''Spirobranchus cariniferus'', commonly known as the blue tubeworm or spiny tubeworm, or by its Māori name ''toke pā'', is a species of tube-building

polychaete Polychaeta () is a paraphyletic class (biology), class of generally marine invertebrate, marine annelid worms, common name, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that ...

worm endemic to New Zealand. This species forms patchy, belt-like

colonies In modern parlance, a colony is a territory subject to a form of foreign rule. Though dominated by the foreign colonizers, colonies remain separate from the administration of the original country of the colonizers, the '' metropolitan state'' ...

of hard, white, triangular tubes, each containing a bright blue worm. These are cemented to the shaded side of rocks in the lower to mid-

tidal zone The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species of ...

. It may also inhabit hard objects such as dead shells and small stones. When submerged, it puts out a fan of dark-blue

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 ...

to feed, which it retracts during

low tide Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables can ...

. Individuals living in Dunedin's

Otago Harbour Otago Harbour is the natural harbour of Dunedin, New Zealand, consisting of a long, much-indented stretch of generally navigable water separating the Otago Peninsula from the mainland. They join at its southwest end, from the harbour mouth. It ...

are the only polychaetes known to host gregarine parasites. Little is known about their impact on the worms, but it is likely to be a negative one.

Description

Adult worms can grow to 40 mm long and 3 mm wide. The tube is hard, white, and triangular in cross-section with a ridge running along the top. This extends from above the tube opening to form a sharp protective spine. The operculum is a flat,

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an adje ...

plate. Its stalk is flat with prolonged wings. Its body is a yellow to orange colour towards the posterior and a bright blue at the anterior.

Radiole A radiole is a heavily ciliated feather-like tentacle found in highly organized clusters on the crowns of Canalipalpata. Canalipalpata is an order of sessile marine polychaete worms consisting of 31 families (including the Sabellidae, Serpulidae, ...

s are a bright to dark blue with some white bands.

Diet

The blue tubeworm is a surface

filter feeder Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ...

. It feeds on

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

and organic particles, which it filters from the water using its fan of

Distribution

It is found throughout

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

. Its tube layers can be up to 30 cm thick in the cooler climate of the

South Island The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman ...

References

{{taxonbar, from=Q2517079 Serpulidae Animals described in 1843