Liocranchia
Pfeffer, 1884
Page authors: K. Bolstad, R. Young & K. Mangold (1922-2003)
These moderate-sized squids reach a maximum size of about 250 mm (Nesis, 1983/1987). They are cosmopolitan in tropical and subtropical waters although Young (1995) suggested that L. reinhardti may be a mesopelagic boundary species (i.e., associated with land masses). In Hawaiian waters L. reinhardti is a vertical migrator while L. valdiviae is a deep-living non-migrator (Young, 1978).
Brief diagnosis:
A cranchiin with two strips of diverging cartilaginous tubercules (together forming a V shape--see image below) originating at each funnel-mantle fusion.
Key morphological features (from Voss 1980):
- Tentacles: Suckers and pads in two series on distal 2/3 of tentacle stalk
- Head: Eyes sessile in paralarvae
- Funnel: With funnel valve; funnel organ with very large ventral pads
- Mantle: With distinct V-shaped series of cartilaginous strips on ventral mantle, originating at mantle-funnel fusion sites and diverging posteriorly (visible on live animal at 0:33 here)
- Fins: United posterior to gladius (nearly circular in combined outline)
- Photophores: Number of oval photophores on each eye varies with species (4 or 14; see table below); mature or nearly mature females develop photophores on tips of Arms III
Above: Ventral view of Liocranchia reinhardti showing the V-shaped ventral cartilaginous strips at the funnel-mantle fusion. From Voss (1980).
| Cartilaginous tubercles present along dorsal midline of mantle | Number of photophores on eyeball | |
| L. reinhardti | Yes | 14 |
| L. valdiviae | No | 4 |
Live animal
Video footage of Liocranchia has been collected on several recent Schmidt Ocean Institute dives:
- Here (timestamp 2:57:40) Dhugal Lindsay explains some of the squid's features during an observation in Australian waters (a great example of the transparency that inspired the common name 'glass squids').
- Here a much more opaque (probably older) individual is observed in the Galapagos hydrothermal vent field.
- Most of the information on this page has been migrated and updated from the original Liocranchia page on the Tree of Life web project.
- Nesis, K.N. 1983/1987. Abridged key to the cephalopod mollusks of the world’s oceans. Light and Food Industry Publishing House, Moscow, 358pp. [In Russian]. Cephalopods of the World; Squids, Cuttlefishes, Octopuses, and Allies. T.F.H. Publications, Inc., Neptune City, NJ, USA, 351 pp.
- Voss, N. A. 1980. A generic revision of the Cranchiidae (Cephalopoda; Oegopsida). Bulletin of Marine Science 30: 365-412.
- Young, R. E. 1978. Vertical distribution and photosensitive vesicles of pelagic cephalopods from Hawaiian waters. Fisheries Bulletin 76: 583-615.
- Young, R. E. 1995. Aspects of the natural history of pelagic cephalopods of the Hawaiian mesopelagic-boundary region. Pacific Science 49: 143-155.