Synopsis of the cyclocephaline scarab beetles (Coleoptera, Scarabaeidae, Dynastinae)
Author
Moore, Matthew R.
Author
Cave, Ronald D.
Author
Branham, Marc A.
text
ZooKeys
2018
745
1
99
http://dx.doi.org/10.3897/zookeys.745.23683
journal article
http://dx.doi.org/10.3897/zookeys.745.23683
1313-2970-745-1
16F1AE595650485F9D8C6149E962D461
Ruteloryctes
Arrow, 1908
Types species.
Ruteloryctes tristis
Arrow, 1908: 336, by monotypy.
Valid taxa.
Two species.
The two species of
Ruteloryctes
are distributed in the Guinea-Congo lowland rainforests of West and Central Africa.
Ruteloryctes
specimens have been collected in Angola, Benin, Cameroon, Chad,
Cote
d'Ivoire
, Democratic Republic of the Congo, Guinea, Guinea-Bissau, Nigeria, Senegal, Sierra Leone, and The Gambia (
Burgeon 1947
,
Paulian 1954
,
Endrodi
1960
,
1966
,
1985a
,
Krell et al. 2003
,
Hirthe and Porembski 2003
,
Ervik and Knudsen 2003
) (Fig. 62).
Ruteloryctes morio
is a pollinator of nocturnally blooming
Nymphaea lotus
L., and this floral association has been reported from
Cote
d'Ivoire
, Senegal, and Nigeria (
Fabricius 1798
,
Krell et al. 2003
,
Hirthe and Porembski 2003
,
Ervik and Knudsen 2003
). The immature stages of
Ruteloryctes
are undescribed.
Figure 62. Country-level distribution of
Ruteloryctes
species in Africa. Numbers indicate taxa per country.
Ruteloryctes
species can be recognized by the following combination of characters: 1) dorsal coloration black to dark brown; 2) body convex, not strongly anteroposteriorly compressed or dorsoventrally flattened; 3) clypeal apex truncate or rounded in dorsal view; 4) frontoclypeal suture incomplete medially; 5) males with anterolateral margin of the mandibles lacking weak tooth; 6) mandibular molar area with rows of circular micropunctures; 7) apex of mentum weakly emarginated at middle; 8) galea of maxilla on inner surface with 3 fused basal teeth, a free median tooth, and 2 fused apical teeth (3-1-2 arrangement); 9) pronotum with broadly incomplete beaded basal margin; 10) males and females with 3 protibial teeth on lateral margin, basal tooth not greatly reduced, slightly removed from apical 2 teeth, and oriented laterally; 11) protibial spur straight to weakly deflexed; 12) males with inner protarsal claw enlarged and narrowly cleft at apex; 13) mesocoxae not widely separated, nearly touching; 14) meso- and metatibiae with distal, transverse carinae; 15) metacoxae with lateral edge perpendicular to ventral surface; 16) anterior edge of hindwing distal to apical hinge lacking setae and with produced, membranous border; 17) vein RA with single row of pegs proximal to apical hinge.
The original description of
Ruteloryctes
compared the genus to New World
Dyscinetus
species, and it was hypothesized to have "strayed across the Atlantic" (
Arrow 1908
).
Endrodi
(1966)
thought that
Ruteloryctes
was one of the most
"primitive"
cyclocephaline genera. The 3-1-2 arrangement of the teeth on the maxillary galea in
Ruteloryctes
is most similar to
Arriguttia
,
Augoderia
, and many
Cyclocephala
species. The membranous border of the hindwing present in
Ruteloryctes
is also shared with
Arriguttia
,
Acrobolbia
,
Ancognatha
,
Aspidolea
, and
Cyclocephala
. However, the single row of pegs present on the hindwing RA vein in
Ruteloryctes
is present in
Ancognatha
,
Surutu
,
Harposceles
,
Stenocrates
,
Dyscinetus
,
Erioscelis
, and
Chalepides
.