Virulariidae Family of Sea Pens

One Sea Pen from the Virulariidae Family can be found in this website:

Elongate Sea Pen, Stylatula elongata. A reprsentative Sea Pen of the Virulariidae Family.

Sea Pens of the Virulariidae Family, the Slender Sea Pens, like hydroids, jellyfish and sea anemones are in the Phylum Cnidaria. This is indicative that they have radial symmetry, a hollow digestive cavity, and specialized stinging structures in tentacles surrounding the mouth. Their common name Sea Pen refers to their resemblance to the quill pens of antiquity. Sea Pens have been known since the ancient Romans, who called them “penna marina” (sea feather or sea pen) and also “mentula alata” (winged penis).

Sea Pens of the Virulariidae Family are in the Class Anthozoa, indicative that their polyps have a flower-like appearance. They are in the sub-class Octocorallia (also known as Alcyonaria). Octocorals are colonial organisms that have 8-fold radial symmetry. Their 8 tentacles are pinnate (having a feather-like appearance). Octocorals lack the hard calcium carbonate skeletons of Stony Corals and are often called Soft Corals. In place of a hard skeleton, they have tiny spine-like hard parts in their bodies called sclerites (or spicules) that give them some degree of support. Colonies may be branch-like, fan-like, bushy or encrusted. Octocorals include sea fans, sea rods, and sea whips.

Sea Pens of the Virulariidae Family are in the Order Pennatulacea.

Slender Sea Pens in the Virgulariidae Family have an elongated shape with bilateral symmetry and a pronounced quill. Their polyp leaves (lateral plumes) are often translucent. They are found from the intertidal zone to depths exceeding 1,200 m (3,936 feet) and can reach 60 cm (2 feet 0 inches) in length. The Slender Sea Pens are suspension feeders, using their tentacles to capture suspended plankton from the surrounding water. In turn they are preyed upon by nudibranchs and star fish. Sea Pens reproduce sexually (by external fertilization) and asexually by budding. Some species have life spans that exceed 100 years.

The Slender Sea Pens are found in all temperate, and tropical seas. There are fifty-three known species in the Virulariidae Family of which two are found along Mexico’s Pacific coast.