Key to Neotropical Species of Trichacis
1 Vertex and occiput smooth.............................................................................. 2
- Vertex and/or occiput at least partially coriaceous or coriaceous with striae........................................ 4
2 (1) Hyperoccipital carina absent (Fig. 21 A), Costa Rica .................................... Trichacis acarinata n. sp. Ƥ
- Hyperoccipital carina present............................................................................ 3
3 (2) OOL longer than LOL, T1 shorter than wide, Costa Rica ............................... Trichacis proximata n. sp. Ƥ
- OOL slightly shorter than LOL, T1 as wide as long, Brazil .......................... Trichacis meridionalis (Brues) Ƥ
4 (1) Hyperoccipital carina absent (Figs 17 C, 17D); Brazil ................................... Trichacis punctata n. sp. Ƥ
- Hyperoccipital carina present (Figs 21 B – 21E)............................................................... 5
5 (4) Hyperoccipital carina incomplete or discontinuous, but not reaching eye margin (Figs 21 C – 21E)...................... 6
- Hyperoccipital carina complete, reaching eye margin (Fig. 21 B).............................................. 22
6 (5) In dorsal view, hyperoccipital carina fading before or until reaching level of imaginary line connecting eye inner margin to posterior cephalic margin (Fig. 21 C)...................................................................... 7
- In dorsal view, hyperoccipital carina surpassing level of imaginary line connecting eye inner margin to posterior cephalic margin (Figs 21 D, 21E)................................................................................ 11
7 (6) Temple projection present (Figs 2 B, 3A, 3B)............................................................... 8
- Temple projection absent............................................................................... 9
8 (7) Area of lateral vertex between posterior ocellus and hyperoccipital carina coriaceous (Fig. 2 B); and between hyperoccipital carina and occipital carina coriaceous with longitudinal striae (Fig. 1 H); Bolivia .......... Trichacis acuminata n. sp. Ƥ3
- Lateral vertex coriaceous, without striae; Colombia ........................................ Trichacis acuta n. sp. Ƥ
9 (7) Inter-notaular area entirely coriaceous (Fig. 17 G); Mexico ............................. Trichacis sculpturata n. sp. Ƥ
- Inter-notaular area with only anterior 1/3 coriaceous, other 2/3 smooth.......................................... 10
10 (9) Combined length of T3–T6 less than length of T2 (Figs 12 A, 12E); specialized area of mesoscutellum with cone-like elevation (Fig. 12 B); metasoma not depressed dorsoventrally; Mexico ........................... Trichacis magnifica n. sp. Ƥ3
- Combined length of T3–T6 greater than length of T2 (Fig. 7 F); specialized area of mesoscutellum heart-shaped, moderately elevated; metasoma depressed dorsoventrally (Fig. 8 A); Costa Rica ......................... Trichacis depressa n. sp. Ƥ
11 (6) Mesopleural carina complete (Fig. 9 A); vertex laterally coriaceous, and with well-marked longitudinal striae between hyperoccipital carina and occipital carina (Fig. 8 D); Colombia, Ecuador, Venezuela ............ Trichacis dianae n. sp. Ƥ3
- Mesopleural carina incomplete (Fig. 18 E)................................................................. 12
12 (11) Hyperoccipital carina curving up and merging with stria running along the eye inner margin (Fig. 21 E)................ 13
- Hyperoccipital carina not curving up and not merging with other stria (Fig. 21 D).................................. 15
13 (12) Anteromedial area of T2 (i.e. area situated between anterior pits) slightly concave and with longitudinal striae (Fig. 9 F); Ecuador ...................................................................... Trichacis fernandezi n. sp. Ƥ
- T2 anteromedially (between pits) flattened and smooth....................................................... 14
14 (13) Lateral region of vertex between posterior ocellus and hyperoccipital carina weakly coriaceous, and with cluster of 4-6 well- marked longitudinal curved striae, which seem to emerge from hyperoccipital carina; lateral vertex area between hyperoccipital carina and occipital carina coriaceous (Fig. 15 A); Ecuador ...................... Trichacis pecki n. sp. Ƥ
