Lanceola intermedia Vinogradov

Zeidler, Wolfgang, 2009, A review of the hyperiidean amphipod superfamily Lanceoloidea Bowman & Gruner, 1973 (Crustacea: Amphipoda: Hyperiidea), Zootaxa 2000, pp. 1-117 : 46-48

Lanceola intermedia Vinogradov

( Fig. 14)

Lanceola intermedia Vinogradov, 1960a: 200–204 , fig. 2, 3b. Vinogradov 1964: 110. Vinogradov et al. 1982: 56, fig. 6b, 7. Vinogradov 1993: 43 (table). Shih & Chen 1995: 34–35, fig.17.

Type material. This species was described from five, sexually immature specimens, 9–15 mm in length, from the tropical Pacific. A specimen of 12 mm length was used for the description and illustration. One syntype is in the ZMMU (Mb–1045).

Material examined. North-East Atlantic: Juvenile ( ZMUC); W. of Senegal [15°31’N 18°05’W]; Dana Stn. 4006 III, 300 mw, 13 Mar. 1930 . South-East Atlantic : Juvenile ( ZMUC); off South Africa [30°15’S 13°15’E]; Dana Stn. 3978 XI, 1000 mw, 13 Feb. 1930 . North-East Pacific : Female ( ZMUC); Gulf of Panama [06°40’N 80°47’W]; Dana Stn. 1206 , 4500 mw, 14 Jan. 1922 . North-West Pacific : Male, juvenile ( ZMUC); E. of Taiwan [24°15’N 122°00’E]; Dana Stns. 3728 IV & XIX, 100 mw, 12 Jun. 1929 . Juvenile ( ZMUC); N.E. of Halmehera [03°50’N 131°42’E]; Dana Stn. 3746 II, 800 mw, 9 Jul. 1929 . South-West Pacific : Female ( ZMUC); N. of New Zealand [30°08’S 176°50’E]; Dana Stn. 3627 III, 3000 mw, 14 Dec. 1928 . Central South Pacific : Male ( ZMUC CRU-9923); N. of Tahiti [14°01’S 147°51.5’W]; Dana Stn. 3570 IX, 50 mw, 7 Oct. 1928 . Juvenile ( ZMUC); near Samoa [11°00’S 172°37’W]; Dana Stn. 3587 XIII, 4000 mw, 2 Nov. 1928 . Female ( ZMUC); W. of Samoa [13°56’S 172°30’W]; Dana Stn. 3590 IV, 50 mw, 7 Nov. 1928 . East Indian : Female ( ZMUC); S. of Sumatra [02°15’S 98°55.5’E]; Dana Stn. 3817 III, 300 mw, 11 Sept. 1929 . Male ( ZMUC); S. of Sumatra [04°45.5’S 98°28’E]; Dana Stn. 3856 IV, 100 mw, 17 Oct. 1929 . Male ( ZMUC); S. of Sri Lanka [06°36’N 79°06’E]; Dana Stn. 3913 IV, 100 mw, 1 Dec. 1929 . West Indian : Female ( ZMUC); S. of Seychelles [08º27’S 50°54’E]; Dana Stn. 3926 I, 600 mw, 16 Dec. 1929 . Male , juvenile ( ZMUC); N. of Madagascar [10°55’S 50°15’E]; Dana Stn. 3927 IV, 100 mw, 17 Dec. 1929 . Male , four females, juvenile ( ZMUC); N. of Madagascar [12°11’S 50°18’E]; Dana Stns 3929 I–IV & VII, 100–600 mw, 17 Dec. 1929 . Male , juvenile ( ZMUC); N. of Madagascar [11°35’S 49°45’E]; Dana Stns 3932 II & III, 500 & 400 mw, 20 Dec. 1929 . Male , female, two juveniles ( ZMUC); N. of Madagascar [11°24’S 50°05’E]; Dana Stn. 3934, 400 mw, 20 Dec. 1929 . Two juveniles, ( ZMUC); Mozambique Channel [18°30’S 42°18’E]; Dana Stn. 3955 V, 50 mw, 9 Jan. 1930 . Female ( ZMUC); Mozambique Channel [21°13’S 42°26’E]; Dana Stn. 3956 V, 50 mw, 10 Jan. 1930 .

