Characters: Colonies are a network of anastomosing branches, either compacted or open, and up to 5 metres across in lagoons with soft substrates. Branches are triangular in section. Valleys are short and shallow with thick columellae and septa which, except near branch tips, are fused into one solid structure. Tentacles may be extended during the day. There is little or no development of an encrusting base and no development of laminae.
Colour: Pale yellow or cream.
Similar Species: Branch tips may resemble those of Hydnophora and Merulina but are readily distinguished from both by their triangular section, shallow valleys and highly fused skeletal elements. Merulina also differs in having laminae and encrusting bases.
Habitat: Reef environments protected from strong wave action.
Abundance: Usually uncommon.
Taxonomic Note: The genus Paraclavarina is considered a synonym of Merulina by Huang, Benzoni, Fukami et al. (2014) on the basis that “there are no diagnosable morphological differences” between them. These genera are, however, distinctive in both gross and fine morphological structure. The three species of Merulina are similar, usually with laminar bases and irregular contorted upgrowths. Paraclavarina triangularis consists entirely of regular fused branches which are triangular in section. It does not closely resemble any other species.
Taxonomic References: Veron and Pichon (1980); Veron (2000a); Huang, Benzoni, Fukami et al. (2014); Huang, Benzoni, Arrigoni et al. (2014);
Identification Guides: Veron (1986a);
