Fritillaria formica var. Langerhans Lohmann 1896: 28.
Fritillaria formica f. digitata: Lohmann & Bückmann 1926: 167.
Fritillaria (Acrocercus) formica f. digitata: Tokioka 1960: 355.
Fritillaria formica digitata: Fenaux 1993: 63, 70, 83; 1998: 303, 304. Aravena & Palma 2002: 320, Fig. 10A.
Material examined. Eleven specimens (MDAFWU 2020 /373–383), St.205, January 2020.
Description. Trunk 1–2 mm long and strongly bent upwards in the digestive nucleus region. Mouth with upper and lower lips; the median lobe of the upper lip short and provided anteriorly with two finger-shaped bulges. Spiracles are small and circular. The ciliated spiraclular rings do not contact the mid-ventral line. Axis of the alimentary tract longitudinal. The posterior margin of the oikoplastic layer is extended to the stomach. Testis is more or less conical with circular angles in mature specimens. The distal extremity of the tail acuminate.
Global distribution. The Antarctic Ocean, Atlantic Ocean, Indian Ocean, Pacific Ocean, the Mediterranean Sea and the Red Sea (Fenaux et al. 1998). Type locality: Madeira, NE Atlantic Ocean.