Three new genera of acidocerine water scavenger beetles from tropical South America (Coleoptera, Hydrophilidae, Acidocerinae)
Author
Giron, Jennifer C.
https://orcid.org/0000-0002-0851-6883
Department of Ecology & Evolutionary Biology, and Division of Entomology, Biodiversity Institute, University of Kansas, Lawrence, KS 66045, USA
entiminae@gmail.com
Author
Short, Andrew Edward Z.
Department of Ecology & Evolutionary Biology, and Division of Entomology, Biodiversity Institute, University of Kansas, Lawrence, KS 66045, USA
text
ZooKeys
2018
2018-06-19
768
113
158
http://dx.doi.org/10.3897/zookeys.768.24423
journal article
http://dx.doi.org/10.3897/zookeys.768.24423
1313-2970-768-113
399BCC3E9D6F4231870E05C79B9FD4B0
CB01CA30FFB4F96DFFA2FF86FFAEFFB6
1298776
Crucisternum sinuatus
sp. n.
Figs 3A-D
; 6G, H
; 7
Type material examined.
Holotype (male): BRAZIL: Minas Gerais
: Lassance, -17.83384, -44.50515, 568 m, Cachoeira da Palmeira, flotation of root mats and moss from side of waterfall and seepage, 2.iii.2018, leg. Benetti & team; BR18-0302-04A (INPA).
Paratypes (10): BRAZIL:
Para
: Rio Xingu Camp
52°22'W
,
3°39'S
, Altamira, ca 60km S., 3.x.1986, leg. P. Spangler & O. Flint, Colln. #6, 1st jungle stream on trail 1 (1, USNM); same, except 14.x.1986, Colln. #23, stream on left branch of trail 1 (3; SEMC, USNM);
Minas Gerais
: same data as holotype (2 INPA, 4 SEMC).
Differential diagnosis.
Crucisternum sinuatus
is very similar to
C. escalera
and
C. xingu
in the shallowness of the punctation. In addition, it can be distinguished from
C. xingu
by the aedeagus with median lobe constricted at midlength, continuing as a narrow and roundly pointed bar (see Fig.
6G, H
; as opposed to gradually narrowing towards the apex, see Fig.
6E, F
), and the outer margins of the parameres, which are strongly constricted at apical third, continuing nearly parallel (as opposed to nearly straight to sinuate).
Description.
Body length 2.0-2.4 mm, width 1.1-1.4 mm. General coloration variable, either orange brown or uniformly dark brown (Fig.
3A-D
). Elytra with punctures shallowly marked. Aedeagus with outer margins of parameres strongly constricted at apical third, continuing nearly parallel towards apex; inner margins of parameres slightly concave only along apical sixth; median lobe constricted at midlength, continuing as a narrow and roundly pointed bar (Fig.
6G, H
).
Etymology.
Named in reference to the abrupt constriction of the outer margins of the parameres at their apical third, with the Latin word
sinuatus
meaning bent, curved.
Distribution.
Brazil (Minas Gerais,
Para
). See Fig.
7
.
Biology.
The series from Lassance was collected by floating root mats and detritus that were on rock at the margin of a river and waterfall. The specimens from Altamira were collected in streams.