A new asterinid genus from the Indo-West Pacific region, including five new species (Echinodermata: Asteroidea: Asterinidae)
Author
O'Loughlin, P. Mark
Author
Rowe, Francis W. E.
text
Memoirs of Museum Victoria
2005
2005-12-31
62
2
181
189
https://museumsvictoria.com.au/collections-research/journals/memoirs-of-museum-victoria/volume-62-issue-2-2005/pages-181-189/
journal article
10.24199/j.mmv.2005.62.6
1447-2554
12208000
Ailsastra amezianeae
sp. nov.
Figures 1
,
2b
,
3b
,
4d–f
Material examined
.
Holotype
(dry). NW
Madagascar
,
Nossi Be, G
. Cherbonnier,
6 Oct 1959
,
MNHN
EcAs 11845.
Paratype
(dry, part dissected). Type locality,
G. Cherbonnier
,
2 Dec 1959
,
MNHN
EcAs 11846
.
Diagnosis
.
Ailsastra
with, at R =
10 mm
, discrete, short, broad rays, R/r about 1.5; 8 longitudinal series of papulae across mid-ray; abactinal spinelets stout, short, up to about
0.10 mm
long; inferomarginal spinelets twice as long as superomarginal spinelets; up to 4 actinal interradial spines per plate.
Description
. Integument evident; 5 rays, R up to
10 mm
; rays discrete, short, wide at base, broad, tapered to narrow rounded end, R/r about 1.5; single madreporite, not fissiparous; abactinal gonopores. Carinal series of plates broadly visible, not below adcarinal plates, doubly papulate, other abactinal ray plates sometimes slightly incurved proximally for single papula, 3 longitudinal series of papulae on each upper side of rays, 8 longitudinal series of papulae at mid-ray; disc close to regularly defined by 5 radial, 5 interradial plates; spinelets glassy, stout, splay-pointed subsacciform, up to about 16 spinelets in double or single series across proximal edge of plates, up to about
0.10 mm
long, up to
6 in
subpaxilliform tuft on distal interradial plates, proximal and distal spinelets subequal; up to about 6 short stout sacciform superomarginal spinelets per plate, up to about 16 longer sacciform inferomarginal spinelets per plate, up to twice as long as superomarginal spinelets. Actinal spines per plate: oral 2–5; suboral 0; furrow (proximal) 3; subambulacral 2–3; adradial actinal 2–4; interradial 2–4; interradial spines stout, subsacciform, pointed, in webbed tufts.
Figure 2. Abactinal view of holotypes of species of
Ailsastra
gen. nov.
(photographed at same magnification). a,
Ailsastra achituvi
sp. nov.
, R = 10 mm, NHM 1951.5.7.12; b,
Ailsastra amezianeae
sp. nov.
, R = 10 mm, MNHN EcAs 11845; c,
Ailsastra booneni
sp. nov.
, R = 9 mm, UF 1938; d,
Ailsastra eleaumei
sp. nov.
, R = 7.5 mm, MNHN EcAs 11843; e,
Ailsastra heteractis
(H.L.
Clark, 1938
)
, R = 7 mm, MCZ 3258; f,
Ailsastra paulayi
sp. nov.
, R = 16 mm, UF 1815.
Figure 3. Actinal view of holotypes of species of
Ailsastra
gen. nov.
a,
Ailsastra achituvi
sp. nov.
, R = 10 mm, NHM 1951.5.7.12; b,
Ailsastra amezianeae
sp. nov.
, R = 10 mm, MNHN EcAs 11845; c,
Ailsastra booneni
sp. nov.
, R = 9 mm, UF 1938; d,
Ailsastra eleaumei
sp. nov.
, R = 7.5 mm, MNHN EcAs 11843; e,
Ailsastra heteractis
(H.L.
Clark, 1938
)
, R = 7 mm, MCZ 3258; f,
Ailsastra paulayi
sp. nov.
, R = 16 mm, UF 1815.
Figure 4. a–c,
Ailsastra achituvi
sp. nov.
, NHM 1951.5.7.12: a, low carinal series of plates; b, abactinal spinelets, glassy convexities on plates; c, small oral plates. d–f,
Ailsastra amezianeae
sp. nov.
: d, abactinal interradial plates removed to show absence of superambulacral (arrow) and superactinal plates (paratype, MNHN EcAs 11846); e, abactinal spinelets (holotype, MNHN EcAs 11845); f, small oral plates (paratype, MNHN EcAs 11846). g–i,
Ailsastra booneni
sp. nov.
, UF 1938: g, two proximal carinal plates with longitudinal series of spinelets (arrows), breaks in enveloping integument which obscures plates, abactinal spinelets; h, distal interradius, inferomarginal spinelets, absence of superomarginal spinelets; i, small oral plates, proximal interradial single pyramidal spines.
Distribution
. NW
Madagascar
, Nossi Be.
Etymology
. Named in recognition of Dr Nadia Améziane of the Muséum National d’Histoire Naturelle, Paris, who has graciously assisted the authors with information and the loan of materials for echinoderm research.
Remarks
. The carinal plate arrangement, oral structure, and absence of superambulacral and superactinal plates, are consistent with this unique asterinid combination in the
Ailsastra
type
species
A. paulayi
. Molecular data are not available for
A. amezianeae
.