Protosuberites Swartshewsky, 1905

Calcinai, Barbara, Bavestrello, Giorgio, Bertolino, Marco, Pica, Daniela, Wagner, Daniel & Cerrano, Carlo, 2013, Sponges associated with octocorals in the Indo-Pacific, with the description of four new species, Zootaxa 3617 (1), pp. 1-61 : 6-7

Genus Protosuberites Swartshewsky, 1905

Protosuberites epiphytum ( Lamarck, 1815) ( Fig. 2 A–D) ( Tab. 1 )

Examined material. Sample HK 4 and sample HK O’ahu: Hawai’i, O’ahu Island, about 1 m, August 2003; sample HK O’ahu 2006: Hawai’i, O’ahu Island; sample HK 7: Hawai’i, O’ahu Island, Hawai’i Kay, depth between 0.5 – 2 m, 31 May 2007.

Description. Encrusting sponge, about 0.5 mm thick covering the branches and the body walls of the polyps of Carijoa riisei ( Fig. 2 A). Several branches of the coral, up to 10 cm long, were examined. In situ sponges are yellow ( Fig. 2 A), pale yellow in ethanol.

Skeleton. A layer of echinating tylostyles with the head in contact with the octocoral surface; above this a second layer of tylostyles producing a hispid surface ( Fig. 2 B, C).

Spicules. Tylostyles, numerous with a characteristic flattened and lobed head (up to 4 projections per tyle) ( Fig. 2 D), in a large size range 22.5 – 350 x 2 – 7.5 µm. Refer to Tab. 1 for complete measurements.

Distribution and remarks. Australia (see van Soest et al. 2011). This is a new record for Hawai’i. The Hawaiian specimens fit well with P. epiphytum described by Lamarck (1815), in terms of general morphology as well as spicule and skeleton features. This species was considered cosmopolitan but van Soest & de Kluijver (2003) pointed out that the records from the Atlantic-Mediterranean area have to be considered as a distinct species ( P. denhartogi van Soest & de Kluijver, 2003 ), thus suggesting that P. e p i p h y t u m is restricted to the Pacific Ocean.

Inside the family Suberitidae the presence of tylostyles with flattened lobate tyles is considered a diagnostic element of the genus Terpios (van Soest 2002a) ; the species of this genus are characterised by the lack of a special ectosomal skeleton and by choanosomal tylostyles strands.

On the contrary the genus Protosuberites has a choanosomal skeleton of tylostyles erect on the substrate and ectosomal tylostyles in brushes. Tylostyles are often in a large size range, but have no characteristic flattened or wrinkled tyles.

We prefer to attribute this species to the genus Protosuberites mainly on the base of the skeletal organisation, considering the choanosomal architecture characters as the trustworthiest in systematic studies (Hajdu & van Soest, 1996).

Figures

FIGURE 2. Protosuberites epiphytum (Lamarck, 1815). A, Sponge on Carijoa riisei in situ; B – C, Skeletal organisation; D, Characteristic flattened, lobed heads of tylostyles.

Tables

TABLE 1. Spicule dimensions in µm of Protosuberites epiphytum (Lamarck, 1815).

HK 4	22.5 – (154.5 ± 86.1) – 310 x 2 – (4.4 ± 1.7) – 7.5
HK Oahu	40 – (192.5 ± 97.3) – 350 x 2 – (4.4 ± 1.8) – 7.5
HK Oahu 2006	100 – (211 ± 81.2) – 345 x 2.5 – (5.2 ± 1.1) – 7.5
HK 7	102.5 – (167.1 ± 55.4) – 275 x 2.5 – (3.7 ± 0.9) – 5

Tylostyles