BIOTIC

BIOTIC Species Information for Virgularia mirabilis
All Taxonomy Biology Distribution Reproduction

Researched by	Jacqueline Hill & Emily Wilson	Data supplied by	MarLIN
Refereed by	This information is not refereed.
Taxonomy
Scientific name	Virgularia mirabilis	Common name	Slender sea pen
MCS Code	D618	Recent Synonyms	None

Phylum	Cnidaria	Subphylum
Superclass	Anthozoa	Class	Octocorallia
Subclass		Order	Pennatulacea
Suborder		Family	Virgulariidae
Genus	Virgularia	Species	mirabilis
Subspecies

Additional Information	As is the case for all octocorals, sea pens are actually colonies of polyps. What distinguishes sea pens is polyp dimorphism. One polyp grows very large and loses its tentacles, forming the central axis. The central axial polyp is divided into two regions: a lower peduncle or stalk, which never bears secondary polyps and functions as a burrowing organ, and an upper stem or rachis, from which numerous secondary polyps bud. Some of these secondary polyps, called autozooids, are typical feeding polyps. Others, the larger and fewer siphonozooids, serve as intakes for water, which circulates within the colony and helps keep it upright. The axial polyp contains a slender, unbranched, calcareous skeletal rod (axis). In this species the axis is round in section and often protrudes from the top of the colony. Virgularia mirabilis live upright with their stalks thrust into a mucus-lined burrow into which the whole colony can withdraw when disturbed.
Taxonomy References	Howson & Picton, 1997, Hayward & Ryland, 1995b, Hayward et al., 1996, Manuel, 1988,