New Lysianassoid Amphipods from the North Eastern Atlantic Ocean
Author
Kaim-Malka, R. A.
text
Zootaxa
2014
3821
5
551
566
journal article
45383
10.11646/zootaxa.3821.5.3
d03f0501-3ec5-4a54-ad9f-fd87639e48c5
1175-5326
229524
A1E6A9F9-23E1-4086-92CE-0F7FC509725A
Ambasia anophthalma
n. sp.
(
Figs 2–6
)
Type
material.
HOLOTYPE
. Adult female, with
5 eggs
,
11.88 mm
. Collected in the North Eastern Atlantic Ocean (Bay of Biscay) on
23 August 2002
. Cruise
VITAL
on R/V "L'Atalante" (
IFREMER
). Meriadzek Terrace (
Fig.1
). Depth:
1460 m
,
47° 36' N
;
8° 25' W
.
Holotype
deposited in the Muséum National d'Histoire Naturelle (Paris) N°: MNHN-IU-2013-11265.
FIGURE 1.
The Bay of Biscay with the position of the stations where the new amphipods species were collected. M: Meriadzek Terrace; N: Saint Nazaire Terrace.
PARATYPES
.
1 specimen
collected with the
Holotype
, in the same station. Specimen deposited in the Muséum National d'Histoire Naturelle (Paris) N°: MNHN-IU-2013-11266.—
1 specimen
collected on
26–28 August 2002
. Cruise
VITAL
on R/V "L'Atalante" (
IFREMER
). Saint Nazaire Terrace (
Fig.1
). Depth:
1550 m
,
46°15'N
,
4°43'W
. Specimen deposited in the Muséum National d'Histoire Naturelle (Paris) N°: MNHN-IU-2013- 11267.
Male unknown.
Etymology.
The name species refers to the absence of eyes (blind species).
Diagnosis.
Blind species. Head: lateral cephalic lobe triangular shaped. Maxilla 1: inner plate with one long apical seta. Gnathopod 2: propodus minutely chelate. Coxa 5 greatly sized. Epimeral plate 3 roughly quadrate, anterior and posterior margins slightly convex, distal margin straight and the posterodistal corner rounded. Urosome carina high and triangular shaped.
Description.
HOLOTYPE
. Adult female,
11.88 mm
(
Fig. 2
).
Head:
without eyes, blind species. Lateral cephalic lobe triangular and rounded distally. Epistome not prominent (
Figs. 2
; 3A, F).
Antenna 1:
shorter than antenna 2. Peduncular article1 expanded; articles 2 and 3 short. Flagellum 6 articulated, callynophore strong 2- fields. No calceoli. Accessory flagellum with 4 articles (
Figs. 2
; 3A, B).
Antenna 2:
broad, a little longer than antenna1; peduncular article1 comma shaped, very characteristic: the posterior part is rounded when the anterior one is triangular cut straight at the extremity; all of the other articles are rectangular (article 5 <article 4 <article 2 <article 3); flagellum with 7 articles. Except article 1 and 2, each article bears some setae (
Figs. 2
; 3A, C).
Mandible
(
Fig. 4
C, D, E): strong; molar absent, lacinia mobilis vestigial; palp elongated with setae on the distal part of article 2 and on article 3.
Maxilla 1
(
Fig. 3
D, E): inner plate very small bearing one long apical seta; outer plate longer with 6 apical spines; last palp article with 4 little apical strong teeth and 2 setae.
Maxilla 2
(
Fig. 4
F): the two plates are densely setose on their apical part.
Maxilliped
(
Fig. 4
A, B): palp scarcely exceeding outer plate, plates and palp very weakly setose, dactylus vestigial.
FIGURE 2.
Ambasia anophthalma
n. sp.
, holotype female. Scale 2 mm.
Pereon.
Gnathopod 1
(
Fig. 4
G): distal margin of the coxa 1 narrow and rounded, basis broad and long, carpus and propodus of same length, dactylus simple. All the articles are ornamented with setae.
Gnathopod 2
(
Fig. 5
A, B, C): coxa 2 roughly rectangular shaped, without setae, distal margin slightly expanded and rounded. Basis very long and narrow. Ischium subequal in length to carpus. Carpus-propodus joint constricted. Propodus oval / rectangular with long setae on the midanterior part, minutely chelate (
Fig. 5
B, C).
