“Bathypurpurata profunda gen. et sp. nov.
Material examined Holotype. ANT XIV Sta. 40, 1 mature female, 23 mm DML U.S. National Museum of Natural History (USNM) cat no. 1020572.
Description External (Figures 1–2). Small dark incirrate octopod with numerous uniserial suckers on thin, rather long arms (about 2.5 X ML) and with very shallow web. Arms II>III>I=IV. Head narrower than mantle. Large eyes appear to be oriented postero-dorsally. Color when freshly collected purple dorsally, ventrally, and orally, but pigment leached rapidly into formalin fixative. Skin badly eroded ventrally but very small papillae on dorsal mantle. Ventral mantle and funnel damaged. Internal (Figure 2). Ink sac absent. Funnel organ W-shaped. Ovary swollen, filling posterior mantle cavity, containing ca 8–10 eggs of 4 × 3 mm. Proximal oviducts very short, barely extending beyond common junction with ovary. Oviducal glands ca 3.5 × 3.0 mm. Distal oviducts swollen, about equal in size to oviducal glands, each with nipple-like terminal papilla. Digestive tract not dissected. Dorsal mantle cavity heavily pigmented. Posterior salivary glands comparatively huge (each 9 X 8 mm; 45% ML).
Distribution Collected in a large bottom trawl at 61º02’S 054º49’W, 509–565 m depth. NE of Elephant Island, South Shetland Islands, off Antarctic Peninsula.
Etymology The genus and species names refer to the deep purple color of the animal when first collected and the depth at which it was found.
Table 1. Counts and measurements (mm) for Bathypurpurata profunda gen. et sp. nov.and Graneledone antarctica.
Character
B. profunda
G. antarctica
Sex
female
female
Maturity stage
5
4
Total length
80
420
Dorsal mantle length
23
104
Ventral mantle length
21
81
Mantle width
18
113
Head width
12
68
Eye diameter
4
28
Pallial aperture width
9
69
Full funnel length
6
41
Free funnel length
2
22
Deepest web depth
11
95
Arm width
5
20
Left dorsal arm length
53
310
Left dorsolateral arm length
57
310
Left ventrolateral arm length
56
280
Left ventral arm length
53
240
Right dorsal arm length
52
310
Right dorsolateral arm length
57
310
Right ventrolateral arm length
53
280
Right ventral arm length
53
240
Left ventrolateral arm sucker count
42
58
Longest arm sucker count
43
58
Sucker diameter
1
6
Inner gill lamellae count
5
6
Outer gill lamellae count
4
6
Comments The holotype, and only known specimen, was in fairly good condition when it was first collected (Fig. 1), but it was damaged by collection of a tissue sample and it further deteriorated rapidly when fixed in formalin/ seawater. This very unusual octopod can be distinguished from other genera with uniserial suckers because of the small size at which it matures and because of the comparatively huge posterior salivary glands and shallow web. Although pygmy-sized octopods with large salivary glands are well known from shallow, warm-water environments, these are unexpected characters in a deep-water polar species. The lack of an ink sac and small number of gill lamellae are, however, common among deep-sea species (Voss, 1988). Other genera of deep-water octopods with uniserial suckers but lacking an ink sac include Graneledone, “Bentheledone” (see discussion below), and Thaumeledone. Graneledone is characterized by prominent cartilaginous tubercles on the dorsal mantle and head, lacking in the current specimen. “Bentheledone”, which currently is poorly defined and in need of systematic revision, and Thaumeledone both have very deep webs. None of these genera have huge posterior salivary glands. We therefore consider this unique specimen to be the type species of a previously unknown genus. In shallow-water octopods, very large posterior salivary glands are characteristic of small species that use venom to overcome large prey. It therefore seems likely that the present species occupies a feeding niche very different from those of most deep-sea octopods, which generally have small to very small posterior salivary glands.”
(Vecchione et al., 2005: 110-112)
Bathypurpurata is a genus of incirrate octopus in the family Megaleledonidae from the Antarctic Ocean. The genus has only one species, Bathypurpurata profunda, a small purple octopus which lacks an ink sac and has a single row of suckers and a very large salivary gland. It was described in 2005 from a type specimen caught between the Antarctic Peninsula and the South Shetland Islands.[2]
Bathypurpurata is a genus of incirrate octopus in the family Megaleledonidae from the Antarctic Ocean. The genus has only one species, Bathypurpurata profunda, a small purple octopus which lacks an ink sac and has a single row of suckers and a very large salivary gland. It was described in 2005 from a type specimen caught between the Antarctic Peninsula and the South Shetland Islands.
