Timea diplasterina, Rützler, Klaus, Piantoni, Carla, Van, Rob W. M. & Díaz, Cristina, 2014

Rützler, Klaus, Piantoni, Carla, Van, Rob W. M. & Díaz, Cristina, 2014, Diversity of sponges (Porifera) from cryptic habitats on the Belize barrier reef near Carrie Bow Cay, Zootaxa 3805 (1), pp. 1-129 : 45-48

Timea diplasterina new species

( Figures 3 e, 25)

Material. Holotype: USNM 1228986, Carrie Bow Cay back reef, near crest, underside of Acropora palmata coral rubble, 0.3 m; K. Ruetzler coll. 23 Apr 1974.

Diagnosis. Timea with two size classes each of tylostyles and spheroxyasters, with diplasters of one size class added to the microsclere complement.

External morphology. The holotype was originally a thin (0.2–3 mm), lumpy crust covering about 30 cm 2 of the rock surface. There were a few small (> 1 mm), irregularly dispersed openings (oscula). Surface rough to the touch (from protruding spicule brushes), consistency firm, live color ranging from drab to dull orange brown.

Skeleton structure. Spicule bundles (bouquets) rising from the base to and beyond the surface, points directed outward. Microscleres, all types mixed, occur throughout the tissue but are densest near the base and in the ectosome.

Spicules. Tylostyles straight or slightly bent, with spherical head that may be subterminal, slightly bent sideways, or show an extra swelling at the base, with pointed ends often dull or rounded; two size categories, I: 325–700 x 14–23 (555 x 17) Μm; II: 129–350 x 5–13 (272 x 10) µm. Spheroxyasters (center diameters: 37–42 % of total diameters), also in two size classes, the larger one (I) has smooth rays which, however, may be branched near the points: 38–59 (48) µm; spheroxyasters II have microspined rays: 8–30 (17) µm; diplasters, with smooth rays, some appearing like transition stages to spirasters:13–27 (20) µm.

Ecology. Found only once, cryptic under coral rock, 0.3 m.

Distribution. Belize.

Etymology. Named for the addition of diplasters to the euasters typical of the genus.

Comments. This species is quite similar in microsclere composition to Timea bioxyasterina Mothes, Santos and Campos (Mothes et al., 2004 : 3, fig. 3; larger oxyasters with smooth rays, smaller ones with microspined rays) except that euasters are spheroxyasters (with centers>1/3 of total diameter) instead of oxyasters (center <1/3 diameter) and that there is the addition of diplasters. Discovery of a species of Timea with diplasters and transitional spirasters among its microscleres demonstrates the closeness of the family Timeidae to Spirastrellidae (see discussions in Rützler (2002)).

Figures

FIGURE 3. In-situ photographs of new sponge species reported in this contribution (measurements in parentheses are picture widths): a, Tetralophophora mesoamericana (3 cm); b, Geodia cribrata (12 cm); c, Placospongia caribica on “ pseudostalactite ” made up by calcareous serpulid tubes (5 cm); d, Prosuberites carriebowensis (adjacent to Monanchora arbuscula to the lower right) (4 cm); e, Timea diplasterina (8 cm); f, Timea oxyasterina (4 cm); g, Rhaphidhistia belizensis (14 cm).