Trikentrion catalina (Sim & Bakus, 1986)

Soest, Rob van, Carballo, Jose Luis & Hooper, John, 2012, Polyaxone monaxonids: revision of raspailiid sponges with polyactine megascleres (Cyamon and Trikentrion), ZooKeys 239, pp. 1-70 : 44-46

Trikentrion catalina (Sim & Bakus, 1986) Figs 25 A–F

Cyamon catalina Sim and Bakus 1986: 18, fig. 4; Lee et al. 2007: 211 (California).

Not: Trikentrion catalina ; Gómez et al. 2002 = Trikentrion helium .

Material examined.

Holotype USNM 33631, preserved in alcohol, California, Santa Catalina Island, Bird Rock, 33.45°N, 118.4833°W, on rocky cliff at 50 m depth, coll. K. McCleneghan.

Not examined: paratype BMNH 1985 (reg. nr. unknown), Santa Catalina Island, Ship Rock, on rock at 46 m depth, coll. R. Given.

Description.

Flabelliform sponge (Fig. 25A), measuring 15 × 8 by 0.4 cm, attached to rocks by a 3 × 0.6 cm stalk. Surface hispid. No oscules apparent. Consistency firm and leathery. Color reddish orange (alive), pale beige (alcohol).

Skeleton (Fig. 25B): choanosome densely packed with three-claded polyactines; ectosome with long, relatively thick styles surrounded by dense bouquets of short thin styles; trichodragmata commonly observed especially in the peripheral parts.

Spicules: long (thin) styles, short thin styles, polyactines, trichodragmas.

Long (thin) styles (Fig. 25C), usually broken and only a few could be measured: 1400-5400 × 8-40 µm, so not really thin.

Short thin styles (Fig. 25D), 130 –611.3– 730 × 3 –5.6– 8 µm,

Polyactines (Figs 25E, E1), predominantly three-claded, with spined shorter basal cladi (Fig. 25E1), occasionally with few or no spines on the basal cladi, and smooth, longer, relatively pointed lateral cladi; occasionally four-claded; size basal cladi 78 –98.7– 126 × 16 –25.3– 31 µm, lateral cladi 156 –197.7– 236 × 18 –24.4– 29 µm.

Trichodragmas: straight, with lightly spined raphides (Figs 25F, F1), 63 –79.3– 88 × 7 –10.2– 13 µm.

Distribution.

Santa Catalina Island, Southern California.

Ecology.

On rocks, from 46-50 m depth.

Discussion.

This species is assigned to Trikentrion , because of the flabellate shape resembling Trikentrion flabelliforme Hentschel (1912), the sagittal polyactines, three-claded with spines only on the basal cladus, and the possession of trichodragmas. It is similar to Trikentrion helium in the lack of genuine choanosomal oxeas, and the short basal cladi of the polyactines. Remarkably, when describing Trikentrion catalina , Sim & Bakus (1986) did not notice - they did not discuss Trikentrion helium - the similarities with their species. Specimens assigned to Trikentrion catalina by Gómez et al. (2002) are considered to be long to Trikentrion helium (see above).