Aegidinus brasiliensis Arrow, 1904

Colby, Julia, 2009, Monographic revision of the genus Aegidinus Arrow (1904) and generic phylogeny of the world Orphninae (Coleoptera: Scarabaeidae: Orphninae)., Insecta Mundi 2009 (76), pp. 1-41 : 15-17

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Aegidinus brasiliensis Arrow, 1904


Aegidinus brasiliensis Arrow, 1904 Fig. 6 View Figure 1-9 , 38-39 View Figures 38-49 , 65 View Figures 65-77 , 82

Aegidinus brasiliensis Arrow 1904: 739 .

Type Material. Holotype male and one paratype (labeled as female; actually a minor male) from Ega , Brazil examined ( BMNH).

Description. Male. (n = 10) Length 7.6-11.7 mm; width 4.3-5.7 mm. Color: Head, pronotum, and elytra black, piceous, or reddish brown. Legs and venter reddish brown. Head: Frons concave medially, punctate; punctures sparse, small. Frontoclypeal suture obsolete. Clypeus punctate, punctures sparse, small. Anterior margin of clypeus with erect, median horn (major) or tubercle (minor); carina (major) or carinula (minor) extending from base of horn laterally to each eye canthus. Pronotum: Surface punctate; punctures moderately dense to dense, moderate to large, occasionally umbilicate, concentrated on sides. Basal margin with partially effaced bead and complete to incomplete row of punctures (punctures may be obsolete adjacent to scutellum; punctures oblong to round, generally one puncture width apart. Disc with subtriangular fovea (major) or oval depression (minor), basolateral edge raised into carina or low, rounded tumosity on either side (major) or not (minor). Fovea or depression punctate; punctures sparse to dense, moderate in size, occasionally transverse. Anterior margin of pronotum with median, subquadrate tubercle (major) or smaller, raised boss (minor). Elytra: Punctures of striae vermiform, elongate, U-, V-, J-, or reverse J-shaped. Striae 1 and 2 obsolete at base. Lateral margin adjacent to humerus with 9-13 setose crenulations. Legs: Protibia without apical denticle. Genitalia: Fig. 6 View Figure 1-9 , 38-39 View Figures 38-49 .

Female (n = 17). Length 7.5-10.7 mm; width 4.2-5.7 mm. Females differ from males in the following respects: Head: Frons not concave, impunctate to punctate; punctures sparse to moderately dense, small. Anterior margin of clypeus without horn or tubercle. Pronotum: Basal margin with bead and row of punctures; punctures obsolete in middle third. Disc with oval to transversely oval depression or not. Anterior margin without median boss or tubercle. Elytra: Lateral margin adjacent to humerus with 6-12 setose crenulations. Genitalia: Fig. 65 View Figures 65-77 .

Diagnosis. Aegidinus brasiliensis is best distinguished using male ( Fig. 6 View Figure 1-9 , 38-39 View Figures 38-49 ) and female genitalia ( Fig. 65 View Figures 65-77 ). The genitalia of this species are similar in appearance to those of A. howeae , but the two are easily separated. The female genitalia of A. brasiliensis have a ridge on the anterior border of the inferior sclerite which is absent in A. howeae ( Fig. 69 View Figures 65-77 ). In males, the length of the sickle shaped anterior angle of the lateral lobes is diagnostic. The lateral lobes are long enough to touch medially in A. brasiliensis but are much shorter (and not touching) in A. howeae ( Fig. 56-57 View Figures 50- 64 ).

Distribution (Fig. 82). Guyana, Brazil. Twenty-seven specimens from BMNH, HAHC, UNSM, and SEMC: BRAZIL (7): Amazonas: Ega (2); Rio Madeira (Borba) (1); Reserva Ducke (26 km NE Manaus) (3). Rondonia: Porto Velho (BR 319, km 866) (1). GUYANA (19): Potaro-Siparuni: Iwokrama Forest Reserve (12); Iwokrama Forest, Turtle Mt. Base Camp (1); Iwokrama Field Station (1 km W Kurupukari) (6). UNKNOWN (1): Amazon (1).

Temporal Distribution. January (1), May (4), May-June (15).

Natural History. Specimens were collected from elevations between 50- 200 m.














Aegidinus brasiliensis Arrow, 1904

Colby, Julia 2009

Aegidinus brasiliensis

Arrow, G. J. 1904: 739