Histioteuthis pacifica (Voss 1962)

Histioteuthis celetaria pacifica (G. Voss, 1962)

DESCRIPTION.—Female size at maturity not known (largest available specimen, 234 mm ML from 17°S, 119°E (TINRO, uncat.), is immature); male known to mature at 60–> 280 mm ML (largest known specimen from 31°N, 129°E, TINRO, uncat.); arms about 100%–125% ML; tentacular club with suckers on manus closely arranged in 6 rows, suckers of median 3 rows moderately enlarged with increased degree of enlargement from dorsal to ventral-most rows, diameter of largest median suckers 1 times ventral marginals (Figure 10f); asymmetrically broadened denticulate collar usually present on suckers of 2 ventral marginal rows; spermatophore short (SpL 1.3–2.0 mm; 1.7%–3.4% ML; 4 specimens, 65–82 mm ML from Philippines and northwestern Australia); sperm mass of medium length (21%–25% SpL), cement body and ejaculatory apparatus moderately long (35%–40% SpL); ejaculatory apparatus with single longitudinal loop of inner tube; ejaculatory-apparatus/cement-body connective complex well developed; mature egg not known; in mature female, presence of long, narrow, black, terminal photophore on arms I–III not known; in mature male, long, terminal photophore present but extent of development not known because of poor condition of ends of arms; gladius with anterior shoulders of vanes broadly rounded (Figure 10e); radula with stout rachidian; first, second, and third laterals of increasing length; marginal plates weak.

ORIGINAL REFERENCE.—Voss, 1962:174; original illustration, Voss, 1963, fig. 26.

TYPE LOCALITY.—Indo-West Pacific, off Dammi Island, Sulu Archipeligo, Philippines; 5°50′N, 120°31′E, 432 m.

DEPOSITION OF TYPES.—Holotype: USNM 575453, female, 74 mm ML, R/V Albatross sta D5564, 21 Sep 1909.

Paratypes (5 specimens): UMML 31.1339, USNM 575454, USNM 575455, USNM 575457 (2 specimens).

DISTRIBUTION.—Recently reported specimens (Nesis, 1977; Young, 1978; Toll, 1982; Lu and Phillips, 1985) and a considerable number of unreported ones found in the collections of various institutes (for list, see text preceding description of H. celetaria, above) show the distribution of H. c. pacifica to be largely associated with tropical or equatorial waters of the Indian and Pacific oceans (Figure 11). In the Indian Ocean, the subspecies is widely distributed in equatorial waters between 8°N and 10°S and extends into western peripheral waters of the southern gyre to 35°S. Of the seven species of histioteuthids (listed in decreasing order of numbers taken: H. celetaria pacifica, miranda, bonnellii and meleagroteuthis (equal number), atlantica, and hoylei and corona ?subsp. (equal number)) captured between 12°S and 34°S, 35°E and 54°E in the southwestern Indian Ocean during the 1988/1989 cruise of the R/V Vityaz, H. c. pacifica was found to be the most common one between latitudes 8°S and 26°S. Southward to 34°S, it was replaced by miranda as the dominant form (K. Nesis, unpublished data).

Histioteuthis celetaria pacifica occurs throughout most of the Indo-West Pacific and was taken in large numbers along the northwest shelf and slope of Australia during a recent resource survey of that area (Wadley, 1990; S. Slack-Smith, unpublished data, specimens examined (NV)). The subspecies ranges across the Pacific in equatorial waters to the Americas, where it has been collected from 4°S northward into the southern transitional waters of the California Current to 28°N. It also occurs in peripheral central waters around and north of the Hawaiiian Islands to 30°N. It is not known from the Peru-Chile Current or from southern subtropical waters. Although some specimens have been taken from open ocean, most have come from on or near continental and island slopes and submarine rises.

Data from open-net captures and the few available opening-closing-net captures (Young, 1978) show early juveniles to 15 mm ML to be present in the upper 200 m. A daytime opening-closing-net capture of a 10 mm ML specimen at 550 m off Hawaii shows the vertical range of this size group to extend into deeper waters. Older juveniles occur over a broad vertical range extending from deep water (possibly to 1000 m) to about 200 m at night and 400 m during the day. Subadults and adult males have been found day and night in the midwater and near shelf and slope bottoms between about 250–1000 m, with the majority taken deeper than 350 m. An analysis by one of us (KN) of the catch data for 47 specimens (mostly adult males, subadults, and large juveniles) recently taken in eight demersal-trawl hauls by the R/V Vityaz from Socotra Island to Mozambique in the western Indian Ocean shows that 34 specimens were caught while fishing depths of 364–500 m, 11 from depths of 501–750 m, and two from 751–1000 m. The largest (147 mm ML) of the 14 mature males taken and the largest female, a near-mature specimen of 146 mm ML, came from the deepest haul at 980–1000 m. An earlier, unpublished French study of the cephalopods from the same approximate area off Madagascar, between 12°S and 24°S, 43°E and 49°E, similarly showed the subspecies to be abundant and to be the most common histioteuthid taken. The collection of 29 mostly adult males (to 110 mm ML), subadults, and large juveniles were caught with midwater nets during the day at fishing depths largely between 450 m and 720 m (P. Rancurel, unpublished data; part of histioteuthid collection examined (by NV)). The 38 specimens of H. c. pacifica, representing the same growth stages as above (with adult males to 110 mm ML), contained in the earlier mentioned collections from off northwestern Australia were taken in trawls from off soft bottom between 400 m and 600 m during both day and night.