Cirolana tarahomii, Khalaji-Pirbalouty, Valiallah & Wägele, Johann-Wolfgang, 2011

Khalaji-Pirbalouty, Valiallah & Wägele, Johann-Wolfgang, 2011, Two new species of cirolanid isopods (Crustacea: Isopoda: Cirolanidae) from Qeshm and Kish Islands in the Persian Gulf, Zootaxa 2930, pp. 33-46 : 39-42

publication ID	https://doi.org/ 10.5281/zenodo.278013
DOI	https://doi.org/10.5281/zenodo.5475177
persistent identifier	https://treatment.plazi.org/id/03D887BC-2C68-1618-FF5D-C714FBA54DBF
treatment provided by	Plazi
scientific name	Cirolana tarahomii
status	sp. nov.

Treatment

Cirolana tarahomii View in CoL sp. nov.

( Figs 5–8 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 )

Material examined. Holotype. Male (7.5 mm), Qeshm Island, northwestern coast, Basaeeduo, sandy/rocky shore, 0 7 May 2008, 26°36’N, 55°16’E; coll. A. Behpouri ( ZMH –K– 42590).

Paratypes. 1 female (6 mm), same data as holotype ( ZMH –K– 42591); 1 ovigerous female (7.1mm), Qeshm Island, Southwestern coast, Dustku, sandy/rocky shore, 0 7 May 2008, 26°33’N, 55°21’E; coll. R. Naderloo ( ZMH – K– 42592); 2 males (5.1, 4 mm), 2 females (4, 3.5 mm), 1 juvenile (3.1 mm), Kish island, Derakht sabz, sandy beach, 29 April 2010, 26°34’N, 53°58’E, coll. V. Khalaji-Pirbalouty ( ZUTC Iso. 1099).

Diagnosis. Body around 2.7 times as long as greatest width; pentagonal frontal lamina well extended anteriorly and anterior part overlapped by a downward projection of the rostrum; the posterior lateral margins of pleonite 3 are produced, and largely overlap the lateral margin of pleonite 4; appendix masculina 1.2 times as long as endopod, distally acute with bifid apex; pleotelson with broadly rounded apex, posterior margin with 8 robust marginal setae; uropodal endopod extending slightly beyond pleotelsonic apex, apically sub-bifid, mesial margin roundly convex with 5 robust setae, lateral margin weakly convex with 2 robust setae; exopod shorter than endopod, lateral margin with 8 robust setae, medial margin with 3 robust setae.

Description of male. Body 2.75 times as long as greatest width, widest at pereonite 5, dorsal surface smooth ( Figs 5 View FIGURE 5 A, 9B). Head with compelet interocular furrow and weak rostral point. Pereonite 4–7 coxal plates with entire oblique carina.

Pleon with pleonite 1 largely concealed by pereonite 7; pleonite 3 with posterolateral margins extending to posterior margin of pleonite 5, narrowly rounded; pleonite 4 clearly extending beyond posterior margin of pleonite 5 ( Fig. 5 View FIGURE 5 A).

Pleotelson 0.75 times as long as anterior width, lateral margins convex, with broadly rounded apex, posterior margin with 8 robust marginal setae, each set within indentation, 2–3 plumose setae set between robust setae; apex bearing a small notch with two short simple setae ( Fig. 1 View FIGURE 1 F).

Antennule ( Fig. 5 View FIGURE 5 C) peduncle articles 1 and 2 fused but suture still visible, article 3 shorter than combined lengths of articles 1 and 2; flagellum with 10articles, second of which is longst, articles 2–9 each bearing aesthetascs.

Antenna ( Fig. 5 View FIGURE 5 D) peduncle article 5 longr than others, about 1.2 times as long as article 4; flagellum with 30articles, extending to posterior of pereonite 4.

Frontal lamina ( Fig. 5 View FIGURE 5 E) 2.4 times as long as greatest width, lateral margins converging slightly toward base, anterior margin rounded, anterolateral part concave.

Left mandible ( Fig. 6 View FIGURE 6 C) molar process anterior margin with 16 sub-marginal flat teeth, fringed with dense fine marginal setae; proximally with some long simple setae, spine row composed of 11 spines; palp article 1 with 2 distolateral long simple setae, palp article 3 with 26–28 robust biserrate setae.

Maxillule ( Fig. 6 View FIGURE 6 A) lateral endite with 9 long robust (weakly serrated) and 3 small robust setae, mesial margin with 4 acute simple setae; mesial endite with 3 stout circumplumose setae and 2 short setae.

Maxilla ( Fig. 5 View FIGURE 5 B) lateral and middle endites each with 4 and 12 long simple setae; mesial endite with 10 circumplumose and 6 simple setae.

Maxilliped ( Fig. 6 View FIGURE 6 D) endite with 5 long circumplumose setae and 2 coupling hooks; palp articles 2–4 lateral margins bearing distally serrated long setae, mesial margins with distally serrate or simple setae.

