The stem-boring sawfly genus Cephus latreille (Hymenoptera: Cephidae) in Japan

6 Pages·2002·2.8 MB·

by  D R Smith

PROC. ENTOMOL. SOC. WASH.
104(2), 2002. pp. 479-484
THE STEM-BORING SAWFLY GENUS CEPHUS LATREILLE
(HYMENOPTERA: CEPHIDAE) IN JAPAN
David R. Smith and Akihiko Shinohara
(DRS) Systematic Entomology Laboratory, PSI, Agricultural Research Service. U.S.
Department of Agriculture, % National Museum of Natural History, Smithsonian Insti-
tution, Washington, DC 20560-0168, U.S.A. (e-mail: [email protected]); (AS)
Department of Zoology, National Science Museum (Natural History), 3-23-1 Hyakunin-
cho, Shinjuku-ku, Tokyo 169-0073, Japan (e-mail: [email protected])
—
Abstract. Two species of CepJnis occur in Japan, C hyalinatus Konow from Hokkaido
and C. brachycercus Thomson, newly recorded from Japan, from Honshu. Clarification
of past records of Cephus in Japan are presented. A key, descriptions, and illustrations of
the abdomen are given for both species.
Key Words: stem-borers, Cephidae, Cephus, Japan
Cephas is primarily a Eurasian genus of from Hokkaido (Takeuchi 1936) to Cephus
20 to 25 species, all ofwhich are associated hyalinatus. Takeuchi later recorded C. cani-
with grasses. Gussakovskij (1935) keyed tschatcalis from Kunashiri Island, but this
and discussed 23 Palearctic species, Benson is corrected to C. hyalinatus in this paper.
(1946) estimated 25 world species, and Mu- Togashi (1997, 1998) gave collection re-
che (1981) keyed and discussed 31 world cords of Cephus hyalinatus from Akan,
species. Two species occur in North Amer- Hokkaido, and Niigata Prefecture, Honshu,
ica, but one, Cephus pygmaeus (L.) is an respectively, but the latter was corrected to
introduction, and the other, Cephus cinctus Stenocephus oncogaster Shinohara by Shi-
Norton, is still open to question as to nohara (1999).
Specimens of this genus are not com-
whether it is native or an early introduction
monly collected in Japan, and only a few
from eastern Asia. Larvae bore and feed in
from Hokkaido and Honshu are represented
the stems of grasses and can be especially
in collections. Based on about 35 specimens
destructive in cultivated grain crops such as available, we record two species from Ja-
wheat.
pan, Cephus hyalinatus from Hokkaido and
Takeuchi (1938) recorded four species of Cephus brachycercus Thomson from Hon-
Cephus from northeastern Asia, but two of
C shu. The former is widespread in eastern
them, C. nigripennis Takeuchi and sach- Asia, and the latter is widespread in Eurasia
alinensis Takeuchi, are now placed in Cal- and is reported here for the first time from
ameuta Konow (Benson 1946). Ofthe other Japan. Based on the specimens available,
two, one, Cephus hyalinatus Konow, is there are rather constant color differences
known from eastern Asia including Japan between those collected in Honshu and
(Hokkaido), and the other, C. camtschat- those from Hokkaido. Thus, at present we
calis Enslin, from Kamtchatka and Sakha- prefer to treat them as separate species, and
lin. Takeuchi (1938) corrected his previous we attempt to clarify past records from Ja-
record of Cephus canitschatcalis Enslin pan.
