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

Aegidinus brasiliensis Arrow, 1904 Fig. 6 , 38-39 , 65 , 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 , 38-39 .

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 .

Diagnosis. Aegidinus brasiliensis is best distinguished using male ( Fig. 6 , 38-39 ) and female genitalia ( Fig. 65 ). 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 ). 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 ).

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.

Figures

Figure 1-9. Scale bar = 1 mm. 1) Mouthparts exposed beyond clypeus. a) Labrum exposed beyond edge of clypeus. b) Single, external, lateral lobe on mandibles. 2) Apical spines of metatibia (indicated by arrows) separated by basal metatarsal segment. 3) Female genital sclerites of Aegidinus brasiliensis Arrow. a) Superior sclerite. b) Inferior sclerite. c) Interior process. 4). Female genital sclerites of A. oreibates Colby. a) Superior sclerite. b) Inferior sclerite. c) Accessory sclerite. 5) Male parameres (frontal view) of A. oreibates. a) Lateral lobe. b) Median lobe. 6) Male parameres (frontal view) of A. brasiliensis. a) Lateral lobe. b) Median lobe. 7) Male parameres and phallobase (lateral view) of A. guianensis (Westwood). a) Lateral lobe. b) Median lobe. c) phallobase. d) Basal piece of phallobase. 8) Attachment of first antennal club segment to stem offset (Hybalus sp.). 9) Attachment of first antennal club segment to stem not offset (Orphnus sp.).

Figures 38-49. Male genitalia. Scale bar = 1 mm. 38) Parameres (frontal view) of Aegidinus brasiliensis. 39) Parameres and part of phallobase (lateral view) of A. brasiliensis. 40) Parameres (frontal view) of A. candezei. 41) Parameres and part of phallobase (left, lateral view) of A. candezei. 42) Ventral plate of A. candezei. 43) Parameres and part of phallobase (right, lateral view) of A. candezei.44) Parameres (frontal view) of A. cornutus. 45) Parameres and part of phallobase (lateral view) of A. cornutus. 46) Parameres (frontal view) of A. crypticus. 47) Parameres and part of phallobase (lateral view) of A. crypticus. 48) Ventral plate of A. crypticus.49) Lateral lobe of A. crypticus.

Figures 65-77. Female genitalia, gonocoxites. Scale bar = 1 mm. 65) A. brasiliensis. 66) A. candezei. 67) A. guianensis. 68) A. howdenorum. 69) A. howeae. 70) A. oreibates. 71) A. simulatus. 72) A. sunidigea. 73-74) A. teamscaraborum. 75) A. tricornus. 76) A. unicus. 77) A. venezuelensis.

Figures 50- 64. Male genitalia. Scale bar = 1 mm. 50) Parameres (frontal view) of A. guianensis. 51) Parameres and part of phallobase (lateral view) of A. guianensis. 52) Parameres (frontal view) of A. howdenorum. 53) Parameres and part of phallobase (lateral view) of A. howdenorum. 54) Ventral plate of A. howdenorum. 55) Lateral lobe of A. howdenorum. Arrow indicates notch. 56) Parameres (frontal view) of A. howeae. 57) Parameres and part of phallobase (lateral view) of A. howeae. 58) Parameres (frontal view) of A. oreibates. 59) Parameres and portion of phallobase (lateral view) of A. oreibates. 60) Ventral plate of A. oreibates. 61) Parameres (frontal view) of A. petrovi. 62) Parameres and part of phallobase (lateral view) of A. petrovi. 63) Parameres (frontal view) of A. teamscaraborum. 64) Parameres and part of phallobase (lateral view) of A. teamscaraborum.