Memoirs on the coleoptera

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MEMOIRS ON THE COLEOPTERA
daire, should be excluded and is made the type of the genus Taranomis
as stated above.
Plionoma n. gen.
Besides suturalis Lee. (Sphenothecus) and 5. rubens Csy., the
latter being a distinct species and not a variety of suturalis, we
have another definable as follows:
Plionoma degener n. sp. Smaller and narrower than rubens, shining,
piceous-black, the prothorax bright red; under surface deep black, the
prosternum transversely rufescent; femora red, the tibiae and tarsi
throughout black or nearly so; pubescence pale, short and sparse above,
dense beneath except medially, sparse on the prosternum; head small;
antennae (9) black, about as long as the body, the third joint fully a
fourth longer than fourth to seventh, which are subequal, seven to ten
gradually decreasing, the last much shorter than the tenth; prothorax
nearly as in rubens in form and sculpture but, like the head, much less
pubescent; scutellum much narrower, twice as long as wide; elytra nearly
similar, coarsely, sparsely punctate, the punctures similarly smaller and
closer in a broad sublateral line but scarcely intermixed with smaller
punctures, the pale sutural line similar; under surface nearly similar but
much less pubescent. Length (9) 10.5 mm.; width 3.0 mm. Arizona
(southeastern), Dunn.
Allied to rubens but differing in its smaller size, sparser pubescence,
especially on the head and prothorax above and beneath, in its
dark coloration, narrow scutellum and especially in having the hind
tibiae almost unmodified; in rubens they are slightly incurvate and
The hind
much more notably thickened apically than in degener.
femora are more evidently bispinulose at tip
other species.
Taranomis n. gen.
than in either of the
The type, named above, is the only species of this genus known
to me. The conoidal bivittate prothorax is nearly as in Sphcenothecus,
but the elytra are wholly different in structure. It seems
to be a local development and confined to Texas and adjoining
regions. Besides bivittata Dup., this genus may possibly include
the Ischnocnemis pallida of Schaeffer, from Lower California, but
the probabilities are that it is not strictly congeneric.
Perarthrus Lee., is represented also by a single species, likewise a
local development and confined to the seacoast regions of southern
California. My single representative is much smaller than the
single original male type, being only 8.2 mm. in length; it is a fe-