Tanaidacea (Crustacea: Peracarida) from Japan. I. Apseudomorpha from the East China Sea, Seto Inland Sea, and Nansei Islands
Author
Larsen, Kim
Author
Shimomura, Michitaka
text
Zootaxa
2006
1341
29
48
journal article
10.5281/zenodo.174415
b31cdd62-f249-470a-8207-03d41bef883d
11755326
174415
Androgynella nipponicus
(
Shiino, 1937
)
Apseudes nipponicus
Shiino, 1937
Material examined
1 female
(
NSMT
Cru R 245),
1 female
(
NSMT
Cru R 246),
4 females
(
NSMT
Cru R 245),
13 females
(
NSMT
Cru R 245), all from Sagami Bay, depth
13 m
.
18 August 1936
.
Remarks
Shiino (1937)
described
Apseudes
(now
Androgynella
Gutu, 2006
)
nipponicus
from Sagami Bay.
Lang (1953)
described
A. hermaphroditicus
from
Antarctica
and noted the morphological similarity between his new species and
A. nipponicus
.
Lang considered
A. hermaphroditicus
separate from
A. nipponicus
owing to differences in the rostrum, eyelobes and pleonal epimera (
Lang 1953:349
). Later,
Shiino (1970)
found similarlooking specimens from Tierra del Fuego,
Argentina
. He considered these to be conspecific to those found by Lang and that both species were a form of
A. nipponicus
and thus stated a bipolar distribution for this species. However,
Lang (1958:536)
had already synonymized
A. hermaphroditicus
with
A. spectabilis
(
Studer, 1883
)
from the Kerguelen Islands (subantarctic Indian Ocean). It followed that
A. nipponicus
also must be a synonym of
A. spectabilis
,
as finally stated by
Lang (1973)
, although no direct comparison was ever made between
A. nipponicus
and
A. spectabilis
.
As bipolar distributions of nonswimming peracarids are highly unlikely (see
Larsen 2005
) a closer examination of the
type
specimens was initiated. Also
Gutu (2006:76)
found this distribution suspect but refrained from reerecting
A. nipponicus
due to lack of morphological evidence. The present study (based on reexamination of the
types
) reveals that
A. nipponicus
and
A. spectabilis
are separate species. The presence of a small but clearly visible ventral spine on the rostrum of
A. nipponicus
(
which is not present in
A. spectabilis
), justify the resurrection of
A. nipponicus
.
The eyelobes and epimera characters mentioned by
Lang (1953:349)
are less distinct characters and could be attributed to variation or angle of observation. The situation is somewhat complicated by the fact that the material of Shiino’s
A. nipponicus
forma
hermaphroditicus
could not be located and the
type
material of
A. hermaphroditicus
(SMNH no. 413–421) appears to be lost (K. Sindemark, pers comm.). Judging from Lang’s (1953) illustrations
A. hermaphroditicus
could very well be a synonym of
A. spectabilis
as stated by
Lang (1958)
while
A. nipponicus
represents a separate species. Examination of the good illustrations of Shiino’s
A. nipponicus
forma
hermaphroditicus
(
Shiino 1937
:112, figs. 27a, 30f), suggests that the rostrum does not resembles that of
A. nipponicus
sensu
stricto
from the
type
locality, and neither does the shape of the female cheliped carpus. This means that
A. nipponicus
forma
hermaphroditicus
and
A. hermaphroditicus
might well be conspecific and might be conspecific with
A. spectabilis
,
but neither of them is conspecific with the original
A. nipponicus
.
When considering that
A. spectabilis
has a
type
locality off Kerguelen Island (Subantarctic), quite remote and different in habitat, to that of
A. nipponicus
, the distribution patterns also support the separation of these species. The
type
locality of
A. nipponicus
forma
hermaphroditicus
and
A. hermaphroditicus
is also
Antarctic
. We thus find sufficient evidence to remove the name
A. nipponicus
from
A. spectabilis
and the species
A. nipponicus
is here reerected (see also below).