The genus Litophyton Forskål, 1775 (Octocorallia: Alcyonacea: Nephtheidae) from Australia
Author
Van Ofwegen, Leen P.
text
Zootaxa
2020
2020-04-16
4764
1
1
131
journal article
22824
10.11646/zootaxa.4764.1.1
55f6b110-0a37-45fe-be1c-34e9a035fe0e
1175-5334
3764923
urn:lsid:zoobank.org:pub:53C5289A-156C-4AF1-B84A-73099A332C05
Litophyton rowleyensis
sp. nov.
(
Figs. 21
a-e, 13b, g, 22-25)
Material examined.
Holotype
NTM C10780
,
Western Australia
,
Rowley Shoals
,
Clerke
reef, depth
5-10 m
,
18 July 1987
, coll.
J. Hooper
;
paratypes
: NTM C5804, two specimens, same data as
holotype
; NTM C5807, two specimens,
Western Australia
, Rowley Shoals, Clerke reef, collected in a lagoon, depth
10 m
,
18 July 1987
, coll. J. Hooper; NTM C10722, North-Western
Australia
,
July 1987
, coll. P. Alderslade; NTM C10737; same data as
holotype
; NTM C10769,
Western Australia
, Rowley Shoals.
Description.
The
holotype
NTM C10780 is
4.5 cm
high and
8 cm
wide, the stalk is
2 cm
high (
Fig. 21a
). The polyps are up to
0.6 mm
wide and
0.75 mm
high, and are grouped in long catkins.
Polyps
. With irregular arrangement of sclerites in eight points (
Fig.
13g
). Abaxial and lateral point sclerites are spindles with simple tubercles and spiny distal part, largest present abaxially, up to
0.45 mm
long (
Fig. 22a
), towards the adaxial points they become smaller (
Fig. 22b
). Tentacles with curved scales up to
0.10 mm
long (
Fig. 22c
). Adaxial side of the polyp stalk with straight rods up to
0.15 mm
long (
Fig. 22e
), and platelets up to
0.05 mm
long (
Fig. 22d
). Supporting bundle composed of one or two spindles up to
2.50 mm
long, with simple tubercles and a spiny or sometimes smooth tip projecting for a maximum distance of
0.80 mm
(
Fig. 22f
). Many polyp sclerites have an optically black inner core.
Surface layer top stalk
. Spindles and unilaterally spinose spindles, up to
1.50 mm
long, with simple tubercles (
Fig. 22
g-h).
Surface layer base stalk
. Capstans, derivatives of capstans, spindles, and unilaterally spinose spindles, with simple tubercles (
Fig. 22
i-j). The spindles are up to
1.50 mm
long.
Interior stalk
. Spindles with pointed ends (
Fig. 22
k-l), up to
1.50 mm
long, with simple tubercles (
Fig.
22m
).
Etymology.
Named after the
type
locality.
Distribution
.
Western Australia
: Rowley Shoals.
Remarks
. The specimens of
Litophyton rowleyensis
show a considerable variation concerning colony shape (
Fig. 21
a-e) and sclerites (
Figs. 22-25
). One of the
paratypes
of NTM C5807 (
Fig. 21d
) and NTM C10722 (
Fig. 21c
) lack the basal part of the stalk and show shorter internal spindles, only up to 1.00 mm long (
Fig. 24e
), with complex tubercles, and less spiny surface stalk sclerites (
Fig. 23
j-k). The other
paratype
of NTM C5807 (
Fig. 21e
) shows the longest internal stalk spindles, up to 2.00 mm long (
Fig. 25j
). One of the
paratypes
of NTM C5804 (
Fig. 21b
) has many rather smooth internal stalk sclerites (
Fig. 24
a-c).
The
paratype
of NTM C5807 having the largest internal stalk sclerites (
Fig. 25j
) suggests this is the specimen with most of the stalk intact as in general the internal stalk sclerites become larger towards the base of the stalk (see material and methods). Apparently also the
holotype
lacks a bit of the base which is sometimes difficult to observe as with collecting a broken stalk tends to close fast (my field observations while collecting nephtheids).
The other
Litophyton
species with projecting supporting bundle spindles with a smooth tip,
L. pseudorowleyensis
sp. nov.
, has the supporting bundle projecting for a maximum distance of only
0.30 mm
. Furthermore, it has far less sclerites in the polyp stalk.