5169915514

20

surface black with the mesosternum and last abdommal segment red, sometimes a little infuscated; epipleurs yellow; front, middle and hind tarsal claws yellow; median lobe of aedeagus very broad and rounded at the apex.

9 from all other species except G. subsłriatus Steph, G. substriatus has a variety with a fine puncturation (var. siculus Reg.) which is extremely

This species is readily separated from all other European species, known to science, by its broad aedeagus, the sides of which are very sinuous and the apex rounded. The shape and the fine puncturation, together with the particoloured underside and the yellow tarsal claws, separate the

similar to that of G. distinctus. The

f

t

\

■ 4--

of G. distinctus are

with

rather morę elongated, the apex of the elytra is slightly morę sharply and transversely truncated; the punctures of the elytral striae are morę uniformly impressed and the fine puncturation is usually morę pronounced. All these differences are slight and I find it almost impossible to separate all the certainty, although the majority are easily named.

Gyrinus paykulli Ochs 1927

Average size Largest:

s

ma

llest:

Size of

6,50 x 2.80 mm,

6.85    x 3.00 mm, 6,25 x 2,55 mm,

6.85    x 2,05 mm.

near Wigry, Pond

Localities: — Lakę Wigry, V, 1031, 3    ", 1    _: ;

Nr, 3, V, 1931, 1 o'.

Convex; apcx of elytra roundly and obliquely truncated; pronotum and elytra not finely punctured; punctiires of elytral striae uniformly and well impressed; nbove black and aenescent, under surface black with the mesosternum and last abdominal segment red, fuscous, or black, epipleurs yellow, sometimes infuscated; front, middle and hind tarsal claws yellow, median lobe of aedeagus very narrow and tapering to a sharp point.

The species is easily distinguished from olhers with the exception of G. ccispius Alen. Prom this it may be separated by

(G

its larger size, the rounded truncature of the

pius has the apex of the elytra sharply and transvcrscly truncated) and the characteristic median lobe ol the aedeagus which almost cxactly resembles that of G. marinus. The specimens