''Liocranchia'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

glass squid The family Cranchiidae comprises the approximately 60 species of glass squid, also known as cockatoo squid, bathyscaphoid squid, cranch squid, or simply cranchiids. The common name "glass squid" derives from the transparent bodies of most spe ...

from the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Cranchiidae The family Cranchiidae comprises the approximately 60 species of glass squid, also known as cockatoo squid, bathyscaphoid squid, cranch squid, or simply cranchiids. The common name "glass squid" derives from the transparent bodies of most spe ...

. They are moderate-sized with a long, spindle-shaped mantle which tapers to a point at the rear and they can attain mantle lengths of . The species in ''Liocranchia'' have a cosmopolitan distribution in tropical and subtropical oceans although it has been suggested that one species, '' Liocranchia reinhardti'' is associated with land masses. In seas off

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

waters, ''L. reinhardti'' undergoes vertical migrations while '' L. valdiviae'' occurs in deep water and is sedentary. They are eaten by many oceanic predator species.

Characteristics

''Liocranchia'' species are characterised by having two rows of

cartilage Cartilage is a resilient and smooth type of connective tissue. Semi-transparent and non-porous, it is usually covered by a tough and fibrous membrane called perichondrium. In tetrapods, it covers and protects the ends of long bones at the joints ...

nous tubercules starting at each funnel- mantle fusion which diverge from each other along their length, each funnel having a valve and a very large

ventral Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

pad. The

tentacles In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work main ...

have duckers and pads in two series on distal 2/3 of tentacle stalk. In the paralarvae the eyes are not mounted on a stalk. The fins merge posterior to

gladius ''Gladius'' () is a Latin word properly referring to the type of sword that was used by Ancient Rome, ancient Roman foot soldiers starting from the 3rd century BC and until the 3rd century AD. Linguistically, within Latin, the word also came t ...

and they are almost circular in their combined shape. There are a number of oval photophores on each eye and this varies with species 4 in ''L. valdiviae'' and 14 in ''L. reinhardti''. There are also photophores on the tips of arms III in adult or subadult females. The males bear suckers in 2 rows on the middle part of the hectocotylized right or left arm IV.

Species

The genus ''Liocranchia'' consists of two valid species and one questionable species: *'' Liocranchia gardineri'' * Robson, 1921 *'' Liocranchia reinhardti'' (Steenstrup, 1856) *'' Liocranchia valdiviae'' Chun, 1910 The species listed above with an asterisk (*) is a ''

taxon inquirendum In biological classification, a ''species inquirenda'' is a species of doubtful identity requiring further investigation. The use of the term in English-language biological literature dates back to at least the early nineteenth century. The ter ...

'' and needs further study to determine if it is a valid species or a synonym.

References

External links

Tree of Life web project: ''Liocranchia''
{{Taxonbar, from=Q3204831 Cranchiinae Bioluminescent molluscs