Memoirs on the coleoptera

200 MEMOIRS ON THE COLEOPTERA
with earthy matter; head moderately impressed and punctured, the
pale hairs stout; prothorax fully two-thirds wider than long, nearly as
wide as the elytra (cf ) to decidedly narrower ( 9 ), rather wider at the
middle than at the basal angles, the latter acute and posteriorly
prominent but scarcely at all everted, the sides rather strongly, evenly
arcuate, more converging anteriorly to the acute and seldom very
evidently blunted apical angles, the apex three-fifths as wide as the
base, less deeply sinuate than in immunda; surface similar but becoming
coarsely punctato-rugose medially in the female, though not
in the male; elytra short, barely two-fifths longer than wide, the
parallel sides more strongly arcuate than in the preceding species,
rounding inward posteriorly behind the middle, the apical lobe
moderately differentiated; surface rather less flat, each with about
four close-set irregularly sinuous unduliform and feebly tumid lines,
the side margins reflexed throughout, strongly toward base but not
much thickened; abdomen more shining than in immunda, punctate
apically; legs rather more slender. Length (cf , 9
) 15.0-16.0 mm.;
width 7.7-8.5 mm. New Mexico (Magdalena Mts.), Snow.
ccenosa n. sp.
It is highly probable
that nitidula and tensa are related to man-
cipata, in spite of the very different type of elytral sculpture in-
ferable from the original description of the latter species, and, as
nitidula is certainly a member of the opaca group, very evidently
connected with the more normal species through tensa, it follows,
if this surmise is correct, that mancipata
is also a member of the
opaca group and that a special group for that species is unnecessary.
The finely and sparsely punctate head and three irregular elytral
ridges, united transversely by anastomosing reticulation, stated of
mancipata, coupled with the broader elytral base, would indicate
that it cannot be a modification of nitidula, but as in tensa the head
is finely and sparsely punctate and the elytra may be conceived to
have each three broad and feebly elevated lines, it is supposable
that mancipata may be related more closely to tensa than to ni-
tidula; but tensa has the elytra no wider at base than the prothorax
and the elytral ridges are separated by feeble irregular and equally
wide depressed lines, or rather depressions caused by the more
lineiform arrangement of the very irregular indentations and in
no way united by reticulation. Grant Co., New Mexico, the local-
ity of mancipata, lies in the extreme southwestern angle of the territory,
about 200 miles south of Fort Wingate, McKinley Co.
The Kansas specimens of opaca are obviously flatter in the elytra
than the Colorado specimens and may be subspecifically different.