Bulletin 20 - Peabody Museum of Natural History - Yale University

30 A SYSTEMATIC STUDY OF THE DEMOSPONGIAE OF JAMAICA
Indies. P. carbonaria (Lamarck) as described by de Laubenfels from Dry Tortugas is a
black sponge with larger oxeas and a network of subdermal canals. The white P. coela
de Laubenfels (1950a) of Bermuda differs from the Jamaican sponges by its smaller
spicules and less robust spicule tracts. The type species of Pellina, P. semitubulosa, described
from the Mediterranean, is also white in color. The Adriatic specimens studied
by Babic (1922) and Keller (1878) do have spicules similar in size to those of my specimens.
Topsent's Mediterranean specimen, however, has more robust oxeas and a second
category of small ectosomal microxeas. He reported an extensive network of subdermal
canals in the basal regions of his material. Schmidt (1862, 1870) and Topsent both
emphasized the presence of a well-developed, easily detachable skin in their specimens.
The Jamaican sponge, by contrast, has a closely adherent dermal skeleton.
A
GENUS SIGMADOCIA de Laubenfels
Sigmadocia caerulea n. sp.
(Text-fig. 5; plate III, fig. 4)
50//
Fig. 5. —Spicules of Sigmadocia caerulea. A. Oxea. B. Sigmas. YPM 5037. Holotype.
HOLOTYPE. YPM 5037. Rasta's wreck. July 19, 1959.
HABITAT. Common on pilings and mangrove roots on the outside of the Port Royal
mangrove thicket. Sponges of similar appearance were collected at Drunkenman's Cay in
a sandy turtle grass bed.
SHAPE. The base is thickly incrusting to massive. Many of the oscules, particularly in
the Port Royal specimens, are at the apex of cylindrical to volcano-shaped projections
ivhich may be several centimeters in height. The projections have axial cloacae and thick
-walls.
COLOR. Both the surface and the interior are light blue in the living sponge. The
specimens become beige to drab in alcohol.
CONSISTENCY. The Port Royal specimens are soft but very easily broken. The specimens
from Drunkenman's Cay are heavily penetrated by coarse algal strands. They are
stiff to somewhat compressible.
SURFACE. The oscules may be as much as 5 mm in diameter. The surface, while even,
varies from smooth to rough. Some areas of the sponge, particularly on the base, have
a detachable dermal layer.
ECTOSOME. Parts of the sponge are covered by a tangential, largely unispicular network.
The three- or four-sided network is bound by small amounts of spongin at the
nodes. Several dermal pores may be inclosed within a mesh. Typical pore sizes are
20 X 17, 12 X 20, and 27 X 24 ^. Small subdermal spaces may be present. In other
regions, the architecture is of the haliclonid type, with spicules projecting beyond the
surface.
ENDOSOME. A rather confused pattern of vague tracts, scattered spicules and a largely
unispicular spongin-bound network. In the Port Royal specimens, sigmas are abundant
throughout the sponge. Much of the interior of the cay sponges is occupied by algae.
Sigmas are exceedingly rare, even in algae-free portions.
SPICULES, (a) Oxeas, slightly curved, fusiform to wedge-shaped, 117-200 X 5-9 p. Port
Royal specimens, 128-200 x 5-9 /A- Cay specimens, 117-177 x 3-5 /*,. Thinner develop-