Ischnomelissa, Engel, 1997

Engel, Michael S., 2013, The bee genus Ischnomelissa in Peru, with a key to the species (Hymenoptera: Halictidae), Journal of Melittology 2013 (23), pp. 1-5 : 4-5

Key to the Species of Ischnomelissa

Females remain unknown for I. ecuadoriana , while males are unknown for I. rhina , I. cyanea , I. rasmusseni , and I. lignopteryx .

1. Females ......................................................................................................................... 2

―. Males ............................................................................................................................. 7

2(1). Malar space as long as or longer than basal width of mandible .......................... 3

―. Malar space shorter than basal width of mandible ............................................. 6

3(2). Head and mesosoma dark to metallic green with copper highlights .................. 4

―. Head and mesosoma dark metallic blue ( Ecuador: Pichincha Province) .............. ............................................................................................. I. lescheni Brooks & Engel

4(3). Metasoma and legs dark brown except sometimes with some amber coloration basally on first metasomal tergum ............................................................... 5

―. Metasoma with first tergum and most of second tergum amber, remainder of metasoma brown, legs with tarsi, tibiae, and femoral apices amber, remainder of legs brown ( Ecuador: Napo and Sucumbios Provinces) ... I. rhina Brooks & Engel

5(4). Metasomal terga entirely dark brown, with well-developed and distinct basal bands of yellow tomentum; wing membrane hyaline and clear; head and mesosoma distinctly dark metallic green and shining; inner metatibial spur with 17 branches, not including apical portion of rachis ( Ecuador: Loja Province) ............................................................................. I. rasmusseni Engel & Brooks

―. Metasomal terga dark brown except basally amber on first tergum ( Fig. 1 ), tergal graduli without bands of tomentum; wing membrane strongly infumate ( Fig. 1 ); head and mesosoma dark green, not shining ( Figs. 1–3 ); inner metatibial spur with 12 branches, not including apical portion of rachis ( Peru: Amazonas Department) ........................................................... I. lignopteryx Engel , n. sp.

6(2). Integument of head and mesosoma dark metallic blue; T1–2 dark brown; inner metatibial spur with 12 branches, not including apical portion of rachis ( Colombia: Nariño Department) ..................................... I. cyanea Brooks & Engel

―. Integument of head and mesosoma non-metallic, dark brown; T1 and most of T2 amber; inner metatibial spur with 15–20 branches, not including apical portion of rachis ( Colombia: Huila and Valle del Cauca Departments ) ... I. zonata Engel

7(1). Malar space almost as long as wide to slightly longer than wide ........................ 8

―. Malar space linear, much shorter than wide ( Colombia: Huila and Valle del Cauca Departments) ........................................................................... I. zonata Engel

8(7). First flagellomere one-half length of second flagellomere; mandible, malar space, and scape at least anteriorly pale; malar space slightly shorter than wide ( Ecuador: Pichincha Province) ................................... I. lescheni Brooks & Engel

―. First flagellomere one-fourth length of second flagellomere; mandible, malar space, and scape dark brown to black; malar space slightly longer than wide ( Ecuador: Imbabura Province) .............................. I. ecuadoriana Brooks & Engel

Figures

Figures 1–4. Photomicrographs of holotype female of Ischnomelissa lignopteryx, new species, from Abra Patricia Reserve, Peru. 1. Lateral habitus. 2. Facial view. 3. Lateral view of head. 4. Detail of inner metatibial spur.