A new species of Ledoyerella, L. kunensis sp. nov. (Amphipoda, Senticaudata, Kamakidae) from South West Africa
Author
Zettler, Michael L.
Author
Myers, Alan
text
Zootaxa
2018
2018-07-23
4450
1
142
150
journal article
29326
10.11646/zootaxa.4450.1.11
27637276-6ce8-4b6c-8688-36d04bb47616
1175-5326
1444560
AD9D63C6-6E26-4157-8BD5-9FBE46176B11
Ledoyerella kunensis
sp. nov.
(
Figs 1–5
)
Type
material.
Holotype
: one male,
6.7 mm
(
ZMB
31313) (
Stn. BE
2;
Namibia
,
Skeleton Coast
; water depth
32 m
; grab sampling;
18.191°S
;
11.841°E
; salinity at bottom 35.4 psu, temperature at bottom 14.3°C, oxygen 1.46 ml/l, collected
12 May 2004
)
.
Paratype
: one female,
5.5 mm
(
ZMB
31314) (data same as holotype)
.
Non-type material (
ZMB
31315) (
Stn. BE
1;
Namibia
, Skeleton Coast; water depth
42 m
; grab sampling;
18.385°S
;
11.922°E
; salinity
at bottom 35.3 psu, temperature at bottom 13.4°C, oxygen 0.12 ml/l, collected
12 May 2004
). Additional material, see
Table 1
.
TABLE 1.
Sampling sites of
Ledoyerella kunensis
sp. nov.
along the Angolan and Namibian coast from North to South. (*=type locality)
Station |
Country |
Latitude (S) |
Longitude (E) |
Depth (m) |
T°C |
Date of sampling |
Number of specimens |
Be71 |
Angola |
9.435 |
12.831 |
102 |
15.3 |
0 2 August 2011 |
2 |
Be65 |
Angola |
9.435 |
12.999 |
42 |
16.0 |
0 2 August 2011 |
52 |
SU4 |
Angola |
10.490 |
13.423 |
60 |
15.7 |
0 1 August 2011 |
4 |
SU5 |
Angola |
10.508 |
13.577 |
28 |
17.1 |
0 1 August 2011 |
31 |
45 |
Angola |
12.088 |
13.701 |
19 |
18.1 |
23 May 2004 |
2 |
LO4 |
Angola |
12.338 |
13.439 |
92 |
15.1 |
31 July 2011 |
1 |
BM5 |
Angola |
13.991 |
12.362 |
48 |
16.5 |
31 July 2011 |
1 |
Na5 |
Angola |
15.096 |
12.105 |
62 |
16.1 |
30 July 2011 |
5 |
BE2* |
Namibia |
18.191 |
11.841 |
32 |
14.3 |
12 May 2004 |
39 |
BE1 |
Namibia |
18.385 |
11.922 |
42 |
13.4 |
12 May 2004 |
82 |
Nam005 |
Namibia |
20.223 |
12.629 |
154 |
12.5 |
24 August 2011 |
3 |
Nam006 |
Namibia |
20.281 |
12.560 |
204 |
11.9 |
24 August 2011 |
8 |
Type
locality.
Namibia
(Province
Kunene
) about
100 km
south of the River
Kunene
mouth, off the Skeleton Coast in
32 m
water depth.
Etymology.
Named for the River
Kunene
at the border between
Angola
and
Namibia
in the waters off which the material was collected.
Description
. Based on male
holotype
,
6.7 mm
.
FIGURE 1.
Ledoyerella kunensis
sp. nov.
, lateral view of holotype male (6.7 mm).
Head
,
Head
ocular lobes extended forward; eye oval, of medium size, almost entirely situated in the ocular lobe; anteroventral margin deeply excavated.
Antenna 1
scarcely more than one third body length; peduncular articles
1–3 in
the length ratios 1:1:0.6; flagellum about two thirds length of peduncle with 12 articles; accessory flagellum with two long articles and a rudimentary terminal article.
Antenna 2
longer than antenna 1; peduncular articles 4 and 5 subequal in length; flagellum only a little longer than the combined length of peduncular articles 4 and 5, with 19 articles.
Labrum
without epistome.
