Sponges associated with octocorals in the Indo-Pacific, with the description of four new species
Author
Calcinai, Barbara
Author
Bavestrello, Giorgio
Author
Bertolino, Marco
Author
Pica, Daniela
Author
Wagner, Daniel
Author
Cerrano, Carlo
text
Zootaxa
2013
3617
1
1
61
journal article
39041
10.11646/zootaxa.3617.1.1
6174b35e-3228-4d50-a6ed-844e244f8b64
1175-5326
248150
4DCCD152-65DA-44A3-AB19-59811384E1E7
Spirastrella
cf.
cunctatrix
Schmidt, 1868
(
Fig. 4
A–G)
Examined material. Sample HL 162:
Vietnam
, Hang Trai
Island
, Hang Du II Lake,
5 m
,
26 April 2004
.
Description. The sponge, about
1 mm
thick, covers the basal stolons and the proximal portion of a colony of
Carijoa riisei
, as well as a bivalve shell (
24 cm
2) where the octocoral colony is settled (
Fig. 4
A). The surface is smooth, slightly pink in ethanol, with evident subectosomal canals.
Skeleton. Spirasters II are concentrated in the ectosome forming a thick superficial crust (
Fig. 4
B). Choanosome with scattered spirasters I and II; tylostyles are grouped in multispicular tracts with tyles towards the substrate (
Fig. 4
C) and tips protruding beyond the surface.
Spicules. Straight tylostyles with hastate tips and generally rounded heads (
Fig. 4
D, G), 225 – (341.5 ± 66.9) – 450
x 5
– (8.5 ± 2.3) – 10 μm, with evident axial canal starting from the head. Spirasters in two categories: spirasters I large, with thick, slightly bent axis and conical large spines (
Fig. 4
E, G), 30.5 – (46.3 ± 6.9) – 60.5
x 5
– (7.5 ± 1.3) – 10 μm, numerous spicules have a straight and thin axis; spirasters II small, with spiralled axis or rabd-like with straight axis; numerous intermediate forms (
Fig. 4
F, G), 5 – (8.7 ± 1.4) – 12.5 μm.
Distribution and remarks. The spicule shape of the Vietnamese sample and the skeletal organisation are very similar to
S. cunctatrix
Schmidt, 1868
as described and illustrated by
Rützler (2002)
(see
Fig. 5
: 223). The
holotype
has tylostyles with oval or rounded heads, 480
x 8
μm in length on average; small spirasters of
10 – 25 x
5 – 23 μm and large spirasters of 28 – 50
x 23 – 35
μm (
Rützler, 2002
) slightly larger than those of the Vietnamese specimen.
Spirastrella cunctatrix
was originally described from the Mediterranean Sea, and later recorded also in the Indo- Pacific area (Mergui-Burma Archipelagos (
Carter 1887
),
Hong Kong
(van
Soest 1982
),
Madagascar
(
Vacelet & Vasseur 1971
), the Red Sea (
Lévi 1965
), and
Vietnam
(
Azzini et al. 2007
)) but its distribution has to be considered restricted to the Atlanto-Mediterranean area (van
Soest et al. 2011
). Further molecular studies could clarify its cryptogenic nature. The species was always described as a thin encrusting sponge, with the exception of the massive sponge record from the Red Sea (
Lévi 1965
).