Description:-

Fresh specimens pale reddish brown with numerous chromatophores on the dorsal side. On the ventral mantle chromatophores concentrated medially in the form of a definite longitudinal midventral line, conspicuous in males but very faint in females. Mantle slender, cylindrical and widest at the middle and tapers from the point of insertion of fins and ends in a blunt point. On the dorsal side, the anterior margin of the mantle produced in the middle to a pointed lobe. Fins narrow, rhombic, with anterior margin slightly convex and the posterior margin slightly concave in small specimens and almost straight in larger specimens. ). Head is comparatively small and short. Head width shorter than mantle width. Eyes large. Buccal membrane with 7 lappets, each lappet bearing 5–11 minute suckers. Funnel small, placed in a deep furrow beneath the head. Arms slender and short; arm formula III>II>IV>I or III>IV>II>I. Third pair of arms longer and stout. Left ventral arm of male hectocotylized for 40–45% of its length, suckers modified in to two rows of uniform, cone-shaped pointed fleshy papillae, bearing minute suckers on their tips; papillae on the ventral row slightly larger than those of dorsal row, 15–20 pairs of normal suckers present on proximal part. Arm suckers biserial, medium-sized, larger on arm II and III; chitinous sucker rings smooth or wavy proximally and 6–9 plate-like squared teeth distally. The lateral teeth slightly broader, but shorter than the distal teeth. Tentacles short and slender, moderately expanded club, club suckers quadriserial; two median rows of suckers larger than marginal rows. The largest club suckers bear 22–26 sharp curved conical teeth on the entire margin; they are largest on the distal margin, smaller and blunt teeth towards the proximal margin. Gladius very narrow and slender, with almost straight lateral margins along the vane.

Threats:-

Not recorded

Remark:-

: Silas et al. (1985) recorded U. sibogae for the first time from Indian waters. This species supports a major fishery along the southwest coast of India. Silas et al. (1985) studied biology of this species from Vizhinjam coast of Kerala.

Habitat:-

Semi pelagic, neritic species.

Synonyms:-

References:-

Silas, E. G. (Ed.) (1985). Cephalopod bionomics, fisheries and resources of the exclusive economic zone of India. Bull. Cent. Mar. Fish. Res. Inst., 37: 195pp.
Sreeja, V. (2013). Taxonomy and diversity of cephalopods (Mollusa: Cephalopoda) of Kerala coast. PhD Thesis submitted to University of Kerala, India.