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480 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON
Cephus belongs to the tribe Cephini, all Cephus hyalinatus Konow
of which are associated with grasses. It is (Figs. 1, 3)
separated from the other two genera of the Cephus hyalinatus Konow 1897: 173.
tribe, Calameuta and Trachelus, by the fol-
Takeuchi 1938: (Hokkaido).—Togashi
lowing: Distance between antennae sube-
1997: (Hokkaido).
qual to distance between antenna and ten- Cephus camtschatcalis: Takeuchi 1936:
torium; female sheath in dorsal view not —
59. Takeuchi 1955: 9 (misidentifica-
broadened toward apex; male eighth ster-
tions).
nite without concavity, with only a patch
and apical fringe of modified flattened se- This species was described from "Sibiria
tae. In Calameuta, the distance between the or. (Irkutsk)." It has been recorded from
antennae is much shorter than the distance various localities in eastern Russia (Gussa-
between the antenna and tentorium (as 1.0: kovskij 1935, Verzhutskii 1966), Kunashiri
C
1.5 to 2.0), and in Trachelus the female Island (Takeuchi 1955 [as camtschatcal-
sheath is broadened at its apex and the male is]), and Hokkaido, Japan (Takeuchi 1936
C
eighth sternite has a deep concavity with [as camt—schatcalis]), Takeuchi 1938).
modified setae. Female. Length, 9.0-11.0 mm. Anten-
na and head black; mandible yellow with
Key TO Japanese Species of Cephus
apex reddish brown; maxillary palpal seg-
\. Female 2 ments 3-6 yellow. Thorax black, some-
- Male 3 times extreme upper corner of mesepister-
2. sAebgdmoemntesn 3(F-i7g,. a1p)pweiatrhinlgatearlalmoysetllaoswaspoltatseroanl num with small yellow spot. Fore- and mid-
yellow longitudinal stripe, yellow transverse legs black with tibiae and tarsi yellow. Hind-
bands on posterior margins of abdominal seg- leg black with tibia yellow with about
ments 4 and 6, apex of9th tergite broadly yel- apical fourth black. Abdomen black with
low; wings commonly moderately infuscated segments 3-7 yellow laterally, yellow ex-
hyaliiiatits Konow
- Abdomen (Fig. 2) with lateral yellow spots on tending width of segments, thus appearing
segments 3 or 4-7, spots small and separated, as a lateral longitudinal stripe; transverse
not appearing as a lateral longitudinal stripe, yellow bands on posterior margins of seg-
without yellow transverse bands, though 6th ments 4 and 6; apex of 9th tergite broadly
segment sometimes with narrow incomplete yellow. Oblong plate (valvifer 2) yellow
band on posterior margin, 9th tergite narrowly
yellow at apex; wings hyaline ventrally. Wings moderately, uniformly in-
brocliycercus Thomson fuscated; costa and anterior margin of stig-
3. Abdomen (Fig. 3) with transverse yellow ma yellowish, rest of stigma and veins
bands on posterior margins of segments 3. 4, black. Antenna with 18 or 19 segments;
6, and 7, narrow or incomplete on 3 and 7, preapical segments slightly longer than
segments 3 or 4-7 with lateral yellow spots,
sometimes minute spots on 2 and 8; wings broad. Hindtibia with 2 preapical spines.
commonly moderately infuscated; venter of Tarsal claw with a minute inner tooth, much
cervical sclerite usually with yellow spot; me- shorter t—han outer tooth.
sepisternum with yellow spotonextremeupper Male. Length, 8.0-9.5 mm. Outer sur-
corner and yellow spot usually on lower ante- face ofantenna from segment 5 to apex yel-
rior area hyolimitus Konow
- Abdomen (Fig. 4) with transverse yellow lowish. Head black, usually with yellow
bands on posterior margins ofsegments 4 and spot on lower inner orbit near malar area
6, lateral yellow spots on segments 3 or 4-7; and spot on supraclypeal area bordering
wings hyaline; cervical sclerites and mesepis- clypeus; these spots sometimes small or ab-
ternum usually black except sometimes inner sent. Thorax black with yellow spot on ex-
ventral surface ofcervical sclerite with yellow
spot andpossibly a small yellow spotondorsal treme upper corner of mesepisternum; per-
corner of mesepisternum apterum yellow; yellow spot on lower an-
broclivcerciis Thomson terior mesepisternum, and yellow spot on
VOLUME 104, NUMBER 2 481
Figs. 1-4. Abdomen, lateral view. 1, Ceplutshyalinatus. female. 2, C brachycerciis, female. 3, C. hyalinatus,
male. 4, C. braclncerciis. male.
