Uromunna alyamanii sp. nov.

Figs 5 C, 6, 7, 8

Etymology.

The species is named in honour of Dr Faiza Yousef Al-Yamani, a pioneering figure who established the Oceanography Program at the Environment and Life Sciences Research Center at Kuwait Institute for Scientific Research (KISR) in 1991.

Type material.

Holotype: • ♂, 0.78 mm (ZMH-K-64937); KUWAIT. Quaruh Island; 28°49.105'N, 48°46.553'E; 10. XI. 2014; V. Grintsov leg. Paratypes: • 1 ♀, 0.88 mm (ZMH-K-64938), same data as the holotype • 1 ♀, 0.78 mm (ZMH-K-64939), Al-Khiran; 29°38'48.47"N, 48°23'28.68"E; 05. I. 2015; V. Grintsov leg. • 2 ♀♀, up to 0.75 mm (ZMH-K-64940), Auha Island; 29°22.32'N, 48°26.27'E; 10. II. 2016; V. Grintsov leg. • 2 ♀♀, up to 0.8 mm, 1 ♂, 0.725 mm, 1 slide (ZMH-K-64941), Al-Nuwaiseeb; 28°34.792'N, 48°24.078'E; 07. I. 2015; V. Grintsov leg. • 1 ♀, 0.787 mm, 1 slide (ZMH-K-64941), Failaka Island; 29°28.049'N, 48°17.838'E; 22. XII. 2014; V. Grintsov leg.

Diagnosis.

Pleotelson 1.26 times longer than wide, 0.31 times of whole body, and lateral margins each with 2 denticles. Maxillipedal endite with three coupling hooks. Male pleopod 1 distal margin medial lobes convex, each lobe with three setae. Pleopod 2 protopod elongate, with distally rounded apex; endopod stylet extending just beyond apex of protopod, about 0.7 times as long as protopod. Pleopod 4 exopod distal tip with 1 elongate plumose seta.

Description.

Male: Body (Fig. 6 B) length 0.78 mm; about 2.1 times as long as wide.

Head (Fig. 6 B) 0.65 times as long as wide; anterior margin straight; preocular lobes distinct and projecting. Eyes present, ommatidia on eye lobe outer margin, with 12 ommatidia.

Pereon (Fig. 6 B) dorsal surface smooth; pereonite 1 narrowest; pereonite 3 widest and longest; coxae visible on pereonites 2–7, each with 1–2 small setae; pereonites 5 – 7 turned back; lateral margins rounded; pereonite 7 longer then pereonite 6, about 1.5 times as long as pereonite 6.

Pleonite 1 small, about 0.4 times as long as wide, without dorsal setae.

Pleotelson (Figs 6 B, 5 C, 6 C) about 1.26 times longer than wide, pyriform, lateral margins each with 2 small lateral denticles; dorsal surface covered with 16 simple setae.

Uropod (Fig. 6 C) cylindrical, endopod bearing 6 lateral and apical setae; exopod minute, with one simple seta.

Antennula (Fig. 6 D) peduncular article 1 shorter than article 2; article 2 with 2 simple and 2 small sensory palmate setae sub distally; article 3 about 0.5 length of article 2, with 1 simple seta distally; flagellum with three articles, article 2 longest; article 3 distally with 1 long aesthetasc.

Antenna (Fig. 6 E) about 0.8 times as long as body; antennal flagellum shorter than peduncular articles, with 8 articles.

Mandible (Fig. 6 F) incisor process and lacinia mobilis with 4 cusps; spine row with 4 robust serrate setae. Palp articles 1 and 2 without setae, third article 0.55 times as long as article 2, with 2 serrated setae apically.

Maxillula (Fig. 6 G) lateral lobe with 10 robust apical setae; medial lobe with 4 robust serrate setae on distal margin.

Maxilla (Fig. 6 H) lateral and mesial lobes each with 4 and 3 pectinate robust apical setae; medial lobe with 8 robust setae along distal margin, some of them serrated.

Maxilliped (Fig. 6 I) endite distal margin with 2 fan-shaped setae, 4 serrate setae, and 3 sub marginal serrated setae dorsally; mesial margin with 3 coupling hooks; palp article 1 bearing short seta on distomesial corner; article 2 sub equal length to article 3, with 3 setae medially and 1 seta on distolateral corner; article 3 with 4 setae medially and 1 seta laterally; article 4 subequal in length to article 3, with 2 setae distomedially and 1 seta laterally; article 5 with 4 setae distally.