Mandible
molar of moderate size, triturative; left lacinia mobilis 4-dentate, right lacinia mobilis 3-dentate; palp article 2 longer than article 3; article 3 subovate with long mostly distal and subdistal setae.
Maxilla 1
inner plate with two unequal distal setae and many fine setae along medial margin.
Maxilla 2
lacking oblique setal row.
Labium
mandibular projections blunt.
Maxilliped
palp article 2 about twice as long as broad, article 4 about two thirds length of article 3.
FIGURE 2.
Ledoyerella kunensis
sp. nov.
, antennae and mouthparts of holotype male.
FIGURE 3.
Ledoyerella kunensis
sp. nov.
, gnathopods, coxal plates, epimeral plates and pereopods 3 and 4 of holotype male.
FIGURE 4.
Ledoyerella kunensis
sp. nov.
, pereopods 5 to 7, uropods and telson of holotype male.
Pereon
. Sternal processes absent.
Gnathopod
1 coxa anteriorly produced, rounded; basis immensely swollen, posterodistal margin with three groups of long setae; carpus enlarged, subovoid, two thirds as broad as long; propodus about two thirds length of carpus, the posterior margin weakly crenulate, palm produced forward anterodistally into rounded lobe; dactylus stout, posterior margin with spines, overlapping palm.
Gnathopod 2
coxa larger than that of gnathopod 1, deeper than broad, a little less deep that coxa 3; basis immensely swollen, anterior margin weakly concave distally; carpus parallel-sided; propodus about two thirds length of carpus, posterodistal margin produced into stout, parallel-sided round ending projection; palm irregular with shallow sinus, and thick, distally rounded, subproximal robust seta; dactylus stout, overlapping palm.
Pereopods 3–4
slender, dactylus about half length of propodus.
Pereopods
5–7
in the length ratios 1:1.4:1.7; basis only weakly expanded.
FIGURE 5.
Ledoyerella kunensis
sp. nov.
, gnathopods and pereopod 3 of paratype female (5.5 mm).
Pleon
.
Epimeral plates 1–3
rounded.
Uropod 1
peduncle longer than rami with strong distal inter-ramal spine; inner ramus longer than outer.
Uropod 2
peduncle subequal in length with outer ramus, inner ramus longer than outer.
Uropod 3
rami longer than peduncle, outer ramus with small second article, both rami with distal robust setae, lacking slender setae.
Telson
with each lobe bearing a strong robust seta.
Female
(sexually dimorphic characters).
Gnathopod
1 slender; basis parallel-sided, nearly three times as long as broad; carpus longer than propodus; propodus palm very oblique, with subproximal robust seta; dactylus fitting palm.
Gnathopod 2
basis slender, parallel-sided about twice as long as broad; carpus and propodus stout, subequal in length, palm oblique, with subproximal robust seta; dactylus slightly overlapping palm.
Habitat.
This new species occurred in water depths between 19 and
204 m
on sandy and muddy sediments often with shell debris. The salinity ranged between 35.3 and 35.7 psu, the oxygen content in bottom water varied between 0.12 and 2.3 ml/l. The co-occurring temperatures were between 13 and 17°C.
Distribution.
Currently known only from the coasts of
Angola
and
Namibia
.
Remarks.
Ledoyerella kunensis
sp. nov.
is most similar to
L. caputphotis
, but differs in the form of the male gnathopods. In
L. kunensis
sp. nov.
gnathopod 1 has a short propodus with palmar lobe, whereas in
L. caputphotis
the propodus is long, with an oblique palm. The gnathopod 2 has a slender propodus with strong forward projecting palmar spine in
L. kunensis
sp. nov.
, whereas
in
L. caputphotis
the propodus is broad, with a weak, short palmar spine. In
L kunensi
s
sp. nov.
, antenna 1 is shorter than antenna 2 (longer than antenna
2 in
L. caputphotis
), In addition the uropod 2 peduncle of
L. caputphotis
bears a long distal inter-ramal spine, lacking in
L. kunensis
sp. nov.
and
L. caputphotis
has long slender terminal setae on the outer ramus of uropod 3 that are absent in
L. kunensis
sp. nov.