- Lateral region of vertex between posterior ocellus and hyperoccipital carina markedly coriaceous, with 9-12 well-separated and irregularly curved longitudinal striae, and 2-3 curved transverse striae running between outer margin of posterior ocellus and inner margin of eye; lateral vertex area between hyperoccipital carina and occipital carina coriaceous, and with well- marked longitudinal striae (Fig. 7 C); Costa Rica ....................................... Trichacis delsinnei n. sp. Ƥ
15 (12) Posteromedial region of inter-notaular area broadly concave (Figs 5 E, 5G); Costa Rica ....... Trichacis concavata n. sp. Ƥ
- Posteromedial region of inter-notaular area convex or blunt................................................... 16
16 (14) Inter-notaular area entirely coriaceous (Figs 6 A, 6D); El Salvador; Mexico ................. Trichacis corrugata n. sp. Ƥ
- Inter-notaular area anterior 1/3 coriaceous, otherwise smooth................................................. 17
17 (16) T1 shorter than wide (Figs 13 F, 14B).................................................................... 18
- T1 at least as long as wide.............................................................................. 19
18 (17) Faint, transverse, slightly curved striae present throughout the anterior region of vertex; distance between posterior ocellus and hyperoccipital carina longer than posterior ocellus diameter (Fig. 14 D); Panama ........... Trichacis panamana n. sp. Ƥ3
- Presence of faint, transverse, slightly curved striae restricted to interocellar area; distance between posterior ocellus and hyperoccipital carina shorter than posterior ocellus diameter (Fig. 13 C); Mexico ........... Trichacis mexicana n. sp. Ƥ3
19 (17) Length and width of T1 equal (Fig. 5 A); all lateral vertex region coriaceous...................................... 20
- T1 longer than wide (Fig.18 C); lateral region of vertex betweeen posterior ocellus and hyperoccipital carina coriaceous, and between hyperoccipital carina and occipital carina with well-marked longitudinal striae (Fig. 18 E); Costa Rica ........................................................................................ Trichacis transversata n. sp. Ƥ
20 (19) Notaulus present (Fig. 9 H)............................................................................. 21
- Notaulus absent (Fig. 5 A); Colombia ............................................ Trichacis colombiana n. sp. Ƥ
21 (20) Vertex laterovertically striate-coriaceous; Honduras ........................................ T. laticornis Buhl 2001
- Vertex laterally coriaceous, without striae; Brazil, Costa Rica, Nicaragua, Panama ........... Trichacis hansoni n. sp. Ƥ 3
22 (5) Mesopleural carina complete (Fig. 15 F); Mexico ........................................ Trichacis procera n. sp. Ƥ
- Mesopleural carina incomplete (Fig. 20 E)................................................................ 23
23 (22) Notaulus absent (Fig. 11 A); Mexico .............................................. Trichacis kaulbarsi n. sp. Ƥ3
- Notaulus present..................................................................................... 24
24 (23) Clypeus fused with interantennal process, forming rounded yellow-brown projected sheet (Fig. 4 B); Costa Rica ........................................................................................ Trichacis clypeata n. sp. Ƥ3
- Clypeus and interantennal process well-separated, not forming projecting lamella................................. 25
25 (24) Combined length of T3–T6 less than length of T2......................................................... 26
- Combined length of T3–T6 greater than length of T2; Brazil ......................... Trichacis ariaspennae Buhl 2011
26 (25) Distance between posterior ocellus and hyperoccipital carina less than diameter of posterior ocellus (Fig. 20 C); specialized area of mesoscutellum triangular and moderately elevated (Figs 18 H; 20E); Mexico ....... Trichacis triangulata n. sp. Ƥ3
- Distance between posterior ocellus and hyperoccipital carina greater than diameter of posterior ocellus; specialized area of mesoscutellum circular and elevated (Fig. 6 F); Costa Rica ............................. Trichacis costaricana n. sp. Ƥ