular longitudinal rows of prominent tubercles between them; bearing pair of prominent tubercles on lateral side of prominent bifid bosses; posterior part bearing large oval dome. Uropod rami not extending to level of pleotelsonic medial lobe apex; endopod with a prominent tubercle proximally. Appendix masculina apical part folded, extending slightly beyond endopod.

Description of male. Body about 2.2 times as long as greatest width. Head and pereonites 1–3 dorsal surfaces smooth; pereonites 1–7 posterior margins with 6 tufts of setae; pereonite 4–5 with a transverse row of weak tubercles; pereonites 6–7 with 2 rows of small prominent tubercles.

Pleon with transverse row of tubercles over two sutures at either side, dorsally bearing scattered dense tubercles, posterior margin with two extensions; posterolateral margins with a fringe of very long sub-marginal setae.

Pleotelson bearing scattered tubercles over surface, with 2 prominent longitudinal ridges, each dilating posteriorly into a prominent bifid boss; each boss flanked on either lateral side by 2 prominent tubercles, one posterior to other; dorso-medial surface bearing 2 irregular longitudinal rows of prominent tubercles between dorsal ridges; posterior half with medial, large oval dome; apex of pleotelson clearly trilobed; lateral lobes blunt; medial lobe extending just beyond lateral lobes apices, bearing tuft of long setae, dorsally tuberculate (Figs. 16 A, B; 20 A–C; 21C).

Antennule (Fig. 16 C) first peduncle article bearing scattered weak tubercles, all apically setose, with 4 sensory palmate sub-marginal setae on upper surface; article 2 with some small sensory palmate setae on ventral and dorsal margins, article 3 slender, 1.6 times as long as article 2; flagellum with 17 articles, articles 5–15 each bearing single aesthetasc.

Antenna (Fig. 16 D) peduncle article 1 setose; articles 2–5 each bearing long setae on posterior corner; article 5 about 1.15 times as long as article 4; flagellum with 19 articles.

Epistome (Fig. 16 E) granulate, with acute apex, antrolateral margin straight.

Left mandible (Fig. 17 C, D) lacinia mobilis with 3 cusps; spine row of 6 serrate or spines. Palp article 1 longer than 2 with a long simple seta distally, articles 2 and 3 distolateral margins with approximately 13 and 19 biserrate setae.

Maxillule (Fig. 17 A) lateral endite with long fine setae on mesial margin, outer margin bearing small setae, apical margin with 10 simple or serrate RS, 2 short RS and 1 serrated robust submarginal seta; mesial endite with 4 long, robust, comb setae and a short simple seta.

Maxilla (Fig. 17 B) lateral and middle endites each with 10 curved pectinate RS; mesial endite with 2 long sparsely plumose setae, 2 long robust comb setae, about 10 robust proximally plumose and distally biserrate setae, and some slender simple setae.

Maxilliped (Fig. 17 E) endite lateral margin sinuate, mesial margin with single coupling hook, distal margin with 3 blunt rarely plumose RS and about 7 long circumplumose RS, inner surface with 3 long circumplumose RS and a transverse raw of stout finely serrate setae.

Pereopod 1 (Fig. 17 F) basis about 2.7 times as long as greatest width; ischium superior margin with 1 RS on medial angle; merus superodistal angle with 3 RS, inferior margin with 5 robust biserrate setae and 1 long apically palmate seta; carpus inferior margin with 4 robust biserrate setae; propodus inferior margin with 5 robust biserrate setae set in amongst some acute scales.

Pereopod 2 (Fig. 17 G) ischium superior margin with 2 RS on medial angle; merus inferior margin with 3 robust biserrate setae and 1 long apically palmate seta; merus and carpus inferior margin fringed with short setae; propodus inferior margin with 5 robust biserrate setae set in amongst some acute scales.

Pereopod 3 (Fig. 18 A) is similar to pereopod 2.

Pereopods 4 and 5 (Fig. 18 B, C) are similar as illustrated.

