Paralarva

Octopus paralarva

Squid paralarva: Psychroteuthis glacialis

Grimalditeuthis bonplandi paralarva

Grimalditeuthis bonplandi adult

Paralarvae (singular: paralarva) are young cephalopods in the planktonic stages between hatchling and subadult. This stage differs from the larval stage of animals that undergo true metamorphosis.^[1] Paralarvae have been observed only in members of the orders Octopoda and Teuthida.^[2]

The term was first introduced by Richard E. Young and Robert F. Harman in 1988.^[2]

Chtenopteryx sicula paralarvae. Left: Two very young paralarvae. The circular tentacular clubs bear approximately 20 irregularly arranged suckers. Two chromatophores are present on each side of the mantle. Centre: Ventral, dorsal and side views of a more advanced paralarva. An equatorial circulet of seven large yellow-brown chromatophores is present on the mantle. Posteriorly the expanded vanes of the gladius are visible in the dorsal view. Right: Ventral and dorsal views of a very advanced paralarva.

References

↑ "Paralarvae". Larval Images: Larval forms diverse and beautiful!.
1 2 Richard Edward Young & Robert F. Harman (1988). ""Larva", "Paralarva", and "Subadult" in Cephalopod Terminology". Malacologia 29 (1): 201–207. Retrieved August 13, 2011.

Cephalopod anatomy

Shell

Shell types	External shells: Ammonoid shell Argonautid eggcase Nautiloid shell Orthocone Internal shells: Belemnoid guard Cirrate shell Cuttlebone Gladius (pen) Spirula shell Stylet

External features	Aperture Apex Callus Lirae Periostracum Sculpture Spire Sutures Umbilicus

Internal features	Body chamber Camerae Nacre Phragmocone Septa Siphuncle Whorls

Mantle

External anatomy	Funnel Dermal structures Fins (wings) Mantle locking-apparatus

Internal anatomy	Branchial hearts Ctenidia (gills) Hepatopancreas (digestive gland) Ink sac and ink Needham's sac Nephridia ("kidneys") Nidamental glands Osphradium Pericardial glands

Head and limbs

Brachial crown	Arms Hectocotylus Tentacles

Buccal region	Aptychus Beak Odontophore Radula Spadix and antispadix

Other parts	Eyes Statocysts

General

Chromatophores
Photophores
Nervous system
- Squid giant axon
- Squid giant synapse

Developmental stages: Spawn → Paralarva (Doratopsis stage) → Juvenile → Subadult → Adult • Egg fossils • Protoconch (embryonic shell)

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Paralarva

See also

References