Deep-water sponges (Porifera) from Bonaire and Klein Curaçao, Southern Caribbean
Author
Van Soest, Rob W. M.
Naturalis Biodiversity Center, Department of Marine Zoology, P. O. Box 9517, 2300 RA Leiden, The Netherlands.
Author
Meesters, Erik H. W. G.
Institute for Marine Resources and Ecosystem Studies (IMARES), Wageningen UR, P. O. Box 57, 1780 AB Den Helder, The Netherlands. E-mail: erik. meesters @ wur. nl
Author
Becking, Leontine E.
Naturalis Biodiversity Center, Department of Marine Zoology, P. O. Box 9517, 2300 RA Leiden, The Netherlands. & Institute for Marine Resources and Ecosystem Studies (IMARES), Wageningen UR, P. O. Box 57, 1780 AB Den Helder, The Netherlands. E-mail: erik. meesters @ wur. nl & University of California Berkeley, Department of Environmental Science, Policy and Management (ESPM), 130 Mulford Hall, Berkeley, CA 94720 - 3114, USA. E-mail: lebecking @ gmail. com
text
Zootaxa
2014
2014-10-29
3878
5
401
443
journal article
5247
10.11646/zootaxa.3878.5.1
5247e933-3152-40d5-ae19-cce84a3dad7f
1175-5326
4948908
11145FA0-2CB5-460A-B7A6-9A634C778982
Parahigginsia strongylifera
new species
Figures 14a–d
,
15a–f
Material examined
.
Holotype
:
RMNH
Por.
9251,
Caribbean Netherlands, Bonaire
(Dive 4),
112.08°N
68.2938°W
, depth
238 m
, on a limestone rockwall, coll.
L.E. Becking
&
E. Meesters
, field nr. BON4/
BDR048
,
1 June 2013
.
FIGURE 14
.
Parahigginsia strongylifera
n. sp.
, habit in situ, b. detail of habit in situ, c. preserved holotype RMNH Por. 9251, d. spicules of holotype.
FIGURE 15
.
Parahigginsia strongylifera
n. sp.
, holotype RMNH Por. 9251, a–c. SEM images of the spicules, a. strongyle, b. acanthomicroxea, c. details of apex and middle part of acanthomicroxea, d–e. light microscopy images of skeleton, d. cross section of skeleton, e. detailed view of peripheral skeleton showing ectosomal cover of acanthomicroxeas.
Description
.
Pale blue, encrusting sponges (
Fig. 14a
) forming small lobes with raised oscules (
Fig. 14b
), individual lobes approximately 2 x 1 x
1 cm
in size. The preserved
holotype
material consists of fragments of approximately
1–2 cm
in size (
Fig. 14c
). Individual lobes may coalesce with nearby lobes, and may be connected by thin tissue strands on the substratum. Consistency soft, easily damaged.
Skeleton
.
The ectosomal skeleton consists of a thin layer of spined microxeas (
Fig. 15e
) covering a confused choanosomal reticulation (
Fig. 15d
), constructed from individual strongyles or vaguely aligned bundles of two or three. No clearly developed meshes or tracts. Microxeas are also profusely present in the choanosome.
Spicules
(
Figs. 14d
).
Strongyles, acanthomicroxeas.
Strongyles (
Fig. 15a
), curved, often with slightly asymmetrical ends, 290–
341
–370 x 10–
15
–
18 µm
Acanthomicroxeas (
Figs. 15b–c
1
), curved gently, not abruptly, with thin somewhat irregularly distributed spines (denser at the apices and in the center), 75–
93
–120 x 1–
1.8
–
2.5 µm
.
Ecology and distribution
.
Deep water (
238 m
) off the coast of SW
Bonaire
, on volcanic outcrops.
Etymology
.
The name refers to the strongyle megascleres.
Remarks.
The genus
Parahigginsia
is so far monotypical, erected for the
New Zealand
deep water species
P. phakelloides
Dendy, 1924
, subsequently reported also from
New Caledonia
by
Lévi & Lévi (1983)
. The assignment of our specimen to this genus is based on the combination of a dense isotropic skeleton of smooth diactines arranged in vague bundles and an ectosomal cover of thin curved acanthoxeas.
P. phakelloides
has a similar skeleton, but the megascleres are more definitely curved oxeas, whereas
P. strongylifera
n. sp.
predominantly has (aniso-)strongyles. The megascleres and microscleres of both species are in the same size range.
P. phakelloides
has a lamellate growth form, up to
14 cm
high,
8 cm
wide and
2.5 mm
thick, quite different from the encrusting-lobate
P. strongylifera
n. sp.
Both species occur at comparable depths (
P. phakelloides
was collected from
126 m
).
Hooper (2002)
assigned the genus
Parahigginsia
to the family
Desmoxyidae
, for priority reasons renamed as
Heteroxyidae
in
Van Soest & Hooper (2005)
. This family is likely polyphyletic (
Morrow
et al.
2012
).
Parahigginsia
was reassigned to a family
Stelligeridae
, along with several other heteroxyid genera. Since only limited evidence of mostly molecular nature was presented to justify the proposed reassignment, we prefer to retain
Parahigginsia
in the family
Heteroxyidae
until a comprehensive integrative classification of these genera and families has been published.