Lomachaeta (Females), 1936

Williams, Kevin A., Cambra, Roberto A., Bartholomay, Pedro R., Luz, David R., Quintero, Diomedes & Pitts, James P., 2019, Review of the genus Lomachaeta Mickel, 1936 (Hymenoptera: Mutillidae) with new species and sex associations, Zootaxa 4564 (1), pp. 101-136 : 103-104

Key to species of Lomachaeta (Females)

1. Mesosoma and T2 disc with matching thickened posteriorly-directed subparallel appressed silvery to golden setae ( Figs 1–3 ; North America)...................................................................................... 2

- Mesosoma and T2 not having matching appressed posteriorly-directed silvery golden setae; dorsum usually without any appressed thickened setae, but if thick setae present on mesonotum, then they are not predominantly subparallel and the T2 disc has erect sparse setae only (e.g. Figs 9, 12 , 21 , 33 ; North or South America).................................. 3

2(1). Mesosoma elongate, thoracic dorsum nearly as long as wide; head wider (~1.2×) than mesosoma ( Figs 2, 3 , 6, 7 ; Texas)........................................................................ L. vacamuerta Williams & Pitts, 2009

- Mesosoma more compact, thoracic dorsum shorter (0.85×) than wide; head as wide as mesosoma ( Figs 1 , 5 ; Arizona, Nevada, Utah).............................................................. L. argenta Pitts & Manley, 2004

3(1). Areolations on frons and vertex broad, most transverse intervals obliterated, leaving variously defined apparent longitudinal carinae; lateral pronotal and propodeal faces with areolations having intervals more clearly defined, at least one complete areolation on mesopleuron and lateral propodeal face; body variegated dark and light brown or primarily dark-brown ( Figs 9, 10 , 15, 16 ; Central and South America only)................................... L. hyphantria Pitts & Manley, 2004

- Areolations on frons and vertex variable, either complete or with obliterated edges not oriented to leave longitudinal carinae; lateral pronotal and propodeal faces often with areolations largely obliterated; body often predominantly orange-brown (North, Central, or South America)...................................................................... 4

4(3). South American species; mesosomal areolations dense, intervals narrow and even, not scabrous ( Figs 12–14 )........... 5

- North and Central American species; mesosomal sculpture variable, areolations often sparser with intervals partially obliterated, sometimes appearing scabrous (e.g. Figs 22, 23 , 33, 34 )................................................. 7

5(4). Mesosoma, metasoma, and legs black, head orange-brown; entire body except T2 disc with appressed setae thickened, white, contrasting with integument ( Figs 12 , 18 ; São Paulo, Brazil)............................. L. meloi Williams , sp. nov.

- Head and mesosoma reddish brown, often darkened laterally, metasoma blackish, always darker than head; body setae predominantly brown.................................................................................... 6

6(5). Propodeal spiracle prominently dentiform; scape as long as pedicel and F1–3 combined ( Figs 11 , 17 ; Buenos Aires, Argentina).............................................................................. L. ibarrai Casal, 1969

- Propodeal spiracle lowly rounded, not dentiform; scape shorter than pedicel and F1–3 combined ( Figs 13, 14 , 19, 20 ; Argentina, Brazil, and Paraguay)............................................................. L. vianai Casal, 1969

7(4). Mandible with baso-ventral subhyaline lamella, mandible narrowed beyond lamella ( Fig. 65 ); pronotal and propodeal spiracles swollen and apparently tuberculate ( Figs 22, 23 ); T1 shape sub-disciform, often with dorsal and anterior faces set apart by angle or incomplete carina; T2 fringe usually composed of thick silvery setae ( Figs 21, 23–26 ); mesosomal dorsum often with dense areolations, at least anteriorly ( Figs 21, 24 ); frequently encountered in trap nests......................... 8

- Mandible without basal lamella, if weak lamella apparently present, it does not interrupt ventral mandible contour ( Fig. 66 ); pronotal and propodeal spiracles usually not so swollen (e.g. Figs 33–36 ); T1 shape sub-sessile, dorsal and anterior faces evenly rounded together; T2 fringe usually composed of sparse slender setae (e.g. Figs 33–35 ); mesosomal dorsum never with areolations dense; not known from trap nests......................................................... 10

8(7). Head and mesosoma reddish brown, metasomal segments 2–6 uniform blackish; mesosomal dorsum with tight subuniform areolations; T6 with dense thickened long setae that are black basally and whitish apically ( Figs 21 , 27 ; subtropical Mexico to Costa Rica)........................................................... L. chionothrix Pitts & Manley, 2004

- Variably colored, usually variegapted light and dark brown, but if metasoma predominantly blackish, then head and mesosoma also dark; mesosomal dorsum usually with fewer areolations that are often broader posteriorly; T6 lacking long thick bi-colored setae (widespread in North America)............................................................ 9

9(8). Body unicolorous pale orange-brown, at most with T6 largely blackened and/or legs and antennae at most darkened apically; T3–6 setae mostly blackish ( Figs 22, 23 , 28, 29 ; southwestern USA and northwestern Mexico).............................................................................................. L. cirrhomeris Pitts & Manley, 2004

- Body generally darker, variegated with orange, brown, and blackish, legs and antennae variably blackened; T3–6 with interspersed silvery and blackish setae ( Figs 24–26 , 30–32 ; widespread in North America)............ L. hicksi Mickel, 1936

10(7). Mesosoma elongate, thoracic length subequal to width; mesosomal areolations deep and distinct, with all intervals distinct; frons mostly with complete areolations ( Figs 4 , 8 ; Madrean Archipelago in Arizona)........... L. osita Williams , sp. nov.

