Revision of the genus Latrunculia du Bocage, 1869 Porifera: Demospongiae: Latrunculiidae) with descriptions of new species from New Caledonia and the Northeastern Pacific (
Author
Samaai, Toufiek
Author
Gibbons, Mark J.
Author
Kelly, Michelle
text
Zootaxa
2006
2006-02-14
1127
1
1
71
https://biotaxa.org/Zootaxa/article/view/zootaxa.1127.1.1
journal article
10.11646/zootaxa.1127.1.1
11755334
5057828
E3B8BACE-1E5B-4E07-AB94-A4947F966483
Latrunculia
(
Biannulata
)
citharistae
Vacelet, 1969
(
Figs 1Q
,
5E
,
7
,
8A
;
Tables 2
&
3
)
Latrunculia citharistae
Vacelet, 1969: 195
Holotype
material.
Holotype
MNHNJV6814
Latrunculia citharistae
(
Vacelet, 1969: 195
)
.
Other material examined.
HBOM
10VI914007 (cross ref. TS 44), Canary Islands, Hierro; S.
Coast
, 3.75
NMI
120 DEG to Puerto Naos, depth
147 m
, collected by
HBOI
.
HBOM
13 VI914012 (TS 45), Canary Islands, Tenerife; W. coast, 2.03
NMI
120 Deg to
San Juan
, depth 477 fathoms, collected by
HBOI
.
HBOM
2VI914007 (Ts 42), Ilheus Selvagem, Selvagem Penuena; S. coast, 1.32
NMI
350 Deg to Pt
Sul
, de Ilheu, depth
232 m
, collected by Harbour Branch, 1996.
Description.
Massive, spherical, 5 x 4 x
3 cm
in diameter. Other specimens are small, semispherical, sponges up to
2 cm
high and
2 cm
wide (
Fig. 8A
). Surface smooth with numerous cylindricalshaped oscules; some at the apex larger than the rest,
2 mm
wide and
4 mm
high. The remainder is volcanoshaped mammiform processes, each with a distinct small opening at the top,
2 mm
high,
0.1 mm
wide. Ectosome thin and easily separable from underlying choanosome. Texture firm, resilient, soft but leathery. Colour in life is dark green; colour in preservative, choanosome dark brown and ectosome light brown (from
Vacelet, 1969
).
Vacelet (1969)
described the fresh
holotype
to have a dark brown colour and also possessing osculae and mammiform areolate porefields. Additionally,
Vacelet (1969)
noted that the
holotype
contained reddish embryos,
500 µm
diameter.
Skeleton.
The choanosomal skeleton consists of a loose, illdefined irregular polygonalmeshed reticulation formed by wispy tracts of styles, with no distinction between the primary and secondary tracts (
Fig. 5E
). The tracts range in width from
45–50 m
in thickness, and may form meshes that are
200 m
wide. Towards the surface the tracts become more vertically arranged. Interstitial spicules absent in choanosome. The surface of the ectosome is lined with an erect layer of noninterlocking anisodiscorhabds. Beneath the discorhabds in the ectosome is a thin tangentialparatangential layer of interlocking megascleres, approximately
75 m
wide.
Spicules.
Megascleres: styles are smooth, thin, centrally thickest, hastately pointed with a slight sinuous curve, 356 (345–382) x 5 (5) m, n=20;
Holotype
310–460 x
4–6 m
. Microscleres (
Fig. 1Q
): anisodiscorhabds, possessing identical median and subsidiary whorls symmetrically arranged around the shaft. The manubrium is a minute spinose base consisting of two or three whorls of spines, followed immediately by a smooth slender cylindrical shaft
12 m
long and
2.3 m
wide. The median and subsidiary whorls are circular, flat, slanted slightly in opposite directions and similar in diameter,
19 m
.
Each whorl is deeply notched and composed of eight spines, divided amongst three groups, which give three sets for each of them. The spines of the apical whorl are slanted slightly upwards, and divided, ending in a crownlike tuft of dichotomous spines. Acanthodiscorhabd length, 45 (41–48) x 5 (5) m, n=20.
Substratum, depth range and ecology.
Stalk of sea whip; dredge from slope/ rock rubble seems to very common; Specimen HBOM 2VI914007 was dredged from mud slopes and was associated with other sponges. Depth range:
147–232 m
Geographic distribution
(
Fig. 7
). Canary Islands, Mediterranean Sea.
FIGURE 8.
Gross morphology of
Latrunculia
spp
: A.
Latrunculia citharistae
Vacelet 1969
;
Latrunculia purpurea
Carter 1881
; C.
Latrunculia oparinae
Samaai and Krasokhin 2002
(REPRODUCED FROM SAMAAI AND KRASOKHIN 2002); D.
Latrunculia lunaviridis
Samaai and Kelly 2003
(REPRODUCED FROM SAMAAI AND KELLY 2003); E.
Latrunculia microacanthoxea
Samaai and Kelly 2003
(REPRODUCED FROM SAMAAI AND KELLY 2003); F.
Latrunculia duckworthi
Alvarez
et al
. 2002
(REPRODUCED FROM
ALVAREZ
et al
. 2002
); G.
Latrunculia kaakaariki
Alvarez
et al
. 2002
(REPRODUCED FROM
ALVAREZ
et al
. 2002
); H.
Latrunculia procumbens
Alvarez
et al
. 2002
(REPRODUCED FROM
ALVAREZ
et al
. 2002
); I.
Latrunculia wellingtonensis
Alvarez
et al
. 2002
(REPRODUCED FROM
ALVAREZ
et al
. 2002
)
Remarks.
Hinde and Holmes (1892)
(P. 219, FIG. 39) recorded a fossil anisodiscorhabd structure from the Oamaru Diatomite,
New Zealand
of a species that occurred during the late Eoceneearly Oligocene era. These authors also suggested that this form was a modification of a common plane, which ultimately gave rise to the phyllamentoustype discorhabd. The discorhabd structure of the extant
L.
(
B
.)
citharistae
conforms very closely in detail to the illustration and description of the fossil spicule given by
Hinde and Holmes (1892)
and could be considered as a recent flesh spicule of this
type
. The discorhabd structure of the extant
Latrunculia citharistae
differs however from the fossil spicule in that the spines of the apical whorl are slanted slightly upwards, as appose to forming a distinctive crownlike structure as in the fossil species (
Hinde and Holmes 1892
;
Latrunculia
sp.
, PL. XI, FIGS 39, 40). Apart from this
L. citharistae
the spicule also differ in length, being much smaller in size than what is recorded for the fossil species (
75 µm
). It is difficult to say whether the fossil acanthodiscorhabds are homologous to that found in the extant species, but it does suggest that several species of “latrunculids” with this form must have coexisted at the source of this assemblage (See also
Wiedenmayer 1994
).
The occurrence of this species in both the North Atlantic and the Mediterranean Sea, and its affinities with
New Zealand
(same flesh spicular structure) probably suggest a Tethyan origin of this species complex. At present
L. citharistae
is here restricted to the deepwater North Atlantic and Mediterranean regions and has not been recorded in the southern hemisphere (
Table 2
).
Structurally the anisodiscorhabd differs from the variety of forms presently found within the genus, in that it posses a slender cylindrical shaft with the two lobate whorls in the middle portion of the shaft. Its relationship to the other species with flesh spicules is one of assumption and could only be resolved with additional data.