Leiogalathea aeneas Rodríguez-Flores & Macpherson & Machordom 2019, n. sp.

Field: Agricultural and Biological Sciences (Life Sciences)

Leiogalathea aeneas n. sp. (Figs. 2, 10B) Galathea agassizii.— A. Milne Edwards & Bouvier 1900: 282 (part), pl. 6, fig. 7.— Bouvier 1922: 43.— d'Udekem d'Acoz 1999: 160 (compilation). Type material. Holotype: NW Africa. M 36-98 AT149, 25°31.5'N, 16°02.2'W, 658–888 m, 24 February 1975: F 7.6 mm (SMF 51246). Paratypes: Morocco. OTSB 14 Stn 8966, 31°35'N, 10°07'W, 686–742 m, 2 August 1976: 1 M 8 mm (CEAB.CRU.241 I). NW Africa. TALISMAN Stn 34, 32°27'N, 12°19'W, 836–868 m, 13 June 1883: 1 F 9.3 mm (MNHN-IU-2019- 2004).—Stn 37, 31°34'N, 12°43'W, 1050 m, 21 June 1883: 2 M 3.8–6.7 mm, 1 ov. F 5.3 mm (MNHN-IU-2019- 2005).—Stn 63, 26°18'N, 17°12'W, 640 m, 8 July 1883: 1 M 5.0 mm (MNHN-IU-2019-2002).—Stn 71, 25°39'N, 18°18'W, 640 m, 9 July 1883: 1 ov. F 5.2 mm (MNHN-IU-2019-2001).—Stn 73, 640 m, 9 July 1883: 7 M 5.2–7.3 mm, 10 F 4.5–6.4 mm (MNHN-IU-2019-2003).—Stn 72, 25°39'N, 18°22'W, 882 m, 9 July 1883: 1 M 9.8 mm, 1 ov. F 6.4 mm (MNHN-IU-2019-2006).—Stn 72, 25°39'N, 18°22'W, 882 m, 9 July 1883: 1 M 6.7 mm, 1 ov. F 7.0 mm (MNHN-IU-2019-2007). NW Africa. M36–98 AT149, 25°31.5'N, 16°02.2'W, 658–888 m, 24 February 1975: 8 M 6.0– 8.5 mm, 4 F 4.4– 6.5 mm (SMF39233). Congo. GERONIMO Stn 2–221, 3°02'S, 09°16'E, 348 m, 6 September 1963: 1 M 7.3 mm (MNHN-IU-2016- 422). Etymology. From the name Aeneas, the protagonist of the Aeneid. The name is considered a substantive in apposition. Description. Carapace: 1.3 × as long as broad. Mid-transverse ridge interrupted (holotype) or uninterrupted, preceded by deep cervical groove, followed by 4 medially interrupted transverse ridges. Lateral margins convex, with 6 spines: first spine anterolateral, well-developed; spine on hepatic margin smaller than first spine, 2 welldeveloped spines on anterior branchial margin, posterior spine smaller, and 2 spines on posterior branchial margin, last spine small. Rostrum horizontal, dorsally flattish, 1.6–1.8 × as long as broad, length 0.4 × and breadth 0.2 × that of carapace; lateral margin with 1–5 spines, 1 or 2 proximal teeth well-developed, the others rudimentary and decreasing in size distally. Sternum: Sternite 3 moderately broad, 2.5–2.7 × as wide as long, anterolaterally obtuse, not strongly produced, anterior margin with a median shallow notch flanked by denticulate low lobes. Sternite 4 broadly contiguous to sternite 3, denticulate on anterolateral angles; surface depressed in midline, smooth; greatest width 2.4 × that of sternite 3, 2 × as wide as long. Abdomen: Tergites 2–3 each with 2 elevated transverse ridges, tergite 4 with transverse ridge, tergites 5–6 smooth; tergite 6 with transverse posteromedian margin. Eye: Ocular peduncle slightly longer than broad, cornea subglobular, maximum corneal diameter 0.7 × rostrum width, cornea as broad as eyestalk. Antennule: Article 1 with distomesial angle granulated; lateral margin smooth along distal part. Antenna: Article 1 with strong distomesial spine overreaching end of article 2; article 2 with strong distomesial spine longer than distolateral spine and reaching end of article 3; articles 3 and 4 unarmed. Mxp3: Ischium as long as merus measured along extensor margin; flexor margin sharply ridged, terminating in small spine; extensor margin unarmed; crista dentata finely denticulate; merus having flexor margin with strong median spine and distally serrated, extensor margin with distal spine. P1: 2.8–3.3 (males), 2.2–2.5 (females) × carapace length, with numerous short striae, and uniramous setae scattered on merus to dactylus. Merus 0.9 length of carapace, 2.2 × as long as carpus, with strong mesial and distal spines, and some scattered dorsal spines. Carpus 0.8 × as long as palm, 1.5 × as long as broad, dorsal surface with scattered small spines, mesial margin with 4 or 5 strong spines, lateral margin unarmed. Palm 1.6 × as long as broad, armed with small spines in irregular longitudinal rows on mesial and lateral margins, dorsal surface unarmed. Fingers as long as or slightly longer than palm; fixed finger unarmed; movable finger occasionally with proximal mesial spine. P2–4: Moderately stout, somewhat compressed laterally, with short striae on dorsal surface; with sparse long and thick setae on ischium to dactylus. Meri successively shorter posteriorly (P3 merus 0.9 × length of P2, P4 merus 0.9 × length of P3 merus). P2 merus 0.7 × carapace length, 4.8 × as long as broad, 1.4 × as long as P2 propodus; P3 merus 0.7 × carapace length, 4.2 × as long as broad, P4 merus 0.5 × carapace length, 3.2 × as long as broad, as long as P4 propodus; extensor margin with a row of 7 or 8 proximally diminishing spines in P2–P3, unarmed on P4; lateral surface unarmed; flexor distal margin with well-developed distal spine and sparse projecting scales. Carpi with 3 or 4 spines on extensor margin on P2–3, unarmed on P4, lateral side smooth; flexor margin with small distal spine. Propodi 5.2–6.4 × as long as broad in P2–4, flexor margin with 4 or 5 movable spinules. Dactyli 0.6 length of propodi; distal claw strong, moderately curved; flexor margin nearly straight, with 8 small teeth along entire margin decreasing in size proximally, each with slender movable spinule, ultimate tooth equidistant between base of distal claw and penultimate tooth. Colour in life. Ground colour pale rose to bright rose, pereiopods whitish, P1 coloured at tips (Bouvier 1922). Genetic data. No data. Distribution. Coast of Morocco, Canary Islands, Cape Verde Islands, coast of Sahara, in corals, from 640 to 1642 m. Remarks. Leiogalathea aeneas belongs to the group of species having a spine on the hepatic margin of the carapace. The closest relatives are L. agassizii from the Caribbean Sea and L. ascanius from tropical west Africa (see below, under the Remarks of these species).