Protula tubularia is a genus of marine polychaete worms.
They are listed under the family of Serpulidae, a family of tube building worms. The genus has two subgenera; one being Protula Hydroides, the other Protula Protulopsis. The genus Serpula was first described in 1767 by Carl Linnaeus. It was said the worm lives in a tube into which it can retract.
The Protula tubularia has a small, elongated, segmented body that tapers towards the posterior. It grows up to a length of 0.3 – 0.5 cm.
This species forms a white, calcareous tube showing no distinctive growth marks in which it lives.
The head is reduced, bearing two gill lobes with 20 – 45 white or pinkish, slightly spiralled in shape tentacles that are pinnate in two rows and marked with paired red blotches and numerous eyespots.
A fine collar that bears finely toothed chaetae surrounds the head, extending downward to a distinctive, large, lobed membrane either side of the thorax.
Chaetae are present on all segments except the first. They are very much like a bristle and are made of chitin. Chaetae are pale golden, long and slender which display narrow wings in the thoracic region of the head. The chaetae in the posterior region do not display wings.
The body itself is divided into a head, with a green, short anterior region of eight segments and a much longer reddish-orange, posterior region of up to 90 – 120 segments.
The Protula tubularia is often found to be solitary. It lacks the distinctive stalked appearance that characterizes the Serpula vermicularis. It is commonly found on rocks and boulders in the shallows and down to very deep depths. They are classed as filter feeds, filtering their prey out of the water as it passes by.
The Protula tubularia reproduces throughout the months of June, August and September.
Photo by Janet Bulmer at DiveSMART Gozo
Dive site encounter: Reqqa Point