Ancyloscelis, Latreille, 1829

Schaller, A. & Roig-Alsina, A., 2021, A revision of the bee genus Ancyloscelis (Hymenoptera: Apidae) in Argentina, Zootaxa 4980 (3), pp. 521-540 : 535-536

Key to females

1. Mouthparts with modified, hooked setae ( Fig. 9A–B ) ( ursinus species group)..................................... 2

- Mouthparts with simple or plumose setae, not hooked ( apiformis species group)................................... 6

2. Labial palpus with modified setae only on first segment. Proboscis very long, second segment of labial palpus 1.9 times as long as intertegular span. Clypeus strongly protuberant, clypeocular distance 0.96–1.07 times MOD ( Fig. 1B ). Labrum entirely black................................................................................... A. halictoides

- Labial palpus with modified setae on first and second segments. Proboscis moderately long, second segment of labial palpus 0.6–0.9 times as long as intertegular span. Clypeus less protuberant, clypeocular distance 0.42-0.50 times MOD ( Fig. 1A, C ). Labrum with small mid apical yellow mark, sometimes minute................................................. 3

3. Mid and hind tibial spurs yellowish ( Fig. 1A ). Hairs with wavy apices present next to hypostomal carina, on anterior trochanter, and on S1–S4 ( Fig. 9C )..................................................................... A. bonariensis

- Mid and hind tibial spurs black ( Fig. 1C ). Hairs with apices straight on hypostomal carina, on anterior trochanter, and on S3–S4.............................................................................................. 4

4. Scopa dorsally yellow and white below ( Fig.1D ). Carina of pronotal lobe forming tuberculiform, strong elevation, posteriorly concave ( Fig. 12B )..................................................................... A. mesopotamica

- Scopa dorsally dark and white below ( Fig. 1C ). Carina of pronotal lobe more or less elevated but not forming tuberculiform elevation, not forming a concavity posteriorly (as in Fig. 12A )................................................. 5

5. Disc of T2–T4 with yellowish hairs; apical bands yellowish. Wings membrane brownish, pterostigma and prestigma brownish........................................................................................ A. ursinus

- Disc of T2–T4 with black hairs; apical bands wite to yellowish ( Fig. 1C ). Wings membrane infuscate, pterostigma and prestigma black ( Fig. 1C ).......................................................................... A. holmbergi

6. Mandible with basal yellow spot. Flagellum orange ( Fig. 6A–B ). Smaller species, length of forewing 4.3–5.8 mm ........ 7

- Mandible basally dark. Flagellum black to dark brown ( Fig. 6C–D ). Larger species, length of forewing 5.8–7.0 mm...... 8

7. Scape and pedicel orange ( Fig. 6A ). Labrum usually with lateral yellow spot, although some specimens with dark labrum. IOD 1.5–2.0x OOD............................................................................. A. apiformis

- Scape and pedicel black ( Fig. 6B ). Labrum dark, without yellow lateral spot. IOD 1.3–1.5x OOD.......... A. nigricornis

8. Forewing with dark spot apical to marginal cell, remainder of wing margin lighter ( Fig. 6C )................. A. romeroi

- Forewing with entire apical margin darkened ( Fig. 6D ).............................................. A. saltensis

Figures

FIGURE 1. Females, A. ursinus species group, lateral view. A, A. bonariensis Brèthes. B, A. halictoides (Holmberg). C, A. holmbergi sp. n. D, A. mesopotamica (Holmberg). Scale lines = 0.1 mm.

FIGURE 6. Females, A. apiformis species group, lateral view. A, A. apiformis (Fabricius). B, A. nigricornis Rodríguez & Roig- Alsina. C, A. romeroi (Holmberg). D, A. saltensis Rodríguez & Roig-Alsina. Scale lines = 0.1 mm.

FIGURE 9. A–B, mouthparts of A. bonariensis. A, hooked setae on labial palpus. B, hooked setae on prementum and stipes. C, metasomal sterna S1–S4 of A. bonariensis showing modified setae. Scale lines = 0.5 mm.

FIGURE 12. A–B, dorsal view of female pronotal lobe (p, pronotal lobe). A, A. bonariensis Brèthes. B, A. mesopotamica (Holmberg). C–D, lateral view of male head showing hypostomal carina (h). C, A. halictoides (Holmberg). D, A. bonariensis Brèthes. Scale lines = A–D, 0.2 mm.