- Mesosoma not so elongate, thoracic length less than 0.9 × width; mesosomal areolations with margins less distinct and often partly obliterated; frons generally with obscure punctures and shallow rounded intervals (e.g. Figs 33–36 )............. 11

11(10). T2 sculpture mostly smooth between punctures (microreticulations not visible at 30 × magnification, obscure apparent reticulations sometimes visible at> 80 × magnification); dorsal bristles of mesonotum and T2 blackish, many bristles nearly as long as scape ( Figs 35 , 39 ; Central Valley and Coast Ranges, California).................... L. powelli ( Mickel), 1964

- T2 sculpture generally microreticulate between punctures (visible at 30 × magnification); if microreticulations obscure, then dorsal bristles of mesonotum and T2 mostly brown or yellowish, generally much shorter than scape (arid and semi-arid habitats South or East of Sierra Nevada and related ranges)...................................................... 12

12(11). Antennae and forelegs entirely blackish, middle and hind legs mostly black ( Figs 33 , 37 ; Baja California Sur).................................................................................... L. hedera Williams & Pitts, 2009

- Antennae and legs largely orange-brown, at least scape and fore coxa lighter brown ( Figs 34, 36 , 38, 40 ).............. 11

13(12). Body orange-brown, at most with T6 blackened ( Figs 34 , 38 ; Mojave and Sonoran Deserts in California and Arizona).......................................................................... L. beadugrimi ( Pitts & Manley, 2004)

- Femora and T2–5 variably darkened brown, in part clearly darker than orange-brown mesosoma ( Figs 36 , 40 ; Colorado Plateau and Sonoran Desert in Arizona).............................................. L. warneri Williams , sp. nov.

Figures

FIGURES 1–4. Lomachaeta females; dorsal habitus. 1) L. argenta; 2) L. vacamuerta, LaSalle County, Texas; 3) L. vacamuerta, Kennedy County, Texas; 4) L. osita, sp. nov. Scale bar = 1 mm.

FIGURES 9–14. Lomachaeta females; dorsal habitus. 9) L. hyphantria, Brazil; 10) L. hyphantria, Venezuela; 11) L. ibarrai, Holotype; 12) L. meloi, sp. nov.; 13) L. vianai, Argentina, Holotype; 14) L. vianai, Paraguay. Scale bar = 1 mm.

FIGURES 21–26. Lomachaeta females; dorsal habitus. 21) L. chionothrix; 22) L. cirrhomeris, California; 23) L. cirrhomeris, Arizona; 24) L. hicksi, Alachua Co., Florida; 25) L. hicksi, Coconino Co., Arizona; 26) L. hicksi, Cache Co., Utah. Scale bar = 1 mm.

FIGURES 33–36. Lomachaeta females; dorsal habitus. 33) L. hedera; 34) L. beadugrimi; 35) L. powelli; 36) L. warneri, sp. nov. Scale bar = 1 mm.

FIGURES 5–8. Lomachaeta females; lateral habitus. 5) L. argenta; 6) L. vacamuerta, Kennedy County, Texas; 7) L. vacamuerta, LaSalle County, Texas; 8) L. osita, sp. nov. Scale bar = 1 mm.

FIGURES 15–20. Lomachaeta females; lateral habitus. 15) L. hyphantria, Brazil; 16) L. hyphantria, Venezuela; 17) L. ibarrai, Holotype; 18) L. meloi, sp. nov.; 19) L. vianai, Argentina, Holotype; 20) L. vianai, Paraguay. Scale bar = 1 mm.

FIGURES 65–72. Lomachaeta line drawings: female mandible (65, 66), male genitalia, lateral view (67, 69, 71), penis valve, lateral view (68, 70, 72). 65) L. hicksi; 66) L. beadugrimi; 67–68) L. calamondin, sp. nov.; 69–70) L. eironeia, sp. nov.; 71–72) L. juanita, sp. nov.

FIGURES 27–32. Lomachaeta females; lateral habitus. 27) L. chionothrix; 28) L. cirrhomeris, California; 29) L. cirrhomeris, Arizona; 30) L. hicksi, Coconino Co., Arizona; 31) L. hicksi, Alachua Co., Florida; 32) L. hicksi, Cache Co., Utah. Scale bar = 1 mm.

FIGURES 37–40. Lomachaeta females; lateral habitus. 37) L. hedera; 38) L. beadugrimi; 39) L. powelli; 40) L. warneri, sp. nov. Scale bar = 1 mm.