Crispatotrochus rubescens (Moseley 1880)

Crispatotrochus rubescens (Moseley, 1881)

Cyathoceras rubescens Moseley, 1881:157, pl. 2: fig. 8a–c.—Marenzeller, 1888b:21–22.—Yabe and Eguchi, 1942b:117.—Cairns, 1984:15.

Cyathoceras diomedeae Vaughan, 1907:77–78, pl. 7: figs. 1, 2.

Cyathoceras diomedae [sic].—Yabe and Eguchi, 1942b:116–117, pl. 9: fig. 8.

Crispatotrochus rubescens.—Cairns, 1991a:15.

DESCRIPTION.—Corallum ceratoid, with a flared calice and a firmly attached pedicel about one-quarter diameter of calice. Illustrated specimen (Soyo Maru-33) 24.3 × 20.6 mm in calicular diameter and 30.4 mm in height, with a pedicel diameter of 6.6 mm. Costae ridged only near calice, otherwise consisting of broad, flat, finely granulated strips. Corallum white or reddish brown.

Septa hexamerally arranged in 5 cycles: S1–2>S3>S4>S5. S1–2 highly exsert (as much as 7 mm), and have sinuous, vertical inner edges that join the columella. S3 considerably less exsert (about 4 mm), but as much as 80% as wide as S1–2 and also have sinuous inner edges. S4–5 equally exsert (about 2.5 mm), the S4 about half size of S3 and the S5 about half size of S4. Fossa moderately deep, containing a crispate, fascicular columella composed of 15–20 slender, twisted elements.