Gastropods from the Burdwood Bank (southwestern Atlantic): an overview of species diversity Author Luca, Javier Di Author Zelaya, Diego G. text Zootaxa 2019 2019-01-10 4544 1 41 78 journal article 27685 10.11646/zootaxa.4544.1.2 2f89f82f-be57-45b4-ad3c-ed72a7647551 1175-5326 2618137 211842AA-6C98-425B-9377-1AF0DC78C893 Thesbia michaelseni (Strebel, 1905) Fig. 4K Daphnella ( Thesbia ) michaelseni Strebel, 1905b : 590 , pl. 22, figs. 20, 20a–c Thesbia michaelseni — Castellanos & Landoni, 1993 : 15 Examined material. 1 an. and 2 sh. (MACN-In 40695); 1 syntype (ZMH unnumbered). Description. Shell height to 4.6 mm (up to 10.2 mm according to Strebel 1905b ); fusiform, delicate. Protoconch large, translucent, of about 1.75 slightly convex whorls; transition to teleoconch poorly defined. Teleoconch of up to 3 whorls, slightly convex in outline; last whorl comprising about 80% of total shell height. Suture impressed. Surface whitish, somewhat translucent; sculptured with very weak spiral threads, 9 to 12 on the spire whorls, and about 30 on the last whorl; well-marked growth lines are evident along all teleoconch whorls. Aperture ovate, interior white; columellar callus narrow, slightly expanded on the base; siphonal canal short, somewhat oblique, wide.