Leucothoe minoculis, Kristine N. White & Traudl Krapp-Schickel, 2017

Kristine N. White & Traudl Krapp-Schickel, 2017, Red Sea Leucothoidae (Crustacea: Amphipoda) including new and re-described species, European Journal of Taxonomy 324, pp. 1-40 : 15-19

Leucothoe minoculis sp. nov.

urn:lsid:zoobank.org:act:3276B9C4-ECF6-4DB2-895F-938FAED8647D

Figs 6–7

Diagnosis

Head anterior margin oblique, produced, distal margin excavate with acute projection. Eyes round, rather small. Accessory flagellum present, 2-articulate. Maxilla 1 palp 1-articulate. Gnathopod 1 coxa longer than wide; carpus curved, very thin; propodus proximally not inflated, rectangular; dactylus reaching 0.3 times propodus length. Gnathopod 2 basis rectangular; carpus distally rounded, serrate, with one strong apical spine; propodus palm partially concave with many small tubercles distally. Pereopods 5–7 bases narrowly expanded; meri and carpi posteriorly lengthened and moderately widened.

Etymology

Stressing the fact that this species has smaller eyes than the other ones; ‘ minoculis ’ (composed from Latin ‘ minor ’ = less and ‘ oculi ’ = eyes), used as an adjective.

Type material

Holotype

ISRAEL: ♂, 5 mm, Red Sea, Eilat, stn 65, Apr.–May 1969, U. Schiecke leg. (ZMB 29752).

Paratype

ISRAEL: ♀, 3.5 mm, same data as holotype (slide MVRCr 7729).

Additional material examined

ISRAEL: 1 ♂, 3.5 mm, same data as holotype (slide MVRCr 7730); 2 specimens in alcohol, same data as holotype (MVRCr).

Description

Male

LENGTH. 5 mm.

HEAD. Anterior margin medially acute, anterodistally oblique, inferiorly straight; eyes rather small, round. Antenna 1 length 0.5 times body length, flagellum 6-articulate, peduncle article 1 width subequal to article 2, accessory flagellum present, 2-articulate. Antenna 2 length 0.4 times body length, shorter in length than antenna 1, flagellum 6-articulate. Mandibular palp ratio of articles 1–3 1.0:2.2: 1.6, article 2 with several marginal and distal setae, article 3 with 1 distal seta, incisors weakly dentate; left mandible with 5 raker spines, lacinia mobilis large, weakly toothed. Maxilla 1 palp 1-articulate, articulation not well visible, with distal slender setae; outer plate with 5 distal robust setae and additional slender setae. Maxilla 2 inner plate with marginal and distal slender setae, outer plate with distal slender setae. Maxilliped inner plates distal margin rounded, with short simple robust setae; outer plate inner margin smooth, reaching 0.3 times palp article 1; palp article 4 subequal in length with article 3, distally acute.

PErEON. Coxae 1–4 relative widths 1.0: 1.1: 1.0:1.3. Gnathopod 1 coxa smooth, anterodistal margin produced, rounded, distal margin rounded, posterior margin curved; basis distally not expanded, anterior margin with 2 short setae, posterior margin bare; ischium bare; carpus curved, distal length 30 times width, distally very narrow, anterior margin with small short setae; propodus straight, palm smooth with short setae; dactylus smooth, reaching 0.3 times propodus length. Gnathopod 2 coxa subquadrate, wider than coxa 3, smooth, margins straight; basis not expanded, stout, anterior margin with 13 medium setae, posterior margin bare; ischium bare; carpus 0.5 times propodus length, curved, setose, distally rounded, serrate; propodus primary mediofacial setal row reaching 0.8 times propodus length, secondary mediofacial setal row with three setae, anterior margin gently curved, smooth, palm with many small tubercles; palmar corner clearly defined as prominent hump, remaining posterior margin straight; dactylus curved, proximal margin smooth, bare, anterior margin distally acute, reaching 0.6 times propodus length. Pereopod 3 coxa smooth, anterior margin rounded, distal margin slightly rounded, posterior margin straight. Pereopod 4 coxa trapezium-shaped, smooth, antero-distally produced, anterior margin straight, longer than straight posterior one, distal margin scarcely rounded. Pereopods 5–7 bases widthlength ratios 1:1.9, 1: 1.9, 1: 1.7, posterior margins smooth and bare; Pereopods 5–6 bases with anterior and posterior margin nearly parallel, pereopod 7 basis longer and wider than the ones of pereopods 5 and 6, posteriorly moderately rounded.

PLEON. Epimera 1–3 bare, epimeron 3 posteroventral corner rounded. Uropods 1–3 relative lengths 1.0: 0.7: 1.0. Uropod 1 peduncle subequal in length with rami, outer ramus 0.9 times inner ramus length. Uropod 2 peduncle subequal in length with outer ramus, inner ramus about 1.4 times outer ramus length. Uropod 3 peduncle 1.2 times inner ramus length, outer ramus 0.9 times inner ramus length. Uropods 1–3 inner and outer rami bare. Telson 1.8 times longer than wide, apex rounded, beset with two short setae.

Female (sexually dimorphic characters) Similar in all aspects to male.

Depth range

Unknown.

Remarks

Leucothoe minoculis sp. nov. resembles L. reimeri sp. nov. in the shape of the head and the narrowly expanded bases on pereopods 5–7. It differs in having a very small eye, and in the shapes of the coxae. This species is unique in having a 2-articulate accessory flagellum, not documented in any other known species of Leucothoe .

Distribution

Red Sea (present study).

Figures

Fig. 6. Leucothoe minoculis sp. nov., holotype, ♂, length 5.0 mm (MVRCr 7729).

Fig. 7. Leucothoe minoculis sp. nov., holotype, ♂, 5.0 mm (MVRCr 7729); paratype, ♀, 3.5 mm (MVRCr- 7729).