Pereopod 1 (Fig. 7 A) shorter than pereopods 2 – 7; basis 2.6 times as long as greatest width, superior margin with 1 and inferior margin with 2 small setae; ischium about 0.7 times as long as basis, superior margin with 2 and inferior margin with 1 small setae; merus longer than carpus, 0.75 times as long as ischium, superior margin with 2 and inferior margin with 1 robust setae distally; carpus with 4 robust bifid setae on inferodistal corner, inferior margin with 1 marginal and 4 submarginal long simple setae, superior margin with 1 long simple seta medially; propodus 1.75 times as long as carpus, inferior margin fringed with fine setae, bearing 2 robust submarginal setae, superior margin with 1 long simple seta medially and 2 simple setae distally; dactylus with 2 subapical simple setae, a long unguis, and a long accessory claw.

Pereopod 2 (Fig. 7 B) basis about 3.1 times as long as greatest width; ischium about 0.7 times as long as basis, with 3 long setae on inferior margin and 1 long seta on superior margin; merus about 0.45 times as long as carpus, inferior margin with 2 and superior margin with 4 simple setae; carpus about 0.9 times as long as propodus, inferior margin with 3 robust setae, superior margin with 1 seta medially and 1 simple and 1 plumose setae distally; propodus inferior margin with 2 robust bifid setae, superior margin with 5 long simple setae; dactylus with a narrow accessory claw, unguis longer than dactylus.

Pereopod 4 (Fig. 7 C) similar to pereopod 5 (Fig. 7 D), propodus about 1.5 times as long as carpus, with 4 robust bifid setae on inferior margin and 7 long simple setae and 1 sensory palmate seta on superior margin.

Pereopod 7 (Fig. 7 E) basis about 2.8 times as long as greatest width; ischium about 0.86 times as long as basis, with 3 long setae on inferior margin and 2 long setae on superior margin; merus about 0.46 times as long as carpus; carpus with 4 robust setae on inferior margin and 5 robust setae on superior margin; propodus about 1.5 times as long as carpus, inferior margin with 6 robust bifid setae, superior margin with 8 long simple setae and 1 sensory palmate seta; unguis 1.24 times as long as dactylus.

Pleopod 1 (Fig. 8 A) consists of two coalescent halves, each half 4.5 times longer than maximum width; proximal part enlarged and tapering distally, distal margin narrowly rounded, each lobe with three setae distally.

Pleopod 2 (Fig. 8 B) protopod elongate, with distally rounded apex, about 2.2 times longer than wide, with 3–4 subapical setae; endopodal stylet, elongate, medially swollen but becoming narrower until distal tip, without ornamentation, extending just beyond apex of protopod, endopod stylet length about 0.7 protopod lengths.

Pleopod 3 (Fig. 8 C) protopod as long as width; endopod 1.8 times longer than wide, with three plumose setae apically; exopod with two articles, proximal article 2.4 longer than wide, lateral margin fringed with fine setae, distal article 1.6 times longer than wide, with 1 simple seta distally.

Pleopod 4 (Fig. 8 D) exopod with 2 articles, article 1 lateral margin fringed with dense fine setae, article 2 lateral margin with a few fine setae; with 1 elongate plumose seta distally.

Penes (Fig. 8 E) fused along basal part, well separated at distal part, tapering to rounded apices.

Female (Figs 5 C, 6 A) body about 1.9 times longer than wide; widest at pereonite 3. Largest female length 0.74 mm. Female operculum (Fig. 8 A) length 1.25 width, with one pair of subterminal elongate setae.

Remarks.

Uromunna alyamanii sp. nov. shares similarities with U. naherba Esquete, Wilson & Troncoso, 2014 from NW Iberian Peninsula, Spain, and U. jejuensis Kim, Lee & Karanovic, 2023 from the Mun Island, Sea of Japan. These similarities include the appearance of mouthparts, pereopods, and pleopods, especially a round distal apex of male pleopod 1 with three pairs of apical setae, the presence of denticles on the pleotelsonic lateral margins, and a female operculum with a terminal pair of setae. However, the present species also have distinct differences, such as a pleotelson with 2 lateral margin denticles on each side, a feature not found in the latter species.

The new species differs from U. sheltoni (Kensley, 1977) from South Africa, which has the distally concave pleopod 1, with 4 short apical setae (vs. distally rounded, with 3 short setae in the present species), and the shorter endopodal stylet of pleopod 2, which does not reach beyond the apex of the ramus.