Diagnosis. Sexually mature specimens not known; largest specimen examined/recorded 17 mm. Head with short, rounded, slightly bent, overhanging rostrum. Eyes relatively large, composed of paired crystalline cones. Antennae 1 as long as head and first 1.5 pereonites combined; terminal article barely longer than preceding one, triangular, somewhat truncated dorsally. Antennae 2 length about twice A1, as long as head and first 2.5 pereonites combined; fourth peduncular article with long rounded lobe overlapping following article medially for, more or less, proximal half. Pereopod 3 similar to, but slightly shorter than P4; basis length 1.2x merus; carpus length 0.6x merus; propodus length 0.8x carpus; dactylus curved, very short, length slightly more than 0.1x propodus. Pereopod 5–7, with retractile, fully hooded dactyls. Pereopod 5 slightly longer than P4; basis length 1.4x merus; merus length 1.8x carpus; propodus slightly longer or subequal in length to carpus. Pereopod 6 slightly shorter than pereon, about 1.2x length P5; basis slightly longer than merus; carpus length about 0.7x merus; propodus length about 1.2x carpus. Pereopod 7; length 0.7x P6; basis length 1.6x merus; carpus length 0.7x merus; propodus slightly longer than carpus. Peduncle of U1 does not exceed limit of peduncle of U2. Peduncle and inner ramus of U3 broad; peduncle width 0.5x length. Telson rounded clearly longer than peduncle of U3.

Colour of living specimens not recorded.

Remarks. This species is readily distinguished by the long lobe of the fourth peduncular article of the second antennae. Other species with a similar lobe are L. pacifica , L. longidactyla and L. galatheae sp. nov. but in these species the lobe is much shorter than half of the following article. Other diagnostic characters of L. intermedia are the truncate terminal article of the first antennae, the rounded almost “fleshy” rostrum, the eyes with crystalline cones, the relative lengths of pereopods 5–7 and the long telson. It most closely resembles L. sayana and L. galatheae sp. nov. but is readily distinguished from both by the shape of the rostrum and the terminal article of the first antennae, and by the relative lengths of pereopods 5–7.

Prior to this study only ten specimens of this species had been recorded in the literature. However, the record of three females from the South China Sea by Shih and Chen (1995) is considered doubtful because their description and figure attributed to L. intermedia is more consistent with L. pacifica than L. intermedia . In particular the head is without the characteristic rounded rostrum, pereopod 6 is relatively longer and pereopod 7 is relatively shorter. Also, in their figure, they illustrate the merus of pereopods 3 & 4 with the anterodistal corner produced and the merus of pereopod 5 with the posterodistal corner produced; characters diagnostic of L. pacifica . It seems likely that an error in identification was made based on the structure of the second antennae, in which the fourth article of the peduncle is produced into a rounded lobe overlapping the following article; a diagnostic character of L. intermedia . The fact that this character is also found in L. pacifica has not been recorded in the literature previously but, although variable in length, is always much shorter than half of the following article. Also, Shih and Chen would not have known that the eyes of L. intermedia consist of paired crystalline cones, those of L. pacifica being reniform, without crystalline cones; a character which readily distinguishes the two species.

The Dana collections include 31 specimens of this species from the three major oceans of the world. It is recorded from the Atlantic Ocean for the first time.

Distribution. This seems to be a relatively rare species. Previous records are from the tropical Pacific ( Vinogradov 1960a) and the Indian Ocean, from the Arabian Sea ( Vinogradov 1964) and Walters Shoal ( Vinogradov 1993). The Dana found it in the tropical waters of the Atlantic, Pacific and Indian Oceans. The Dana collections indicate that it is relatively rare in the Atlantic and may be more common in the Indian than the Pacific Ocean. It seems to prefer surface waters but has been recorded from 1000–2000 m ( Vinogradov 1960a). The Dana collected most specimens in hauls with less than 500 mw, with the deepest haul with 4500 mw.