New taxa and arrangements within the family Latrunculiidae (Demospongiae, Poecilosclerida)
Author
Kelly, Michelle
Author
Sim-Smith, Carina
Author
Stone, Robert
Author
Reiswig, Toufiek Samaai Henry
Author
Austin, William
text
Zootaxa
2016
4121
1
1
48
journal article
38929
10.11646/zootaxa.4121.1.1
214dc5a7-b23a-4140-b251-3a564b18bb9e
1175-5326
265513
2C978846-61DD-48BD-87BE-0BC22D0CABF2
Latrunculia
(
Uniannulata
)
velera
Lehnert, Stone & Heimler, 2006
subgen. nov.
, comb. nov.
(
Fig. 2
B, 9, 16AH;
Tables 8
,
9
)
Latrunculia velera
Lehnert, Stone & Heimler, 2006
: 27
–30;
Fig. 15
A–F, 16A–D.
Latrunculia velera
,
Abbas
et al.
2011
: 2429
‒2430;
Fig. 8
D;
Stone
et al
. 2011
: 114
,
Fig. 1–3
; 141; 145; 185, Fig. A, B; 186, Fig. C–F; 187, Fig. G–J.
Material Examined.
None.
Distribution.
Central Aleutian Islands.
Description.
Club-shaped to sub-globose sponge with a flattened, circular to kidney-shaped apex (
Fig. 9
A, C), about
12 cm
diameter, restricted base about
1–2 cm
diameter. Slightly elevated cylindrical oscules regularly dispersed across a flat apex, areolate pore fields not visible, possibly positioned laterally. Surface smooth between the oscules, interior cavernous, markedly fibrous, wrinkled in the preserved condition (Fig. B), Overall texture leathery, slightly elastic, and easily torn. Colour in life dull brown, choanosome slightly darker.
Skeleton.
Ectosomal skeleton, a detachable, paratangential layer of megascleres upon which sits a singlelayered palisade of anisodiscorhabds. Choanosomal skeleton, a wispy reticulation of megascleres in tracts (modified from
Lehnert
et al.
2006
and
Stone
et al.
2011
).
Spicules.
Megascleres (
Fig. 9
D), styles with lightly spined heads very lightly and irregularly spined distal ends (
Fig. 9
E), 500–540 × 9–11 µm.
Microscleres (
Fig. 9
F), anisodiscorhabds, manubrium, a single stump with denticulate margins, in the same line as the shaft. Basal whorl a ring of thick sculpted spines with rows of tiny teeth that curve along the edges of the sculpted sections, spines orientated obliquely towards manubrium. Median whorl a regular, thick ‘saucer’ with incised, sharply denticulate margins, located approximately centrally along the axis. Undifferentiated subsidiary/ apical whorl arises obliquely from the shaft, from just above the median whorl, forming a thick-walled, concave chalice with finely notched, beaded, denticulate margins. The apex sits atop the slightly concave subsidiary/apical cup and ranges in shape from a lemon-squeezer with five prominent beaded, denticulate ridges extending from the tip to the base, to an opening flower bud, with the tips of the five enfolded spines expanded out (
Fig. 9
F, I), 37–43 µm long.
Substrate, depth range and ecology.
Locally common in the central Aleutians region where it is found attached to bedrock, boulders and cobbles between 412 and
1009 m
, but relatively rare at depths shallower than
600 m
.
FIGURE 9.
Morphology, megascleres and microscleres of
Latrunculia
(
Uniannulata
)
velera
Lehnert, Stone & Heimler, 2006
subgen. nov.
comb. nov.
:
A.
Holotype USNM 1084238,
in situ
;
B.
Preserved holotype, scale = 1 cm;
C.
Uncollected specimen, west Amchitka Pass, central Aleutian Islands, 929 m, distance between red laser dots is 10 cm;
D.
Head of megasclere showing heavy conical spines, scale = 20 µm;
E.
Distal end of megasclere showing retrovert spines, scale = 20 µm;
F.
Range of mature anisodiscorhabds, scale = 20 µm;
G.
Protorhabds, scale = 20 µm;
H.
Protorhabd showing undifferentiated subsidiary and apical whorls, and differentiated manubrium and basal whorl, scale = 20 µm;
I.
Apex of microsclere showing apical region with ‘lemon-squeezer’ apex, saucer-like undifferentiated apical and subsidiary whorl, and incised, denticulate petals or paddles of the median whorl, scale = 20 µm. Fig. 9D–I taken from holotype USNM 1084238, Fig. 9A, B reproduced from Stone
et al
. (2011), and Fig. 9C–F, I were modified from Fig. 15A, C, E, F, and Fig. 16B, C and D of Lehnert
et al
. (2005), with permission from
Zootaxa
(Magnolia Press).
Remarks.
The anisodiscorhabds of
L
. (
U
.)
velera
are similar in general form to those of
L
. (
U
.)
oparinae
, with the undifferentiated subsidiary and apical whorls, and the clearly differentiated manubrium and basal whorl. However, the anisodiscorhabds in each species differ markedly in the degree of micro-ornamentation; in
L
. (
U
.)
velera
the anisodiscorhabds are very smooth with beaded denticulate margins in the apical region, while in
L
. (
U
.)
oparinae
all features are microspined. The megascleres of
L
. (
U
.)
velera
(500–540 µm) are also considerably larger than those of
L
. (
L
.)
hamanni
sp. nov.
(433–508 µm) and
L
. (
U
.)
oparinae
(400–464 µm), but similar in length to those of
L
. (
B
.)
lincfreesei
sp. nov.
(480–590 µm). The latter species, however, has been recorded much further east, in the Gulf of Alaska. While
L
. (
U
.)
velera
occurs in the same general area as
L
. (
L
.)
hamanni
sp. nov.
and
L
. (
U
.)
oparinae
, it occurs at depths well beyond these two species, from about
400–1000 m
.