Deltocyathus corrugatus Cairns 1999

New Caledonia waters from 18°59.93’S, 163°13.55’E to 23°02.53’S, 166°58.18’E (Kitahara & Cairns, 2009), including Loyalty Islands (Cairns 1995), 250-600 m. Previous records: from southern Great Barrier Reef, Australia (Wells 1984) to Norfolk Ridge, New Zealand (Cairns 1995), 73-390 m.

Corallum circular. Calice lancetted, lancets correspond to each C3 fl anked by C4. Corallum usually white but sometimes slightly reddish-brown pigmented. Base fl at to slightly convex, having a small scar of previous attachment (during early stages) in centre. All costae well developed. C1-2 more prominent near calicular edge, becoming a row of granules near centre of base. C3 thickest and tallest costae, extending up to 2 mm and normally upturned slightly beyond calicular edge as granulated costal spines. C4 and C3 form a broad three-step ridge. All costae granulated specially near calicular edge, and a small low granule ridge is present beside each C1-2. Septa hexamerally arranged in 4 complete cycles (S1≥S2>S4>S3). S1 independent, extending half distance to columella and bearing a wide lamellar palus, which is often fused to columella. S2 equal to or slightly less wide than S1, also bearing a pali of same size of P1, forming a crown more recessed from columella than the crown formed by P1. S3 smallest septa, bearing the tallest pali which fuse to inner edge of near P2 by a porous lamella. S4 slightly wider than S3, and have a spinose margin. Each S4 fuses the adjacent P3 through a long porous lamella. All pali equal sized (P1 sometimes dimorphic) and septa and palar faces bear pointed granules. Fossa shallow with an elliptical papillose columella.

azooxanthellate

280-390 m