Six species of Axiidea and Gebiidea from the Indo-West Pacific (Crustacea, Decapoda)
Author
Ngoc-Ho, Nguyen
MusÉum national d’Histoire naturelle, DÉpartement Milieux et Peuplements aquatiques, case postale 53, 57 rue Cuvier, F- 75231 Paris cedex 05 (France) nngoc-ho @ mnhn. fr
ho@mnhn.fr
text
Zoosystema
2014
2014-09-26
36
3
545
561
http://dx.doi.org/10.5252/z2014n3a1
journal article
10.5252/z2014n3a1
1638-9387
5159175
Axianassa ngochoae
Anker, 2010
(
Fig. 5
)
MATERIAL EXAMINED
. —
Vietnam
.
Cân gio, HochiMinh city,
4-7 m
, Nguyên van Xuân coll.,
III.1998
:
1 ♂
, cl
7 mm
, tl
20 mm
(
MNHN
Th 1571).
DESCRIPTION
Carapace (
Fig. 5A
) rounded dorsally, with
linea thalassinica
well defined but cervical groove faint.
FIG. 5. —
Axianassa ngochoae
Anker, 2010
, ♂, tl 20 mm (MNHN Th1571):
A
, lateral view;
B
, anterior part of carapace;
C
, telson and uropod;
D
,
E
, pereopod 1 and 2. Scale bars: 1 mm.
Rostrum (
Fig. 5B
) unarmed, anteriorly rounded, slightly surpassing cornea of eyes.
Pleomere 1 (
Fig. 5A
) about half dorsal length of somite 2, pleuron tapering ventrally to a spiniform process; pleomeeres 2 and 3 subequal in length, pleomeres 4-6 shorter, pleura poorly defined in all, unarmed.Telson (
Fig. 5C
) with greatest width about one-third of middorsal length, posterior margin rounded not clearly separated from lateral margins.
Cornea terminal, pigmentation partly lost after preservation. Antennular peduncle (
Fig. 5A
) about half length of antennal peduncle; antennular articles 1 and 2 about 1/3 length of article 3, latter slender, elongate-cylindrical, lower flagellum with faintly differentiated articles, superior flagellum of about 30 articles, just reaching distal margin of antennal article 4. Antennal acicle (
Fig. 5B
) elongate with pointed tip, antennal article 4 elongate, cylindrical, flagellum about twice as long as peduncle.
Pereopod 1 (
Fig. 5A, D
) asymmetrical but similar in spinulation; both ischium and merus with one spine near anterior third of lower border; carpus and palm unarmed, fixed finger about as long as palm in minor pereopod 1, three-thirds as long as palm in major pereopod 1, cutting edge with small rounded teeth and a larger one near midlength. Dactylus about as long as fixed finger, with curved tip, a flat tooth on proximal third, a large round tooth near midlength and four or five smaller round teeth distally. Pereopod 2 (
Fig. 5A, E
) ischium unarmed, merus bearing about 22-24 stout setae on lower border, carpus and propodus with stiff setae on lower border and fine setae on upper border; dactylus about half as long as propodus, slender with fine setae on upper and lower border. Pereopod 3 (
Fig. 5A
) with setae on lower border of propodus, dactylus with pointed tip with five or six corneous spinules on upper border. Pereopods 4, both right and left missing. Pereopod 5 (
Fig. 1A
) flexed distally with lower border of propodus becoming dorsal bearing numerous setae; numerous short setae on lower border of dactylus.
Pleopod 1 absent. Pleopods 2-5 (
Fig. 5A
) biramous, rami lanceolate. Uropods with both exopod and endopod (
Fig. 5C
) ovate, unarmed.
REMARKS
The specimen studied is a young male with no pleopod 1 and small gonopores on the coxae of pereopod 5.
Nine species of
Axianassa
are known to date with six of them originating from the vicinity of the American continent:
A. arenaria
Kensley & Heard, 1990
(Gulf of Mexico),
A. canalis
Kensley & Heard, 1990
(
Panama
canal),
A. intermedia
Schmitt, 1924 (
Curaçao
)
,
A. jamaicensis
Kensley & Heard, 1990
(
Jamaica
)
,
A. mineri
Boone, 1931
(Bay of
Panama
),
A
.
australis
Rodrigues & Shimizu, 1992 (
Brazil
)
. Except for
A. mineri
, the other species are from western Atlantic. The first five species were either established or redescribed by
Kensley &
Heard
(1990)
.
Three species recently described are from southwestern Pacific:
A. sinica
W. Liu & R. L.
Liu, 2010
from South
China
Sea,
A. ngochoae
Anker, 2010
from Polynesia,
Axianassa heardi
Anker, 2011
from off
Queensland
,
Australia
.
Of these last three species,
A. sinica
has a pointed rostrum (see
Liu & Liu 2010
: fig. 2A) while in
A. ngochoae
and
A. heardi
, the rostrum is obtuse (
Anker 2010
: fig. 1C, D; 2011: fig. 9B, E). It is unarmed in
A. ngochoae
but bears teeth on lateral margins in
A. heardi
.
The specimen from
Vietnam
agrees with the
type
except for the pereopod 2 (
Fig. 5E
) that is provided with stout setae on the lower border of the merus.
Family
UPOGEBIIDAE Borradaile, 1903