THE ENITHARES (Hemiptera-Heteroptera: Notonectidae) OF THE ...

390 Pacific Insects Vol. 10, no. 2
6*6*. Length ll mm, maximum width 4 mm; ##, length 11.25 mm, maximum width 3.75 mm.
Color : Pale form, eyes reddish brown flecked with black. Vertex, pronotum and elytra including
membrane yellowish brown and semi-hyaline. Abdomen ventrally dark brown, keel,
lateral margins and legs yellowish brown. Dark form, eyes pale reddish brown. Vertex yellowish
brown. Pronotum, scutellum, elytra and opaque zone of membrane very dark brown.
Lateral margins of pronotum, scutellum laterally, clavus and corium with paler brown linear
areas. Anterior and posterior lobes of membrane, legs, keel and lateral margins of sternites
pale brown. Abdomen ventrally black.
Structural characters : Head in dorsal view rounded. Greatest width of head about 5/6 pronotal
humeral width, nearly 2.25 X anterior width of vertex and 2.5 X median head length. Synthopsis
just over 1/2 anterior width of vertex. Median head length slightly shorter than anterior width
of vertex and equaling median pronotal length in & ; $• slightly longer. Pronotal humeral
width over 3X median length in & ', R- Just less than 3X median length. Lateral margins convex,
about 1/2 median length, posterior margin almost straight. Dorsal margin of pronotal
fovea directed obliquely caudad before turning laterad (fig. 116). Nodal furrow short and
straight, directed dorsad, more than its own length removed from membranal suture (fig. 128).
Both sexes with a row of small but distinct transverse ridges along 1st 3 and part of 4th visible
ventral Connexival segments. These ridges are on extreme outer margin of connexivum. Mesotrochanter
rounded (fig. 111) chaetotaxy of & mid-leg (fig. 111-113). Male genital capsule as
in fig. 114, parameres elongate with hairs at apex, posterior lobe with a distinct 'step' dorsally.
Metaxyphus as in fig. 115.
Holotype &, China, Datchulan, 1939, T. H. Cheng (USNM), Brooks, (1948 : 43) also
referred to a $ and £ paratype from China, Foochow, Chenfu F. Wu in the 'Imperial
Museum in Japan' These specimens are in fact in the SECK. Through the courtesy of
Dr Byers, I have been permitted to examine them. Also, I have seen the following material
: Macao, J. C. K. Coll. 1 $ & 1 $ (BISHOP) The $ from Macao was sent to Dr
Froeschner, Washington for comparison with the type, he reported as follows, lO.xii. 1965
"First, my comparison with the type of chinensis. I can report with confidence that your
specimen and the type are conspecific." China, Foochow, Chenfu F. Wu, Det China 1931
as E. biimpressa (Uhler) 1# & 1$ (BMNH). China, Yen-Ping, 21.VII.1917, Ac. 5148,
1$ (AMNH). Laos, R. V. de Salvaza, 1$ (LEIDEN).
Comparative notes : Very closely allied to biimpressa by the minutely serrated ventral
Connexival segments and the male genitalia. The nodal furrow of chinensis is more than
its own length removed from the membranal suture (fig. 128) whereas in biimpressa it is
equal to or less than its own length removed from the membranal suture (fig. 124). Viewed
laterally, the posterior margin of the pronotal fovea of biimpressa (fig. 123 £) is produced
towards the posterior margin of eye, but not so in chinensis (fig. 127 £).
Enithares biimpressa (Uhler) Fig. 117-126.
Bothronotus biimpressus Uni., 1860, Proc. Acad. Nat. Sci. Philad. 1860: 231.
Enithares biimpressa : Hoffmann, 1933, Lingnan Sci. J. 12 : 256.—Wu, 1935, Cat. Ins. Sin. 2 : 576,
ex parte.— Hoffmann, 1941, Lingnan Sci. J. 20 : 61.
##. Length 10 mm, maximum width 4.5 mm; #£, length 10-10.5 mm, maximum width 4 mm.
Color : Pale form, yellowish brown, hyaline and shining. Dark form with eyes reddish
brown. Vertex and pronotum anteriorly yellowish brown, medianly almost hyaline yellowish,