Pereopod 6 (Fig. 18 D) basis about 3 times as long as greatest width, superior margin with several simple and 3 sensory palmate setae; ischium superior margin with 6 long and small RS distally; merus superior distal margin with 5 long setae, inferior margin with 7 robust biserrate setae with various sizes and a single long apically palmate seta; carpus subequal in length to merus, inferior margin 7 robust biserrate setae and 1 single long apically palmate seta, distal margin with 6 robust biserrate or simple setae; propodus superodistal corner with 4 slender and a single sensory palmate setae, inferior margin with 4 robust biserrate setae.

Pereopod 7 (Fig. 18 E) similar to 6 except in some details such as number of setae.

Penial processes (Fig. 19 F, 20E) about 9 times as long as basal width, tapering to narrowly rounded apex; bearing serrated scales and fine setae proximally, distal third covered with dense cuticular branched scales.

Pleopod 1 (Fig. 19 A) exopod and endopod with 42 and 19 plumose marginal setae; endopod nearly triangular, medial margin bearing a longitudinal fold fringed with fine setae; sympod mesial margin with 4 coupling hooks.

Pleopod 2 (Fig. 19 B) exopod and endopod with 39 and 19 plumose marginal setae; appendix masculina arising sub-basally, extending slightly beyond endopod (by about 0.2 its length), distal part folded with narrowly rounded apex, proximally with marginal cuticular scales; sympod with 4 distomesial coupling hooks, lateral margin with a long robust plumose seta.

Pleopod 3 (Fig. 19 C) exopod and endopod with 41 and 16 plumose marginal setae; sympod with 3 distomesial coupling hooks.

Pleopod 4 (Fig. 19 D) exopod lateral margin with 31 slender simple and numerous short setae (10 distally of and 21 under the transverse suture).

Pleopod 5 (Fig. 19 E, 20D) exopod lateral margin with 17 slender simple marginal setae only under the transverse suture, medial margin with a single marginal seta; endopod lateral margin fringed with fine setae on about one-third of distal length.

Uropodal rami (Fig. 16 A, 20A) subequal, not extending to pleotelsonic medial lobe apex; endopod with a prominent proximal tubercle, bearing scattered small tubercles over surface, all apically setose, distally oblique; exopod wider than endopod, distally with conical acute tip; lateral margin stout, straight, setose and tuberculate; medial margin rounded.

Subadult male. Cephalon, pereon and pleon lacking tubercles, dorsal surface covered with scattered short setae, densely in pleon and pleotelson surface. Pleotelson with trifid apex, medial lobe not extending well beyond the level of lateral lobes.

Female. Apart from primary sexual characters similar to sub-adult male, pleotelsonic medial lobe triangular, lateral lobe weak; uropod rami short and not reaching to the level of pleotelson apex, endopod distally concave (Fig. 16 F).

Remarks. Cymodoce delvarii can be recognized by the granular pleon and pleotelson, two prominent pleotelsonic ridges, and an oval domed boss. The new species differs from C. fuscina Schotte and Kensley, 2005 (known from Saudi Arabia, in the Persian Gulf), which has a pleotelson without a hemispheric dome and, very deep apical notch, and pereopod 7 with many long setae on the ischium superior margin. Examination of the holotype of C. spinula Yousuf & Javed, 2001 (ZMUC-CRU-3678, from Karachi, Pakistan, Fig. 21 D) showed that this species differs from C. delvarii in having a pleotelson with a very large domed boss, with longitudinal row of tubercles on either side, as well as a shallow apical notch.

Cymodoce richardsoniae Nobili, 1906 is similar to Cymodoce delvarii, the two species share two thickened parallel ridges on the pleotelson dorsal surface and uropod rami not reaching the end of the medial lobe of the pleotelsonic apex. However, C. richardsoniae clearly differs from C. delvarii in having less scattered tubercles on the pleon and pleotelson dorsal surfaces, three prominent tubercles on the lateral sides of the pleotelsonic bosses (rather than two), a tuft of dense long setae on anterior part the hemispheric dome, and uropodal exopod extended well beyond pleotelon apex with a row of simple setae on dorsomedial surface.

Etymology. The first author names this new species in honour of “Rais Ali Delvari”, a national hero of southern Iran in the early part of the 19th century.