Cymodoce brucei, Khalaji-Pirbalouty, 2016

Khalaji-Pirbalouty, Valiallah, 2016, A new species of Cymodoce from Iran (Crustacea: Isopoda: Sphaeromatidae) with remarks on the status of Cymodoce manorii (Nooruddin, 1965) comb. nov. and Cymodoce spinula Yousuf & Javed, 2001, Zootaxa 4084 (2), pp. 267-276 : 269-274

publication ID	https://doi.org/ 10.11646/zootaxa.4084.2.6
publication LSID	lsid:zoobank.org:pub:8A7F15E8-A69B-4418-8A9F-A25C75C143D8
DOI	https://doi.org/10.5281/zenodo.6088283
persistent identifier	https://treatment.plazi.org/id/03EC5E73-FF9C-F965-FF34-F98C1B58F8DF
treatment provided by	Plazi
scientific name	Cymodoce brucei
status	sp. nov.

Treatment

Cymodoce brucei View in CoL sp. nov.

( Figs 2–5 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 )

Material examined. All material from Iran, northern Oman Sea.

Holotype. ♂ (5.1 mm), Sistan-Baluchestan Province , Djod village, 19 January 2015, 25°26’592”N, 59°31’004”E, low intertidal, rocky cobbles on green algae, coll. S. Ebrahimzadeh and R. Naderloo ( ZMH –K– 42599).

Paratypes. 1 ♂ (4.8 mm), 1 sub-adult ♂ (4.4 mm), 1♀ (4.1 mm), ( ZUTC 5483 ) Sistan-Baluchestan Province , Abd Village, 29 December 2013, 25°34’845”N, 58°48’209”E, low intertidal, rocky shore, on green algae, coll. V. Khalaji and A. Kazmi ( ZUTC 5483 ) .

Diagnosis. Head dorsal surface with row of 6 small tubercles, pereonites 1–3 smooth, pereonites 5–7 with row of continuous tubercles. Pleotelson with two prominent longitudinal ridges proximally, dorsomedial surface with two prominent tubercles, each flanked on either lateral side by larger prominent tubercle, and followed by large prominent conical boss; posterior part possess large prominent tongue-like projection in midline. Uropod rami extending just beyond apex of pleotelson medial lobe, exopod longer than endopod with acute apex.

Description of male. Body 2.1 times as long as greatest width (pereonite 6). Head dorsal surfaces with row of 6 small tubercles; rostral process visible slightly in dorsal view. Pereonites 1–3 smooth, 4 with transverse row of non-continuous weak tubercles; pereonites 5–7 with row of continuous tubercles ( Fig. 2A View FIGURE 2 ).

Pleon with two, long, straight, separate and parallel sutures at each side, dorsally bearing numerous scattered uneven tubercles of various sizes, with two pronounced tufts of simple long setae on each side; posterior margin with two extensions; posterolateral margins with fringe of very long sub-marginal setae.

Pleotelson bearing scattered tubercles of various sizes over most of surface, with 2 prominent longitudinal ridges proximally, middle side bearing 4 prominent tubercles, followed by large prominent conical boss either side of midline, all apically setose; posterior to bosses, pleotelson bearing 1 prominent tongue-like projection in midline; pleotelson apical lobes blunt, medial lobe extending beyond level of lateral lobes ( Figs. 1D View FIGURE 1 , 2A, B View FIGURE 2 ).

Antennula ( Fig. 2D View FIGURE 2 ) peduncle article 1 bearing scattered small setae and some SPS, article 2 with 4 small SPS on ventral margin, article 3 about 1.9 times as long as article 2; flagellum with 14 articles, article 1 bearing 2 small SPS, articles 4–14 each bearing single aesthetasc and 1 simple seta.

Antenna ( Fig. 2E View FIGURE 2 ) peduncle articles 1 fringed with small setae dorsally, article 5 about 1.4 times as article 4; flagellum with 13 articles.

