Hippothoa divaricata Smitt, 1868

Morphology: 

Hippothoa divaricata forms adnate runner-like colonies composed of delicate uniserial branches, closely adhering to the substrate. The species is typically small, glossy and pearly white in colour. Autozooids are slender and club-shaped, with a long narrow thread-like portion proximally (closest to the colony origin) and a dilated distal section. The slender proximal section is one-half to twice as long as the distal section.

Each autozooid gives rise to a maximum of four lateral buds (new autozooids), with up to two buds each side, spreading diagonally to give an “x” shape. Autozooids are typically 0.3 mm long.

Distribution: 

Hippothoa divaricata is widely distributed in the North Atlantic from Spitzbergen south to the Bay of Biscay and the Mediterranean. Records from outside this area are unreliable, owing to confusion with related species.

Habitat: 

The species is able to colonise stones and shells. It is mainly found in subtidal waters, but also rarely on the lower shore.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith