A new species of the genus Apsilops Förster (Hymenoptera: Ichneumonidae: Cryptinae) from Japan; parasitoid of an aquatic crambid moth
Author
Yoshida, Takuma
Author
Nagasaki, Osamu
Author
Hirayama, Tomoko
text
Zootaxa
2011
2916
41
50
journal article
46665
10.5281/zenodo.206662
df440c7d-9f2f-4b16-a0e0-57f4c652c66d
1175-5326
206662
Genus
Apsilops
Förster
Apsilops
Förster, 1869
See
Yu
et al
. (2005)
for synonymy.
Townes (1970)
placed this genus in the tribe Mesostenini (
Cryptini
of authors) based on the absence of sublateral triangular projections on the posterior rim of metanotum. His treatment is accepted by
Carlson (1979)
,
Chiu
et al
. (1984)
,
Schwarz and Shaw (1998)
,
Yu
et al
. (2005)
and others.
Yoshida
et al
. (2009)
, following Townes’ classification, further stated that the genus has a close relationship with
Amauromorpha
and
Thrybius
based on their association with water as well as their characteristic shape of clypeus. In contrast,
Sawoniewicz (2008)
regarded
Apsilops
as a member of a different tribe,
Aptesini
. Although he did not state the evidence for his treatment, it is likely because
Apsilops
has some unusual character states for
Cryptini
but usual for
Aptesini
, namely, the well-developed propodeal carination and thick antenna. In this study, we continue to follow Townes’ classification, however further studies are needed to revise the taxonomic position of the genus.
Diagnosis.
Body exceptionally densely covered with setae. Antenna fusiform, gradualy thickened toward around 2/3 of its length from base, then gradually attenuate to apex; not flat ventrally. Female first flagellomere obliquely truncate apically, as long as 2nd flagellomere (in
A
.
sericata
) or shorter than 2nd flagellomere (other than
A
.
sericata
) (
Fig. 7
). Clypeus strongly convex, impressed along apex (
Fig. 4
). Clypeal apex truncate or weakly concave, without median tooth (
Fig. 3
). Occipital carina joining hypostomal carina far above mandibular base. Mandibular teeth subequal (
Fig. 6
). Posterior metanotal rim without sublateral triangular projections. Propodeal carinae almost complete: lateromedian longitudinal carina obliterated only on area petiolaris (species other than
A
.
sericata
), or obliterated also on area basalis (
A
.
sericata
); anterior transverse carina complete (species other than
A
.
sericata
), or obsolescent; lateral longitudinal carina and posterior transverse carina complete; sublateral crest of apical transverse carina strong (
Fig. 8
). Areolet large, about 0.7–0.9 as high as length of vein 2m-cu, closed at apex (
Fig. 14
). Mediella weakly and evenly arched. Upper valve of ovipositor with teeth between nodus and apex (
Fig 17
).
Apsilops
closely resembles
Amauromorpha
in having dense velvety pubescence. This character state is considered to be an adaptation to trap air when individuals are under water (
Cushman 1933
;
Bennett 2008
). In addition, these two genera are similar in clypeal shape and in having teeth on the upper valve of the ovipositor, but
Apsilops
is clearly distinguished from
Amauromorpha
by the large, closed areolet on the fore wing, more developed propodeal carinae, and lack of a lobe from the lower valve of the ovipositor enclosing the upper valve tip.
Biology.
Aquatic moths of the families
Crambidae
and
Noctuidae
, which are stem-borers or case-carriers feeding on aquatic plants, have been recorded as hosts.
Hagen (1956)
reviewed biological information concerning North American species, and
Sawoniewicz (2008)
provided a list of hosts of the world species.
There are also some host records for undetermined
Apsilops
species in rice paddies in southeast Asia. Two crambid moths,
Scirpophaga incertulas
(Walker)
(the yellow rice stemborer) and
Parapoynx stagnalis
(Zeller)
(the rice caseworm) were recorded as hosts in
India
by
Rao
et al
. (1968
,
1969
). Both species are pests of rice in the Oriental Realm.
Momoi (1969)
reported one female of
Apsilops
sp. collected in a sweep-net in a paddy field of
Taiwan
.
Sinu
et al
. (2007)
studied the host searching behavior of an undetermined species of
Cryptinae
parasitizing pupae of the rice caseworm, stating that their wasp belongs to a genus near
Litochila
. They reported that the wasp oviposited underwater. On the grounds of the reported host and host searching behavior, this wasp is probably
Apsilops
.