venter of cervical sclerite. Fore- and mid- with lateral yellow spots on segments 3 or
legs with coxae yellow anteriorly, black 4-7, sometimes minute spots on 2 and 8,
posteriorly; trochanters black; outside mar- spots separated; yellow transverse bands on
gin of femora black, inside margin of fem- posterior margins of segments 3, 4, 6, and
ora and tibiae and tarsi yellow; hindleg sim- 7, usually narrower on 3 and sometimes in-
ilar but black mainly at base of coxa with complete on 3 and 7. Apex of hypandrium
apical half or more yellow. Abdomen black and harpes of male genitalia yellow.
482 PROCEEDINGS OF THE ENTOMOLOGICAL SOCIETY OF WASHINGTON
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Japan records. Hokkaido: Wakkanai, C hyalinatus. Takeuchi (1955) recorded C
7-VII-1977, col. K. Baba (2 9,3 6); same camtschatcalis from Kunishiri Island. We
except 5-VII-1977 i\ S); Rishiri Is., 2-VII- have examined those specimens, deposited
1968, T. Naito leg. (2 9, 1 6); Kawayu, in Hokkaido University, Sapporo, and con-
25-VI-1969, T. Naito (Id); Teshio, 2-VII- firm that they are actually C. hyalinatus.
C
1930, Takeuchi (identified as hyalinatus Togashi's (1998) record of C. hyalinatus
by Takeuchi) (1 6). — from Honshu was erroneous and is actually
Other specimens examined. Russia, Sa- Stenocephus oncogaster (Shinohara 1999).
khalin: Konuma, 7-VII-1930 (identified as
C. hyalinatus by Takeuchi) (2 9); Karafuto Cephus brachycercus Thomson
(= Sakhalin), 1922, coll. M. Yano (''753" (Figs. 2, 4)
K. Sato Collection 1975) (2 9); Sakhalin, Cephus brachycercus Thomson 1871: 322.
Yuzhno-Sakhalinst City, meadows near for-
est stream, 15-V1-1971, V. Ermolenko (3 This species was described from Europe,
6)\ Sakhalin, Shenbunino Vil., meadow but it occurs across the Palearctic (Gussa-
along Japanese Sea, 19-VI-1971, V. Ermo- kovskij 1935, Verzhutskii 1966) and is here
lenko (1 9, 1 6). Russia, Primorski Kray, newly reco—rded from Honshu, Japan.
Primorskoe Vil., Reserve Kedzovaya Female. Length, 6.5-8.3 mm. Antenna
"Padj", ll-VI-1966, G. Anufriev (1 S). and head black; mandible yellow with apex
Kuriles, Kunashiri, Yambetsu, 22-25-VlI- reddish brown. Thorax black. Fore- and
1935, T. Uchida (1 9, 5 d); Etorofu, Porosu midlegs black with tibiae and tarsi yellow;
14-15-V11-1936 (2 c?), Seseki 16-18-VlI- hindleg black with tibiae yellow except for
1936, Y. Sugihara (1 9) (identified as C. black on about apical fourth. Abdomen
camtschatcalis by Takeuchi). Kunishir Is- black with small lateral spots on segments
land, Alekhino Vil., wet meadow along for- 3 or 4-7, spots small and separated; some-
est stream, 27-VI-1971, V. Ermolenko (2 times a narrow, incomplete yellow trans-
S). Shikotan Island, Krabozavodsk Vil., verse band on posterior margin of segment
meadows along Pacific Ocean, on flower of 6; apex of 9th tergite narrowly yellow. Ob-
Ranunculus sp., 6-V11-1071, V. Ermolenko long plate (valvifer 2) narrowly yellow on
(7 9,4 6). Shikotan Island, Malo-Kuril'sk margin. Wings hyaline; costa and anterior
Vil., meadows along Pacific Ocean, 9-Vll- margin of stigma yellowish, rest of stigma
1971, V. Erm—olenko {\ S). and veins black. Antenna with 18 to 22 seg-
Remarks. Ivie and Zinovjev (1996) ments; preapical segments about as broad
synonymized C. hyalinatus under Cephus as long. Hindtibia with 2 preapical spines.
