Megaceras philoctetes ( Olivier 1789 )

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 : 33

Megaceras philoctetes ( Olivier 1789)

( Fig. 58-64 )

Scarabaeus philoctetes Olivier 1789: 16

Megaceras teucer Burmeister 1847: 223 (synonym)

Megaceras lycaon Endrödi 1976: 32 (synonym)

DESCRIPTION. Length: 39.2-51.5 mm (males); 32.3-49.6 mm (females). Width: 19.6-26.9 mm (males); 12.1-28.2 mm (females). Color: Black.

Males. Head: Frons with long, recurved horn, posterior margin of horn with small, tooth-like swelling near apex, apex weakly acuminate. Eye canthus with rounded apex, anterior margin elevated forming a furrow, surface rugose. Clypeus with 2 strong teeth at apex ( Fig. 59 ), surface finely punctate. Antenna with 10 segments, club subequal in length to segments 2-7. Mandibles with 2 subequal, triangular teeth, apex narrow. Pronotum: Majors ( Fig. 60 ) with high, broad, bifurcated protuberance, apex with 2 small, subparallel, weakly curved downward horns. Surface slightly punctate, lateral margins with a band of spaced rugae, rugae connected to areola apposita. Minors ( Fig. 61 ) with smaller protuberance, horns of the apex small, band of rugae reaching the apex. Scutellum: Smooth , triangular. Elytra: Smooth, sutural stria weakly impressed. Pygidium: Surface punctate, base with a band of reddish brown setae. Lateral angles finely rugose, surface convex in lateral view. 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, slightly convex, apex rounded to quadrangular with dense setae. Parameres: Pyriform, sides with a long, strongly projected tooth, apex dilated and setose ( Fig. 62-63 ).

Females. As males except in the following respects: Head: Frons with conical tubercle, surface rugose. Pronotum: Surface smooth, without tubercles or tubercles very small behind anterior margin; sides with sparse punctures.

DIAGNOSIS. Megaceras philoctetes is characterized by its bidentate clypeus, frontal horn with apex acuminate, and pyriform parameres. Minor males could be confused with major males of M. laevipenne when the teeth of the clypeus are not well developed.

DISTRIBUTION. Megaceras philoctetes is known from Venezuela, Brazil, French Guiana,, Bolivia, Colombia and Peru. Dechambre (1998c) suggested the last two records should be confirmed because they lack specific data.

LOCALITY RECORDS. ( Fig. 64 ) 42 specimens examined (19 males, 23 females). Specimens were seen from the following collections : INPA, CZPB, MZSP, IBSP, MPEG, UNSM.

AMAPÁ (2): Calçoene, Reginá, Serra do Navio . AMAZONAS (16): Benjamin Constant, Iranduba (Cacau Pireira), Manaus ( BR 174 km 153), Presidente Figueredo, Rio Preto da Eva ( Am 10 km 174), Taracua ( Rio Uaupés ), Tefé ( São Mateus ); Parque Nacional do Jaú ( Rio Carabinani ) . PARÁ (21): Belém, Cachimbo, Cassidoré, Óbidos (Traira), Ourém Patauateva ( Fazenda Gavião Real ) . RONDÔNIA (1): Vilhena .

TEMPORAL DISTRIBUTION. January (4), February (3), April (10), May (4), June (3), July (1), August (1), September (5), October (2), November (3), December (2).

NOMENCLATURAL REMARKS. Reiche (1859) established Megaceras teucer as a synonym of Megaceras philoctetes . This was confirmed by Dechambre (1975) and Endrödi (1985). In subsequent works Dechambre (1998c) compared the morphology of the parameres and determined Megaceras lycaon Endrödi, 1976 , as new synonym of M. philoctetes .

BIOLOGY. Adults are nocturnal and are attracted to lights. In Brazilian Amazonia, M. philoctetes has been collected from ombrophilous forests, secondary forests, and floodplain areas at elevations ranging from the sea level to 600 meters.

Figures

Figure 64. Distribution of Megaceras philoctetes in Brazilian Amazonia.

Figure 58-63. Megaceras philoctetes. 58) Habitus. 59) Male head (dorsal view). 60) Male major. 61) Male minor (scale line: 5 mm). 62) Parameres frontal view. 63) Parameres lateral view (scale line: 2 mm).