Pereopod 3
(
Fig. 4
H): coxa 3 rectangular shaped, sized large, distal margin slightly convex, without setae, covering a great part of coxa 2. The different articles slender, poorly setose. Basis longer. Basis> merus = propodus> carpus> ischium. Dactylus simple.
Pereopod 4
(
Fig. 5
D): coxa 4 sized large and partly covering coxa 3, posterior concavity more than half length of the coxa. The different articles slender and poorly setose. Basis> merus> propodus> carpus> ischium. Dactylus simple.
Pereopod 5
(
Fig. 5
E): smaller than pereopods 6 and 7. Coxa 5 square and sized large. Basis roughly oval shaped. The other articles are slender and ornamented with very little setae and spines. Merus with a posterior lobe. Dactylus simple.
Pereopod 6
(
Fig. 5
F): coxa 6 square shaped, smaller than coxa 5 and partly covered by it. Basis roughly rectangular shaped, length =1.6 width, posterior margin rounded. The other articles are slender and ornamented with very little setae and spines. Merus with a small posterior lobe. Dactylus simple.
Pereopod 7
(
Fig. 5
G): coxa 7 roughly square shaped, smaller than coxa 6 and partly covered by it. Basis with a large lobe, length =1.25 width, posterior margin rounded. The other articles are slender and ornamented with very little setae and spines. Merus with a small posterior lobe. Dactylus simple.
Pleon
Epimeral plate 1
(
Fig. 6
A): anterior margin slightly concave shaped, anteroventral corner round, posterior margin rounded, inferior margin straight.
Epimeral plate 2
(
Fig. 6
B): anterior margin rounded, inferior and posterior margins straight, posteroventral corner subquadrate.
Epimeral plate 3
(
Fig. 6
C): roughly quadrate, anterior and posterior margins slightly convex, ventral margin straight and the posteroventral corner rounded.
Urosome.
The carina is high and triangular shaped (
Fig. 2
).
Uropod 1
(
Fig. 6
D): long, peduncle and rami approximately of same length. External ramus very slightly longer than the inner one. Many little spines on peduncle and rami.
Uropod 2
(
Fig. 6
E): shorter than Uropod 1, U1 / U2 = 1.42. Peduncle as long as rami. Rami of equal length. Many little spines on peduncle and rami.
Uropod 3
(
Fig. 6
F): Short, U1> U2> U3; U2 / U3 = 3. 54; Peduncle stout. Rami of inequal length; inner ramus / outer ramus = 0.75; inner ramus lanceolate and one articulate, length subequal to the first article of the outer ramus; outer ramus 2-articulate, the first article is strong with little spines on the outer margin; the second article is in fact a strong tooth.
Telson
(
Fig. 6
G): triangular (length = 0.62 width); cleft on 2/3 of the length, one spine on the apical part of each lobe.
FIGURE 3.
Ambasia anophthalma
n. sp.
, holotype female. A: Head with antennae; B: Antenna 1; C: Antenna 2; D: Maxilla 1; E: Maxilla 1, enlargement of the apical part of the palp. F: Epistome and Labrum. Scales: E: 0.1 mm; B, C, D, F: 0.5 mm; A: 1 mm.
Discussion.
The genus
Ambasia
was created by
Boeck (1871)
and included only one species:
Ambasia atlantica
(Milne
Edwards, 1830
)
. The present work permits the addition of a new species,
Ambasia anophthalma
,
to this genus. The main differences between these two species are:
Ambasia anophthalma
is a blind species,
Ambasia atlantica
has a subsigmoid eye. Maxilla 1: inner plate with one long apical seta (
A. anophthalma
), two short setae (
A. atlantica
). Gnathopod 2: propodus oval/rectangular shaped (
A. anophthalma
); oval (
A. atlantica
). Epimeral plate 3: posteroventral corner rounded (
A. anophthalma
); producing a little tooth (
A. atlantica
). Urosome carina high and triangular shaped (
A. anophthalma
); high and roughly rectangular shaped (
A. atlantica
).