Description of two new species of Paraonidae (Annelida) from the Gulf of Thailand, Western Pacific

Two new species of Aricidea Webster, 1879 (Paraonidae), Aricidea (Acmira) anusakdii sp. nov. and Aricidea (Aricidea) thammapinanae sp. nov. were collected from 10–26.5 m depth, in shallow soft bottoms with mud mixed with sand and shell substrates at Songkhla Sea, the Gulf of Thailand between 2011–2018. Aricidea (Acmira) anusakdii sp. nov. is clearly distinguished from other species of the subgenus Acmira by having a rounded bilobed prostomium divided by a slight notch on the anterior margin; red pigments on the subdistal to the tip of each branchia (new character); two prebranchial chaetigers; 48–68 pairs of branchiae; and modified neurochaetae as strong curved spines with blunt shafts surrounded by pubescence from chaetigers 19–44. On the other hand, Aricidea (Aricidea) thammapinanae sp. nov. can be separated from other members of the subgenus Aricidea by the presence of a biarticulated median antenna; distinctive notopodial lobes as broad triangular with short distal protuberances on ...