The genus Microptila Ris (Trichoptera, Hydroptilidae) in Japan
Author
Ito, Tomiko
text
Zootaxa
2017
4232
1
104
112
journal article
36543
10.11646/zootaxa.4232.1.7
23068eb9-dd4a-4eb8-a613-10fe4bfba459
1175-5326
292743
7C3A4400-CCA5-4E9E-82BA-F8B931BC3F9B
Microptila genka
sp. nov.
(
Figs 2
,
4
B, 5)
Diagnosis
. The male of this species is similar to those of
Microptila orienthula
and the Vietnamese
M. dironga
Oláh and Johanson 2010
, but can be distinguished from these as follows: (1) Segment IX has a broader tegmental bridge (
cf
. the very narrow bridge in
M. orienthula
and
M. dironga
), with the dorsal midline about 1/5 as long as segment IX (
Fig. 2
B); (2) the subgenital plate is rounded caudally (
Figs. 2
B, 2D,
cf
. the plate has a tiny U- or Vshaped excavation caudally in
M. orienthula
); and (3) the inferior appendages are stout with thick setose ridges mesally (
Figs. 2
A, 2C, 2E,
cf
. the rather slender appendages in
M. dironga
). Females of this species are similar to those of
M. orienthula
, but can be distinguished from the latter by the presence of a triangular median process on the caudal margin of segment VII (
Fig. 2
G,
cf
. the caudal margin of segment VII is wholly convex in
M. orienthula
).
Male
. Length of each forewing and hind wing
1.6–1.7 mm
and
1.4–1.5 mm
, respectively (n = 3). Antennae each 19-segmented and
0.5–0.6 mm
long (n = 3).
Genitalia (
Figs. 2
A–2F). Segment IX (IX) annular, in dorsal view (
Fig. 2
B) excavation of anterior margin semi-circular, excavation of posterior margin broadly concave; transverse tegmental bridge broad, dorsal midline about 1/5 as long as segment IX; in ventral view (
Fig. 2
C) excavation of anterior margin broadly triangular, excavation of posterior margin wide and shallow. Tergite X (t X) semimembranous, transparent, with lightly sclerotized lateral and caudal margins, quadrate, with deep and wide triangular excavation caudally in dorsal view (
Fig. 2
B). Subgenital plate (sg plate) twice as long as tergite X, elongate ovate, rounded caudally, semimembranous with lightly sclerotized lateral margins (
Figs. 2
A, 2B, 2D). Inferior appendages (inf app) large, setose, without any branches; in ventral view (
Fig. 2
C) each with basal 2/3 stout, apical 1/3 slender, apex incurved and acute; in ventromesal view (
Fig. 2
E) basal 2/3 with longitudinal setose ridge mesally and apical 1/3 rectangular with strongly sclerotized ridge. Phallus long with slender, elongate titillator (ti) arising near apical 1/4, titillator encircling phallus 1.5 times (
Fig. 2
F).
Female
(
Fig. 2
). Length of each forewing and hind wing
1.6–1.8 mm
and
1.3–1.4 mm
, respectively (n = 4). Antennae each 19-segmented and
0.5–0.6 mm
long (n = 4).
Abdominal segments I–VII densely covered with long thick setae. Segment VII (VII) tergite and sternite fused laterally, caudal margin with triangular median process in ventral view (
Fig. 2
G). Segment VIII almost as long as segment VII, often withdrawn into segment VII.
Holotype
: male,
Japan
,
Ryukyu Islands
,
Okinawa-jima
,
Nago-shi
,
Genka
, hygropetric zone near
Hogenhashi
, 26˚36’16” N, 128˚04’29” E,
65 m
a.s.l.
,
8.iv.2011
,
T. Ito
(CBM-ZI 151359).
Paratypes
: 2 males, 1 female, same data as holotype (CBM-ZI 151360–151362).
Other
specimens examined
.
1 male
, same data as holotype
.
Japan
,
Ryukyu Islands
,
Ishigaki-jima
:
2 males
,
3 females
, hygropetric zone beside
Nagura-gawa
,
18.iii.2016
,
T. Ito
;
1 male
,
1 female
, unnamed waterfall beside foot path of
Mt. Omoto-dake
,
20.iii.2016
,
T. Ito.
Habitat
(
Fig. 4
B). Adults of this species were collected at hygropetric zones and waterfalls.
Etymology
. The specific name refers to the locality (
nakama
, a noun) where the
type
specimens were collected.
Distribution
(
Fig. 5
).
Japan
(Ryukyu Islands: Okinawa-jima, Ishigaki-jima).
Japanese name
. Genka-mikuro-himetobikera.