Epistome ( Fig. 2F View FIGURE 2 ) with triangular acute apex, anterolateral margin straight, lateral margins concave.

Maxillula ( Fig. 3A View FIGURE 3 ) lateral endite with long fine setae on mesial and lateral margins, apical margin with 4 simple RS and 4 deeply serrated RS; mesial endite with 4 long, robust, comb and 1 short simple setae.

Maxilla ( Fig. 3B View FIGURE 3 ) lateral and middle endites each with 8 curved pectinate RS; mesial endite with 3 rarely plumose, 5 long and 3 shorter robust combs, and 1–2 slender simple setae.

Left mandible ( Fig. 3C View FIGURE 3 ) lacinia mobilis with 3 cusps, spine row of 6 serrate spines. Palp article 1 longer than 2, articles 2 and 3 distolateral margins with approximately 18 and 14 biserrate setae.

Maxilliped ( Fig. 3D View FIGURE 3 ) endite lateral margin sinuate, mesial margin with single coupling hook, distal margin with 9 blunt rarely plumose or circumplumose RS; palp articles 2–4 with single simple seta on superiodistal angle.

Pereopod 1 ( Fig. 3E View FIGURE 3 ) basis about 2.4 times as long as greatest width, ischium superior margin with 1 curve, acute RS on proximal corner and 1 long and 1 small RS on medial angle; merus, carpus and propodus inferior margins fringed with simple fine setae; merus superodistal angle with 2 simple RS, inferior margin with 2 biserrate RS and single long apically palmate seta; carpus inferior margin with 2 biserrate RS and 1 single long apically palmate seta; propodus inferior margin with 4 biserrate RS; dactylus inferior margin with fine setae and cuticular scales, secondary unguis simple.

Pereopod 2 ( Fig. 3F View FIGURE 3 ) basis about 2.8 times as long as greatest width, with 2 small SPS; ischium superior margin with 1 curve, acute RS on proximal corner and 1 RS on medial angle; merus, carpus and propodus inferior margins fringed with simple fine setae; merus superodistal angle with 2 RS, inferior margin with 3 RS and 1 single long apically palmate seta; carpus inferior margin with 2 RS, and 1 long apically palmate seta, superodistal angle with 2 RS and 1 SPS; propodus inferior margin with 3 biserrate RS, superodistal angle with 1 long simple seta and a single SPS.

Pereopod 3 ( Fig. 4A View FIGURE 4 ) is similar to pereopod 2. Pereopods 4 ( Fig. 4B View FIGURE 4 ) and 5 ( Fig. 4C View FIGURE 4 ) are similar as illustrated.

Pereopod 6 ( Fig. 4D View FIGURE 4 ) basis about 2.8 times as long as greatest width, inferodistal angle with 2 simple RS, superior margin with several simple and 3 SPS; ischium superior medial angle with 4 RS; merus, carpus and propodus inferior margins fringed with simple fine setae; merus superodistal margin with 3 long RS, inferior margin with 2 roust biserrate setae and single long apically palmate seta; carpus inferior margin with 2 biserrate RS and single long apically palmate seta, distal margin with 2 biserrate RS, superodistal corner with 2 long RS; propodus superodistal corner with 3 slender and 1 single SPS, inferior margin with 4 biserrate RS. Articles merus, carpus, propodus and dactylus of pereopods 7 ( Fig. 4E View FIGURE 4 ) and 6 are similar except in some details such as in number of biserrate RS on distal margin of carpus.

Penial processes about 8.2 times as long as basal width, tapering to narrowly rounded apex; distal half covered with dense cuticular branched scales ( Fig. 5F View FIGURE 5 ).

Pleopod 1 ( Fig. 5A View FIGURE 5 ) exopod and endopod with 34 and 21 PMS; exopod proximally with single RS on lateral angle; endopod medial margin bearing longitudinal fold fringed with thin setae; sympod mesial margin with 3 coupling hooks, lateral marine fringed with fine setae.

