Megaceras laevipenne Prell 1914

Alvarez, Héctor Jaime Gasca, da, Claudio Ruy Vasconcelos, Fonseca & Ratcliffe, Brett C., 2008, Synopsis of the Oryctini (Coleoptera: Scarabaeidae: Dynastinae) from the Brazilian Amazon, Insecta Mundi 2008 (61), pp. 1-62 : 30-32

Megaceras laevipenne Prell 1914

( Fig. 51-57 )

Megaceras laevipenne Prell 1914: 214

DESCRIPTION. Length: 30.4-35.3 mm (males); 29.3-32.0 mm (females). Width: 18.6-19.7 mm (males); 17.9-19.1 mm (females). Color: Black.

Males. Head: Frons with long, recurved horn, posterior margin of horn with small, tooth-like swelling near apex, apex rounded ( Fig. 52 ). Eye canthus with rounded apex, anterior margin weakly contracted, surface rugose. Clypeus broad, apex rounded ( Fig. 53 ), sometimes with the border weakly crenulate, surface punctate. Antenna with 10 segments, club subequal in length to segments 2-7. Mandibles with 2 teeth, external tooth larger, broad, apex rounded; internal tooth with narrow apex. Pronotum: Protuberance high, long, bifurcated; apex with 2 small, subparallel to weakly divergent horns ( Fig. 52 ). Lateral margins with a band of spaced rugae, rugae connected to areola apposita. Scutellum: Smooth or with sparse deep punctures, triangular. Elytra: Surface smooth, without sutural stria, margins with sparse punctures. Pygidium: Surface weakly punctate, basal half with a band of reddish brown setae. Lateral angles finely punctate. Legs: Protibia tridentate. Apex of posterior tibia with a spur. First tarsomere of posterior tarsus triangular, apex extend into long spine. Venter: Prosternal process long, weakly laminar, apex rounded with long setae, base with small prominence. Parameres: Long and slender, convex, lateral margins with small tooth near apex, inner sides setose ( Fig. 55-56 ).

Females. As males except in the following respects: Head: Frons with a small, conical tubercle, surface rugose. Pronotum: Surface with small punctures, with 2 small tubercles behind anterior margin. Pygidium: Surface finely punctate, with a strong transverse furrow ( Fig. 54 ).

DIAGNOSIS. Megaceras laevipenne may be distinguished by the absence of a strongly impressed sutural stria and the slender form of parameres. Males of M. laevipenne could be confused with the males of M. crassum . Females of M. laevipenne can be recognized by the deep, strong transverse furrow on the pygidium.

DISTRIBUTION. Megaceras laevipenne occurs in Colombia and Guyana ( Endrödi 1976). The specimens listed below from Brazilian Amazon states represent NEW COUNTRY RECORDS.

LOCALITY RECORDS. ( Fig. 57 ) 17 specimens examined (7 males, 10 females). Specimens were seen from the following collections : INPA, CZPB, MZSP, MPEG.

AMAPÁ (1): Serra Lombard (Limão). AMAZONAS (16): Coari (Rio Urucu, RUC 39, RUC 27, LUC 09), Manaus (Am 10 km 45); Maues (Javaretê), Parque Nacional do Jaú, São Gabriel da Cachoeira (Querari), Taracuá (Rio Uaupés).

TEMPORAL DISTRIBUTION. February (8), April (2), August (2), October (1), December (1).

BIOLOGY. Adults are nocturnal and are attracted to lights. Megaceras laevipenne has been collected from semi-humid ombrophilous forests and areas of seasonal whitewater inundation forest (várzea) at elevations of 30-115 meters.

Figures

Figure 57. Distribution of Megaceras laevipenne in Brazilian Amazonia.

Figure 51-56. Megaceras laevipenne. 51) Habitus. 52) Male head and pronotum (lateral view). 53) Male head (dorsal view). 54) Female pygidium (scale line: 5 mm). 55) Parameres frontal view. 56) Parameres lateral view (scale line: 2 mm).