Perkinsiana milae Giangrande & Gambi, 1997

The species has a variable number of thoracic chaetigers, ranging from 3 to 8, of which 6 is the most common. The number of thoracic chaetigers is not correlated to worm size, while the length of the crown is well correlated to total body length. Total length up to 32 mm of which 8 mm is the branchial crown. Maximum body width 1 mm. Thoracic and abdominal chaetigers almost as long as wide. Each half of branchial crown involuted ventrally with about 10 radioles in each lobe. Palmate membrane and radiolar flanges absent; ventral radioles shorter than dorsal ones. End of radioles with tapering terminal filament. Radiolar skeleton angular in cross section. Radiolar appendages of dorsal lips as long as two thoracic chaetigers, pinnular appendage small. Ventral lips present, parallel lamellae present. Collar very oblique, with a wide gap mid-dorsally, and with two high rounded lappets ventrally. Dorsolateral margins not covering juntion between thorax and crown base. Thoracic tori long, indenting the thoracic shields, each with 40-45 uncini, handle length about twice distance between crest and breast, companion chaetae with a flat and very long tapered blade at right-angles; 4-5 superior thoracic notochaetae and 10-15 inferior paleate chaetae with long tips. Abdominal uncini similar to thoracic uncini, abdominal chaetae geniculate broadly hooded. Tube, translucent, encrusted with fine sand grains.

Common name: fan worm