Pereopod 1 ( Fig. 7 View FIGURE 7 A) Pereopod 1 basis 2 times as long as greatest width; merus inferior margin with 4 molariform robust setae; carpus triangular, without robust setae; propodus inferior margin with 2 acute and 1 bluntly rounded robust seta. Pereopod 2 ( Fig. 7 View FIGURE 7 B) ischium inferior margin with 2 robust seta, superodistal corner with 2 biserrate and 1 long bifid robust setae; merus inferior margin with 1 molariform and 6 bifid and finely serrate medially robust setae as figured. Pereopod 3 ( Fig. 7 View FIGURE 7 C) similar to pereopod 2. Pereopod 4 ( Fig. 7 View FIGURE 7 D) intermediate in form between 3 and 5. Pereopod 6 ( Fig. 7 View FIGURE 7 F) similar to pereopod 7. Pereopod 7 ( Fig. 7 View FIGURE 7 G) merus supero-distal margin with 9 robust setae (2 bifid and 7 biserrate); infero-distal corner with 4 bifid robust setae; carpus distal margin with 15 robust setae (13 biserrate and 2 bifid).

Pleopod 1 ( Fig. 8 View FIGURE 8 A) exopod and endopod with 31 and 13 plumose marginal setae; endopod distally narrowly rounded, lateral margin straight; exopod ovate, with a single long simple seta on proximal lateral corner; sympod mesial margin with 5 coupling hooks and a single plumose seta, lateral margin with single robust seta. Pleopod 2 ( Fig. 9 View FIGURE 9. A B) exopod and endopod with 42 and 16 plumose marginal setae; appendix masculina arising basally, extending well beyond endopod by about 1.2 as long as endopod, distally acute with bifid apex, bearing small cuticular spines on most of surface; sympod mesial margin with 4 coupling hooks and 5 plumose seta, lateral margin with single robust seta.

Pleopod 3 ( Fig. 8 View FIGURE 8 C) exopod and endopod with 45 and 13 plumose marginal setae, exopod with a patch of serrate scales on mesial margin and partial transverse suture; sympod with 4 coupling hooks and 5 plumose setae.

Pleopod 4 ( Fig. 8 View FIGURE 8 D) similar to pleopod 3, exopod and endopod with 43 and 10 plumose marginal setae.

Pleopod 5 ( Fig. 8 View FIGURE 8 E) exopod with 48 plumose marginal setae, with a patch of serrate scales on mesial margin and partial transverse suture; endopod triangular, without marginal setae, with lobate medial corner proximally; sympod without coupling hook, with a single long robust seta on distolateral corner.

Penes ( Fig. 8 View FIGURE 8 F) separate and short, 0.8 times as long as basal width.

Uropod ( Fig. 1 View FIGURE 1 G) peduncle ventrodistal margin with 2 plumose and 2 robust setae, lateral margin with 1 medial short robust seta, medial margin with 6 plumose setae; endopod extending slightly beyond pleotelsonic apex, 1.7 times as long as greatest width, apically sub-bifid with some long simple setae, mesial margin roundly convex with 5 robust setae, lateral margin weakly convex with 2 robust setae; exopod shorter than endopod, 2.7 times as long as greatest width, apically sub-bifid with some long simple setae, lateral margin with 7–8 robust setae, medial margin with 3 robust setae.

Remarks. Bruce (1986) proposed three informal groups within Cirolana , among which is the distinctive ‘‘ parva- group ’’ (Bruce 1995). All species in this group are characterized by having a pentagonal frontal lamina with the anterior part overlapped by a downward projection of the rostrum, the lateral margin of the uropodal exopod has a continuous row of robust setae interspersed by plumose marginal setae, uropod apices are apically bifid, and posterior lateral margins of pleonite 3 are extended and largely overlap the lateral margin of pleonite 4. The specific characters that permit identification of Cirolana tarahomii sp. nov. are: frontal lamina lateral margins converging slightly toward base, the extended distal margin with narrowly rounded apex; pleotelson with a broadly rounded apex, and uropodal rami apices are sub-bifid. Among the Indian Ocean species C. tarahomii is most similar to C. aldabrensis Schotte & Kensley, 2005 (from the Seychelles), but the latter differs in having a frontal lamina with parallel lateral margins without extension on the distal margin, a pleotelson with narrowly rounded apex and six robust setae, an uropodal exopod with an acute apex and five robust setae on lateral margin, and longer penial processes. Cirolana tarahomii also differs from the C. hesperia Bruce 1986 (from Western Australia) that has an uropodal exopod with acute apex, an endopod medial margin with six robust setae, pereopod 1 with dense marginal setae on the carpus and propodus inferior margins, and a longer appendix masculina without bifid apex. Cirolana meseda Hobbins & Jones, 1993 from the Red Sea (paratype material SMF, 21942) differs from C. tarahomii in having an elongate pleotelson with 10 robust marginal setae, uropod rami with very acute apices, and exopod and endopod medial margins with 5 and 6 robust setae, respectively.

Etymology. The species named in memory of Dr Sayed Mustafa Tarahomi, academic member of Ferdowsi University of Mashhad, Iran who unexpectedly passed away during field collection.