Microphasmoides vitjazi Vinogradov, 1960

Zeidler, Wolfgang, 2009, A review of the hyperiidean amphipod superfamily Lanceoloidea Bowman & Gruner, 1973 (Crustacea: Amphipoda: Hyperiidea), Zootaxa 2000, pp. 1-117 : 93-96

Microphasmoides vitjazi Vinogradov

( Figs 35 & 36)

Microphasmoides vitjazi Vinogradov, 1960a: 214–217 , figs 9–11. Vinogradov 1964: 125–126. Vinogradov et al. 1982: 107–109, figs 42, 43.

Type material. The holotype is in the ZMMU (Mb–1060) as detailed above.

Material examined. North Atlantic: Female ( ZMUC); Caribbean Sea [17°54’N 64°54’W]; Dana Stn. 1186 III , 3000 mw, 30 Nov. 1921 . South Pacific : Two males, two females ( ZMUC CRU-9935); west of Galapagos Is. [00°18’S 99°07’W]; Dana Stn. 3558 II, 3000 mw, 18 Sept. 1928 . Female ( ZMUC); N. of Tahiti [14°01’S 147°51.5’W]; Dana Stn. 3570 II, 3000 mw. 7 Oct. 1928 . Female ( ZMUC); N. of New Zealand [25°47’S 172°24’E]; Dana Stn. 3621 III, 3000 mw, 8 Dec. 1928 .

Diagnosis. Body length of females up to 8.0 mm, of males up to 6.0 mm or slightly more. Antennae 1; peduncular articles and callynophore relatively broader and longer in males; terminal article elongate, slightly longer than preceding article in males, slightly shorter in females. Antennae 2 slightly shorter than A1 for females, about 0.8x A1 for males; antennal gland grossly inflated, slightly deeper than long, about as long as following articles combined. Gnathopod 1; basis slightly shorter than remaining articles combined; dactylus slightly narrowed, length about half propodus. Gnathopod 2: length about 1.4x G1; basis marginally longer than remaining articles combined (excluding dactylus); dactylus length about 0.4x propodus. Pereopods 3 & 4 similar in structure but P4 is slightly longer; both longer and stronger than any other pereopoda. Pereopod 4; basis length about twice merus; carpus length twice merus; propodus length 1.4x carpus; dactylus length about one third propodus. Pereopod 5 strongly subchelate with propodus and dactylus rotated at right angles to body; length about 0.6x P4; basis length 1.7x merus; carpus length about 0.8x merus; propodus length about 1.5x carpus, relatively broad forming subchela with dactylus, anterodistal margin with several pairs of short, strong setae; dactylus curved, slightly longer than width of propodus. Pereopod 6 slightly longer than P5; basis length about twice merus; carpus marginally longer than merus; propodus length almost twice carpus; dactylus length 0.4x propodus. Pereopod 7; length 0.8x P6; basis length 2.5x merus; carpus length 1.4x merus; propodus length about 1.7x carpus; dactylus length slightly less than half propodus. Peduncle and rami of uropoda relatively narrow, lanceolate; margins of rami denticulate. Telson triangular, rounded, length about half peduncle of U3.

Colour of unfixed specimens is cherry-red ( Vinogradov 1960a).

Remarks. This is a distinctive but relatively rare species with only three previous records of specimens collected. It is similar to Microphasma agassizi differing mainly in the structure of pereopods 3–5. The current material examined comprises two males and five females. This is the first record of males

Distribution. Vinogradov et al. (1982) record this species from the tropical regions of the Pacific and Indian Oceans near the Philippines ( Vinogradov 1964), New Hebrides ( Vinogradov 1960a) and Japanese deep-water trenches (presumably a new record). It is here recorded from the North Atlantic (Caribbean Sea) for the first time together with additional records from the South Pacific. According to Vinogradov et al. (1982) it has been found in catches of 500–2000 m and in catches from depths of 1700 and more to the surface. The Dana specimens were all caught with 3000 mw.