cinctus Norton 1872 described from North Tarsal claw with small inner tooth, much
America; thus, concluding that the same smaller t—han outer tooth.
species occurs in Asia and North America Male. Length, 6.0-8.0 mm. Head and
and that the North American populations thorax black; inner ventral surface of cer-
may have been the result of an early intro- vical sclerite sometimes with yellow spot,
duction from Asia. This synonymy is still and sometimes small yellow spot on dorsal
open to question, and we prefer to call the corner of mesepisternum; perapteron yel-
Japanese specimens C. hyalinatus pending low. Fore- and midlegs with coxae yellow
additional proof for the synonymy. anteriorly, black posteriorly; trochanters
This species was recorded from Hokkai- yellow anteriorly; outside margin offemora
do by Takeuchi (1936, 1938), the latter ref- black, inside margin of femora and tibiae
erence correcting his 1936 identification of and tarsi yellow; hindleg similar but black
C. camtschatcalis to C. hyalinatus. We have mainly at base of coxa with apical half or
seen the specimen on which Takeuchi based more yellow. Abdomen with lateral yellow
this record and confirm his identification as spots on segments 3 or 4 to 7, sometimes
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VOLUME 104. NUMBER 2 483
small on 3; transverse yellow bands on pos- mens, the preapical antennal segments are
terior margins of—segments 4 and 6. about as broad as long, and the sawsheath
Japan records. Honshu: Mt. Hakkoda, is in a direct line with the oblong plate.
Aomori Pref.. 20-VII-1965, T. Naito leg. (2 Because ofthe favorable similarity ofthe
S); Sukayu. Aomori Pref., 20-VII-1965, Japanese specimens with C. brachycercus,
col. T. Naito (2 9,5 6): Mt. Hakkoda (To- we believe it is best to refer these speci-
wadako), Aomori Pref., 7-VIII-1988, M. mens to that species. Since we are not sure
Yamada (1 d); Mt. Iwaki, Aomori Pref., ofthe significance ofthe characters used by
7-VII-1995, M. Yamada (19); Sasayama, Benson, and since the entire genus needs
Hyogo Pref., 27-V-1954, S. Momoi (19,3 revisionary study, we prefer not to describe
S). a separate species at least until taxonomic
Remarks. Cephus brachycercus occurs problems within the genus are resolved.
in Europe and has been recorded from Si-
beria, at least to the Irkutsk Region (Gus- Acknowledgments
sakovskij 1935, Verzhutskii 1966, Zhelo- We thank H. Hara, Hokkaido Forestry
chovtsev and Zinovjev 1996). We have not Research Institute, Bibai; M. Ohara, Hok-
seen records from farther east, but it could kaido University, Sapporo; T. Hirowatari,
occur in more eastern regions and into Ja- University of Osaka Prefecture, Sakai; T.
pan, or it could be an introduction into Ja- Naito, Kobe University, Kobe; and M. Ya-
pan. The specimens agree with C. brachy- mada, Hirosaki, for the loan or gift of ma-
cercus specimens from Europe and key to
terial.
C. brachycercus in existing keys (e.g., Gus-
sakovskij 1935). It is not a species treated Literature Cited
by Takeuchi (1938).
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and the hindleg is black with only the base sects, Vol. VI, Part 2(a), 49 pp.
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(1996) treated C. camtschatcalis as a ques- ences de rURSS 27: 363-381.
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sometimes may have small yellow spots. mologist 128: 347-348.
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