Aplysina Nardo (Porifera, Verongida, Aplysinidae) from the Brazilian coast with description of eight new species
Author
Pinheiro, Ulisses Dos S.
Author
Hajdu, Eduardo
Author
Custódio, Márcio R.
text
Zootaxa
2007
1609
1
51
journal article
10.5281/zenodo.178878
91f273fc-e30b-4c2e-ae55-e7157868defa
1175-5326
178878
Aplysina alcicornis
sp.n.
(
Fig. 9
B, 11D, 14, Tab. VII)
Holotype
:
MNRJ
5473, Coral Head at Parque Nacional Marinho dos Abrolhos (BA),
12 m
depth, G. Muricy and E. Esteves
coll.
,
02/III/2002
.
Paratype
:
MNRJ
5472, 5474, southeast Patch Reef (Parque Nacional Marinho dos Abrolhos, BA),
12 m
depth, G. Muricy and E. Esteves
coll.
,
02/III/2002
.
Diagnosis
: Lamellar habit with flattened digitiform branches, conspicuous small apical digitiform projections and oscula with iris-type diaphragms situated in depressions on the surface of the sponge. Specimens turn to dark-brown in ethanol.
FIGURE 14:
A–D.
Aplysina alcicornis
sp.n.
Holotype (MNRJ 5473). A–B. habit after preservation. C. Skeletal architecture. D. Spongin fibres. Scale bars = A–B. 1 cm, C. 500 µm, D. 50 µm.
Description of the species:
The specimens are lamellar, with
11 cm
in width
10 cm
in height and
1 cm
in thickness. The general appearance somewhat resembles the fire coral
Millepora alcicornis
Linneus, 1758
, larger digitiform projections being observed at the base and the apex of the specimens. In the upper part of these larger projections, several much smaller apical digitiform projections up to
1 cm
long, can be observed (
Fig. 9
B). These fistules are frequently branching dichotomously or trichotomously, and remained on specimens after preservation (
Figs. 14A–B
). Oscula
0.3 cm
in diameter, bearing iris-type diaphragms are situated in depressions which occur close to the apical portion of the lamellas. Other oscula, with
0.1 cm
, open on the sides of the sponge. The surface is finely conulose. The colour is brown or yellow
in vivo
, turning to dark-brown after preservation in alcohol. Consistency is compressible.
Skeleton
: Choanosome with a delicate and irregular network of spongin fibers with amber coloured bark and thickness of 40–142 Μm (average 92 Μm) and a thick black or amber pith with thickness of 15–82 Μm (average 24 Μm;
Figs. 14C–D
; Table VII). In the small apical digitiform projections, the fibers present a dendritic arrangement. In these structures the fibers are composed mostly by the pith, with only a thin layer of bark.
TABLE VII:
Spongin fibres’ measurement data for
Aplysina alcicornis
sp.n.
(in micrometers; S.D. = Standard Deviation and N=30).
Specimens Locality* Fibers Piths
Distribution
: Provisionally known only from Parque Nacional Marinho dos Abrolhos, (Bahia State,
Brazil
;
Fig. 11
D).
Thinnest |
Mean |
Thickest |
S.D. |
Thinnest |
Mean |
Thickest |
S.D. |
Holotype Abrolhos, BA MNRJ 5473 |
50.0 |
96.1 |
142.5 |
20.1 |
15.0 |
32.1 |
82.5 |
14.1 |
Paratype Abrolhos, BA MNRJ 5472 Paratype Abrolhos, BA MNRJ 5474 |
57.5 40.0 |
97.3 82.6 |
140.0 107.5 |
19.5 17.2 |
15.0 15.0 |
25.5 25.8 |
67.5 35.0 |
12.5 5.3 |
*BA, Bahia State. |
Ecology
: All the specimens were collected at
12 m
depth, attached on the sides of coral heads.
Etymology
: The name of this species stresses its resemblance to the fire coral
Millepora alcicornis
.
Remarks
: The species which most closely resembles
A. alcicornis
sp.n.
is
A. cristagallus
sp.n.
which is described below.
Aplysina insularis
sensu Zea
(1987; Pl. 6, fig. 5) bear some resemblance to
A. alcicornis
sp.n.
(non
A. insularis
of authors). Nevertheless, Zea´s specimen is not considered conspecific on the basis of its markedly anastomosed cluster of otherwise cylindrical branches topped by oscula, which contrasts to the overall flattened habit of the new species.