Japanese Pseudosmittia Edwards (Diptera: Chironomidae)
Author
Saether, Ole A.
text
Zootaxa
2006
2006-05-11
1198
21
51
journal article
27018
10.5281/zenodo.2646335
dc89386b-3791-4ac2-948a-73f69552b3a9
1175-5326
2646335
B6AA9775-7CF1-4A11-BCDF-BA927FDCCD85
Pseudosmittia littoralis
(Tokunaga)
(
Figs. 10, 11
)
Spaniotoma (Smittia) littoralis
Tokunaga, 1936
: 303
.
Smittia (Pseudosmittia) littoralis
(Tokunaga)
;
Goetghebuer (1940
–1950: 107).
Pseudosmittia littoralis
(Tokunaga)
;
Yamamoto (2004: 89)
.
Type material
JAPAN
:
Holotype
lost,
paratypes
Wakayama Prefecture
,
Seto
,
5.vii.1934
and
Mie Prefecture
,
Ukijama
,
6.viii.1934
,
M. Tokunaga
(
KU
) (not examined).
Diagnostic characters
The male imago can be separated from other members of the genus by the combination of a strong apical seta on the antenna and an inferior volsella more triangular than in
Pseudosmittia xanthostola
(Kieffer)
and
P. brevifurcata
(Edwards)
. According to
Tokunaga (1936: plate viii, fig. 5)
it also may have an accessory lobe of the inferior volsella.
Description
Male. No
type
material was available for loan, but the description by
Tokunaga (1936)
is reasonably complete. He gives the total length as about
1.2 mm
and the coloration as dull black with brownish black abdomen, antennal ratio as 0.5–0.8 (0.6), temporals apparently consisting of outer verticals only, clypeus with 6 or 7 setae, and relative lengths of four last palpomeres as 6:15:17:28.
The median antepronotal lobes are reduced medially, with 2 lateral antepronotal setae; dorsocentrals probably relatively numerous since they are biserial in front; prealars 6–7; scutellum with 6 setae.
The wing as illustrated by
Tokunaga (1936: fig. 1)
is shown in
Fig. 10
. The VR
1
is about 1.65, VR
2
about 1.25, anal lobe obtuse, costa not extended and Cu
1
slightly sinuous.
The middle tibia carries only one apical spur, the hind tibial comb consists of 12–14 setae. The relative lengths of the leg segments (fe to ta
5
) are as follows:
Fore leg: 19.5: 19.5: 13.5: 7: 4.5: 3: 3.
Mid leg: 20: 20: 11: 6: 4.5: 3: 3.
Hind leg: 22: 22: 14: 7: 7: 3: 3.
The hypopygium as illustrated by
Tokunaga (1936: fig. 5)
is reproduced in
Fig. 11
. The anal point is triangular with straight sides, pointed, and apparently with about 20 lateral setae. The phallapodeme, sternapodeme and virga are unknown. The inferior volsella is placed posterior on the gonocoxite, and apparently with an accessory lobe.
Female, pupa and larva: The female is inadequately described by
Tokunaga (1936)
. However, according to
Tokunaga (1964: 520)
the gonocoxite has hornlike posterior extensions, i.e. similar to
P. guamensis
(
Tokunaga) (Tokunaga 1964
: fig. 7e
). The pupa and larva are unknown.
Ecology and distribution
According to
Tokunaga (1936: 303)
the species was swarming in the evening on a gravelly seashore, about
10 cm
above the ground and usually above the zone of the hightide mark. The species is known only from the Pacific coast of Kii Peninsula, Honshu,
Japan
.
Pseudosmittia mathildae
Albu
(
Fig. 12
)
?
Pseudosmittia
sp. B
Strenzke (1950: 309)
.
Pseudosmittia mathildae
Albu, 1968
: 4
.
Pseudosmittia itachibifurca
Sasa
et
Kawai, 1987
: 54
;
Yamamoto (2004: 87)
. Syn. n.
Pseudosmittia amamibifurca
Sasa, 1990a
: 132
;
Saether and Ferrington (2003: 3)
;
Yamamoto (2004:
87) as syn. of
P. itachibifurca
.
Pseudosmittia trilobata
(
Edwards, 1929: 364
)
;
Langton, (1991
: 173
), pro parte, misidentification.
Pseudosmittia furudobifurca
Sasa
et
Arakawa, 1994
: 100
;
Yamamoto (2004: 88)
as syn of
P.
itachibifurca
. Syn. n.
Pseudosmittia hibaribifurca
Sasa, 1993: 80
;
Yamamoto (2004: 88)
as syn of
P. itachibifurca
. Syn.
n.
Pseudosmittia (Nikismittia) shofukuundecima
Sasa, 1998a
: 42
;
Yamamoto (2004: 88)
as syn of
P.
itachibifurca
. Syn. n.
