Protosuberites sisyrnus (de Laubenfels 1930)

Figure 10

Material examined. Fragment of holotype, found in the Natural History Museum Los Angeles collection, labeled as “21413 (Part of type)”, with collection information that fits holotype. The holotype is also stored in the Smithsonian as USNM21413. Collected South of the breakwater, San Pedro, California, 45 m, 4/5/1924.

Morphology. Sponge is encrusting on a tangled mass of polychaete tubes and other debris. Visibly hispid. Difficult to further characterize due to the age and complexity of the sample. Light brown post-preservation.

Skeleton. Not investigated; previously described as erect tylostyles in the ectosome and few spicules, in confusion, in the choanosome.

Spicules. Tylostyles; both straight and slightly curved spicules are common, most with round terminal heads, but occasionally subterminal. Consistent thickness through shaft until reaching a sharply tapering point. Considerable variation in length and width but distribution unimodal. 246–386–574 x 7–12–19 μm (n=50)

Distribution and habitat. Described from two samples dredged from 45–54 m near Los Angeles and Catalina Island in Southern California. Museum records indicate occurrences in British Columbia, but this remains to be confirmed, as samples we examined were misidentified (see remarks).

Remarks. We were unable to locate any samples of this species in the field (previously collected samples were from a depth range we were not able to investigate). Vouchers previously identified as Protosuberites were loaned to us from British Columbia, but these proved to be misidentified (they are likely in the Microcionidae, as spicules consist of palmate chelae, toxas, and two sizes of acanthostyles). We attempted to sequence DNA from several loci from the holotype fragment in the Natural History Museum of Los Angeles but were unsuccessful. The quantitative spicule data presented here should aid in future attempts to locate and characterize this species.