Lanceola longidactyla Vinogradov

Zeidler, Wolfgang, 2009, A review of the hyperiidean amphipod superfamily Lanceoloidea Bowman & Gruner, 1973 (Crustacea: Amphipoda: Hyperiidea), Zootaxa 2000, pp. 1-117 : 48-50

Lanceola longidactyla Vinogradov

( Fig. 15)

Lanceola longidactyla Vinogradov, 1964: 112 –114 , fig.3. Vinogradov et al. 1982: 72–73, fig. 19. Type material. This species was described from one female, 8.0 mm in length, from the Indian Ocean [19º09’S 63º 07’E], at 0–2400m depth. The unique holotype is in the ZMMU (Mb –14048) on microscope slides.

Material examined. One immature female 7.4 mm ( ZMUC); Tasman Sea [33º33’S 154º04’E]; Dana Stn. 3663 II, 4000 mw, 23 Feb. 1929 .

Diagnosis. Only known from two, sexually immature, females with body length of 7.4 & 8.0 mm. Head without rostrum, eyes relatively small, reniform, without crystalline cones. Antennae 1 as long as head and first 1.5 pereonites combined; terminal article elongate, twice length preceding article. Antennae 2 length 1.5x A1, slightly longer than head and first two pereonites combined; fourth peduncular article with small lobe overlapping following article posteriorly; first flagellar article swollen, oval-shaped. Gnathopoda with relatively long dactyls, that of G1 0.7x propodus. Pereopod 3 similar to, but slightly shorter than P4; basis length 2.5x merus; carpus twice as long as merus; propodus slightly longer or equal in length (P4) to carpus; dactylus length about 0.8x propodus. Pereopods 5–7 with retractile, fully hooded dactyls; the “hood” with groove for dactyl resulting in forked appearance from anterior aspect. Pereopod 5; length about 0.8x P4; basis length twice merus; carpus length 1.7x merus; propodus length 1.4x carpus. Pereopod 6 slightly shorter than pereon, slightly longer than P5 but only about 0.8x length P4; basis length 1.7x merus; carpus length 1.4x merus; propodus length 1.5x carpus. Pereopod 7; length 0.7x P6; basis length about 2.5x merus; carpus length 1.7x merus or longer; propodus length about 1.5x carpus. Peduncle of U1 does not exceed limit of peduncle of U2. Peduncles and rami of uropod relatively narrow. Uropod 3; peduncle width 0.4x length. Telson rounded; length 0.6x peduncle of U3.

Colour of living specimens not recorded.

Remarks. This is only the second specimen of this species on record. It is readily distinguished by the relatively long dactyls of the gnathopoda, especially the second, by the extraordinarily long dactyls of pereopods 3 & 4 and by the inflated first flagellar article of the second antennae. Other distinguishing characters are the relatively short merus of pereopods 3–7, the relatively short telson, as in L. loveni ; and the forked hood of the dactyls of pereopods 5–7 similar to but found in L. galatheae sp. nov. This is also one of the few species that have pereopod 6 shorter than pereopod 4. In L. clausi the relative length of pereopod 6 varies from slightly shorter to slightly longer than pereopod 4 and only in L. chelifera Vinogradov, 1970 is pereopod 6 clearly shorter than pereopod 4 as in L. longidactyla .

Distribution. Only known from two immature female specimens; the unique type from the Indian Ocean, East of Mauritius [19º09’S 63º07’E]; from a haul 0–2700 m and this record from the south-west Pacific Ocean, Tasman Sea [33º33’S 154º04’E]; from a haul with 4000 mw. The latter is a new record for Australian waters.