Pleopod 2 ( Fig. 5B View FIGURE 5 ) exopod and endopod with approximately 31 and 18 PMS; appendix arising basally, extending beyond endopod (by about 0.3 its length), tapering evenly to narrowly rounded apex; sympod with 3 distomesial coupling hooks, lateral margin fringed with thin setae, distolateral corner with long plumose RS.

Pleopod 3 ( Fig. 5C View FIGURE 5 ) exopod and endopod with approximately 35 and 19 PMS; exopod sub-elliptical, narrowing proximally, with transverse suture; sympod with 3 distomesial coupling hooks, lateral margin fringed with thin setae, distolateral corner with single long plumose seta.

Pleopod 4 ( Fig. 5D View FIGURE 5 ) endopod with pronounced and curved apical lobe, bearing 1 stout apical seta; exopod bearing 1 single apical stout plumose seta, lateral margin with approximately 25 slender simple setae (7 distally of and 18 under transverse suture), and numerous fine setae; sympod distolateral corner with single plumose seta.

Pleopod 5 ( Fig. 5E View FIGURE 5 ) exopod with 5 scale patches (3 distally of and 2 under transverse suture), lateral margin with 10 slender simple marginal setae (all under transverse suture); endopod distolateral margin fringed with fine setae on 0.4 its length.

Uropodal rami ( Fig. 1E View FIGURE 1 , 2A View FIGURE 2 ) extending beyond pleotelsonic apex; endopod, distally oblique and setose; exopod wider than endopod, about 1.2 as long as endopod, distally with conical acute tip; lateral margin stout, straight, setose and tuberculate.

Subadult male. Head, pereon and pleon lacking tubercles, dorsal surface covered with scattered short setae. Pleotelson lacking prominent tubercles and bosses, with trifid apex, medial lobe not extending well beyond level of lateral lobes. Penes with separate, short and broad rami; Appendix masculina joined with endopod of pleopod 2, bearing single plumose seta on rounded apex.

Female. Apart from primary sexual characters similar to sub-adult male as illustrated; pleotelsonic medial lobe triangular, lateral lobe weak; uropod rami short and not reaching to the level of pleotelson apex ( Fig. 1C View FIGURE 1 ).

Remarks. Cymodoce brucei sp. nov. can be identified by a pleotelson with two prominent longitudinal ridges, four prominent tubercles on middle side, followed by two large prominent conical bosses, and posterior margin with a prominent tongue-like projection. Moreover, C. brucei has a uropodal exopod longer than the endopod like C. alis Barnard, 1955 , from South Africa, while in C. fuscina Schotte & Kensley, 2005 , the uropod has equal rami, and most Cymodoce species (see Harrison & Holdich 1984) have the uropodal exopod shorter than the endopod. In addition C. brucei , as some other species (e.g. C. truncata Leach, 1814 and C. zanzibarensis Stebbing, 1910 ), has a truncate uropodal endopod, whereas, several species have an endopod with acute, apical projection (e.g. C. bipapilla Harrison & Holdich, 1984 ; C. longistylis Miers, 1884 ; C. pelsarti Tattersall, 1922 ).

The new species is most similar to C. fuscina Schotte and Kensley, 2005 (known from Saudi Arabia, Persian Gulf). The two species share a pleotelson with two thickened parallel ridges on the dorsal surface, several prominent tubercles, and lack a domed boss; the shape of penial process and pleopod 2 appendix masculina are both also similar. Examination of the type material (USNM 280292) of Cymodoce fuscina showed that it differs from C. brucei in having a pleotelson with relatively slender, equal in length, and distally rounded apical lobes, uropodal exopod equal in length to endopod, and pereopod 7 with many long setae on the ischium superior margin and merus and carpus inferior margins. In addition, C. fuscina has a small knob at midline of the posterior region (instead of tongue-like projection in C. brucei ).

Etymology. This species is named for Dr Niel L. Bruce (Museum of Tropical Queensland, Queensland Museum, Townsville) in recognition of his many years of contributions to the taxonomy of the western Indian Ocean Isopoda .