Type : Muséum national d’Historie naturelle, Paris, Cat. nº AF-406; BT Sta. 452; “devant labo., Ilo-Ilo, seagrass bed”. Paratype: Cat. nº AF-407; BT Sta. 419; Récif de Songoritelo”; Cat. nº AF-408; BT Sta. 136; “Grand Récif”, Tuléar.
This small worm may be misidentified as a Nephasoma species because the anal shield is overlooked or absent, and the smaller angle between the origin of the introvert and the anterior trunk. The introvert is up to 4 times the trunk length and apparently does not bear hooks and tentacles. Aspidosiphon thomassini has been collected in intertidal coral sand only in Madagascar and French Polynesia.
(From Cutler & Cutler 1979, Cutler 1994)
External anatomy
Introvert is 2 to 4 times as long as the trunk, and arises in an angle of 40º to 45º with the main trunk axis.
This species appears to have neither tentacles nor hooks.
The anal shield is often poorly defined and variable. In those specimens in which it is developed, the anal shield is composed of small, scattered units that give the appearance of rough skin.
The caudal shield is absent.
Internal anatomy
The longitudinal muscle layer of the trunk wall is continuous.
Intestine attached posteriorly by spindle muscle.
Rectal caecum is absent.
Nephridia are about half of the trunk length, attached to the trunk wall almost their entire length, open slightly posteriorly to the anus.
A pair of retractor muscles, fused for most of their length, originates near but not at the posterior end of the trunk.
This species is a small worm measuring between 1.5 to 7 mm long (Cutler & Cutler 1979).
(From Cutler & Cutler 1979, Cutler 1994)
Reported only in Madagascar and French Polynesia.
(From Cutler & Cutler 1979, Cutler 1994)
Intertidal coral sand.