Diplosmittia amamibifurca
(Sasa)
; Saether
et al.
(2000: 185).
Diplosmittia furudobifurca
(Sasa
et
Arakawa)
;
Saether
et al.
(2000
: 185
).
Diplosmittia hibarabifurca
(Sasa) Saether
et al.
(2000: 185)
.
Diplosmittia itachibifurca
(Sasa)
; Saether
et al.
(2000: 185).
Diplosmittia shofukuundecima
(Sasa)
; Saether
et al.
(2000: 185).
Material examined
JAPAN
:
Honshu
,
Toyama
Pref.,
Itachigawa River
,
holotype
♂
of
P. itachibifurca
,
16.iv.1986
,
S. Nagai
et al.
(
NMST
,
No. A
115: 03); Honshu,
Toyama
Pref.,
Lake Furudo
,
holotype
♂
of
P. furudobifurca
,
23.viii.1993
,
M. Sasa
&
R. Arakawa
(
NMST
,
No. A
248: 37); Honshu,
Toyama
Pref., Kurobe,
holotype
♂
of
P. shoufukuundecima
,
30.iv.1996
,
M. Sasa
(
NMST
, No. 326: 50); Honshu,
Fukushima
Pref.,
Lake Hibara
,
holotype
♂
of
P. hibarabifurca
,
8.vi.1991
,
M. Sasa
(
NMST
,
No. A
223: 90); Nansei Archipelago,
Kagoshima
Pref.,
AmamiOshima Is.
,
Yakkachei River
,
holotype
and
paratypes
♂
of
P. amamibifurca
,
18.iii.1989
,
M. Sasa
&
S. Hattori
(
NMST
,
holotype
:
No. A
179: 21,
paratypes
:
Nos
179: 22–27).
Material
from
China
,
Germany
,
Italy
, and
USA
also has been examined.
Diagnostic characters
Antenna without apical strong seta. Antepronotal lobes reduced medially, 2 acrostichals, no supraalars. Postcubitus not forked, R
4+5
ending well proximal to apex of M
3+4
. Anal point small and triangular, superior volsella absent, inferior volsella with accessory lobe placed well posterior on gonocoxite, gonostylus bilobed. Female without posterolateral projection on gonocoxite, tergite IX divided by median line only, seminal capsule ovoid and relatively dark. Pupa with stronger anterior and posterior shagreen on tergites, with nose on wing sheath, without setae on anal segment, tergite IX with longitudinal ridge carrying 2–3 rows of strong points, genital sac with spinules in both sexes. Larvae with 3 inner teeth on mandible, 4 pairs of lateral teeth on mentum; posterior parapods with 8 claws,
15–18 m
long; antennal blade longer than basal segment, about as long as the latter is wide.
Description
All stages of the species will be redescribed in a worldwide revision of
Pseudosmittia
(in prep.).
FIGURES 10–13.
Pseudosmittia
spp., male imagines. 10–11.
P.
littoralis
(Tokunaga)
, wing (10), hypopygium (11), both from Tokunaga (1936). 12.
P.
mathildae
Albu
(holotype of
P.
amamibifurca
Sasa
), hypopygium. 13.
P. nishiharaensis
Sasa
et
Hasegawa
(holotype), hypopygium.
Remarks
Pseudosmittia itachibifurca
may represent a different species since the AR was described as 0.64–0.84 and the gonostylus as lacking a megaseta. However, nonJapanese specimens show an AR of 0.42–0.60, and a variation of 0.29–0.84 is not unusual in other species of
Pseudosmittia
.
As shown by
Yamamoto (2004: 88)
the megaseta is present.
Pseudosmittia amamibifurca
could be regarded as a subspecies since the AR is lower than in other populations and the
type
locality (Nansei Archipelago, in the Oceanic (Indo Pacific Region) represents the only record from outside the Holarctic Region.
Pseudosmittia mathildae
differs from most members of the genus in having a bifurcate gonostylus. For this reason, some past assignments on the basis of the male imago alone have resulted in generic misplacement (see the list of synonyms above). However, the immature stages show the species is an atypical member of
Pseudosmittia
.
Ecology and distribution
The larvae from the
USA
are from moist banks along rivers and streams and the larva mentioned by Strenzke as
Pseudosmittia
sp. B, which is most likely the larva of
P. mathildae
,
was collected from watersaturated peat in a bog. The species is known from
Austria
, southern
Germany
, northern
Italy
,
Romania
,
China
,
Japan
including the Nansei Archipelago, and in the
USA
from
Alabama
,
Georgia
and South Carolina. One of the samples from
China
,
Guangdong
, is from well within the Oriental Region.