Ommatius: synonyms, new record, redescription of Ommatius erythropus and description of the female of Ommatius trifidus (Diptera: Asilidae: Ommatiinae)

Sheila Lima; Rodrigo Vieira; Alexssandro Camargo; Cínthia Chagas

doi:10.3897/zoologia.34.e20784

Abstract

Ommatius erythropus Schiner, 1867 is redescribed and a lectotype is established. The female of Ommatius trifidus Vieira, Bravo & Rafael, 2010 is described and a new record is provided. Ommatius ruficaudus Curran, 1928 is established as a new synonym of Ommatius pulcher (Engel, 1885). An identification key is presented to the Ommatius costatus species group. A map with the geographic records is provided.

Key words

Brachycera, costatus group, Neotropical, normus group

Introduction

Ommatiinae Hardy, 1927, one of the 14 subfamilies of Asilidae, is characterized by the setae on the anterior surface of the antennal stylus (Dikow 2009). The most species-rich genus of Ommatiinae is Ommatius Wiedemann, 1821. Ommatius has wide geographic distribution, and is currently broadly defined by the character states of the subfamily (Scarbrough 2005), being the only included genus occurring in the Neotropical Region. Currently, there are 318 valid species in the world (Vieira 2015), 118 of which are from the Neotropics (Papavero 2009, Vieira 2015).

The New World species of Ommatius are divided into eight species groups (ampliatus and holosericeus (holosericeus complex), costatus, hanebrinki, lucidatus, normus, pumilus and tibialis) (Scarbrough 1990, 1993, 2000, 2002, 2008, Scarbrough and Perez-Gelabert 2006). The normus species group is currently restricted to South America, occurring in Venezuela, Guyana, Suriname, French Guiana, Brazil and Paraguay (Scarbrough 2008, Vieira et al. 2010), while the costatus species group is more widely distributed in the Neotropical Region. Males of the Ommatius costatus species group can be recognized by the presence of a long, thin, preapical, dorsoposterior seta on the mid femora; additionally, veins M₁ and M₂ are slightly sigmoid (Scarbrough 1993). The Ommatius normus species group is characterized mainly by the swollen hind femora, usually < 4.5 times longer than wide in anterior view, row of posteroventral bristles on the femur divided into basal and apical groups, separated by a wide bare space; epandrium with 2–3 long setae or macrosetae laterally; base of m1 narrow, at most 1/2 as wide as diameter at basal 1/3; distiphallus usually horizontal, only slightly depressed or elevated, tubular, wide in cross-section apically; spermathecae usually 3–5 times longer than wide, often strongly constricted medially (Scarbrough 2008).

Material and methods

This study is based on the examination of specimens borrowed from the following institutions: AMNH – American Museum of Natural History, New York, USA; DZUP – Coleção Entomológica Padre Jesus Santiago Moure, Curitiba, Brazil; INPA – Coleção de Invertebrados do Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil; MNRJ – Museu Nacional, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; MPEG – Museu Paraense Emílio Goeldi, Belém, Brazil; MZUEFS – Coleção Entomológica Professor Johann Becker, Museu de Zoologia da Universidade Estadual de Feira de Santana, Feira de Santana, Brazil; MZSP – Museu de Zoologia da Universidade de São Paulo, São Paulo, Brazil; NHM – Natural History Museum, London, UK; NMW – Naturhistorisches Museum, Vienna, Austria.

The morphological terminology follows Cumming and Wood (2009). The techniques of Vieira (2012) were used to examine the terminalia. Photographs of the specimens were taken with a Leica DFC500 digital camera attached to a Leica M205C stereomicroscope, connected to a computer with the Leica Application Suite LAS V3.6 software, which includes an Auto-Montage module (Syncroscopy software). After examination and illustration, the detached parts were stored in microvials with glycerin and pinned with their respective specimen. The label data are cited in full, with the original spelling, punctuation and dates. Information presented within square brackets are complementary data not included in the labels. Data from the same specimen but from different labels are separated by slashes (/). The distribution map was generated on the website SimpleMappr. Geographical coordinates were obtained from specimen labels. If they were not available, approximate coordinates were obtained from gazetteers and maps.

Taxonomy

Two treatments are proposed to the normus group: the female of Ommatius trifidus Vieira, Bravo & Rafael, 2010 is described and a new record is provided, and O. ruficaudus Curran, 1928 is established as a new synonym of O. pulcher (Engel, 1885). Ommatius erythropus Schiner, 1867 is redescribed and a lectotype is established. Furthermore, O. erythropus Schiner is allocated in the O. costatus species group. A map with the geographic records of the species, including those of the synonym O. ruficaudus Curran, is provided (Fig. 1).

Figure 1.

Geographic records of (n) Ommatius trifidus, () O. pulcher and (p) O. ruficaudus syn. nov.

Ommatius Wiedemann, 1821

Ommatius Wiedemann, 1821: 213.

Type-species

Asilus marginellus Fabricius, 1781 (sub. des., Coquillett, 1910: 579).

Ommatius costatus species group

Ommatius erythropus Schiner, 1867

Figs 2–8, 9–14

Ommatius erythropus Schiner, 1867: 411; Williston 1891: 90 (catalogue); Kertész 1909: 308 (catalogue); Carrera and Vulcano 1961: 77 (prey); Hull 1962 (2): 435; Martin and Papavero 1970: 59 (catalogue); Papavero 2009: 49 (catalogue).

Ommatinus erythropus; Engel 1930: 464, fig. 5.

Diagnosis

Abdomen spatulate (Fig. 6); 12 very fine yellow apical marginal scutellar setae; epandrium strongly turned down apically (Figs 10, 11, 12); hypandrium with acuminate projection with long yellow setae (Figs 10, 11, 13).

Redescription

Male. Lectotype here designated. Head (Fig. 4). Antenna dark brown (Figs 3, 5), scape with yellow setae, pedicel with black setae; palpus brown, yellow setose; proboscis dark brown, yellow setose ventrally, labial setae yellow; occiput black, silver tomentose with white setae; 8–12 black postocular macrosetae.

Thorax (Figs 2, 3, 5). Antepronotum and postpronotum black with white setae, yellow tomentose; mesonotum with ground color black dorsally, brown and yellow tomentose; posthumeral and postalar spots, lateroscutal stripes and pleuron silver tomentose, scutellum yellow tomentose. Chaetotaxy: 1 black and 1 yellow notopleural macrosetae; 1 yellow supra-alar macroseta; 1 yellow postalar macroseta; anatergal setae absent; 6 yellow dorsocentral macrosetae, 12 very fine yellow apical scutellar setae; katatergal macrosetae yellow; posterior meron + metanepisternum yellow tomentose, with row of yellow macrosetae and tuft of small yellow setae on posterior margin.

Wing (Figs 6, 7). Brown hyaline; dark brown veins; with costal dilatation; crossvein r-m just before middle of cell d; R₄₊₅ bifurcation at level of apex of cell d; microtrichia on posterior wing margin arranged in single row; halter pale yellow, stalk base and bulb light brown.

Legs (Figs 2, 8). Femora orange-yellow, apex brown; tibia yellow; hind tibia with brown apex; tarsomeres brown, except first tarsomere of fore and mid tarsi yellowish. Chaetotaxy: fore femur yellowish setose ventrally, apex with 2 black setae; mid femur yellow setose, with 3 black and 2 yellow macrosetae anterodorsally, 2 black setae dorsoapically; right hind femur with setae as follows: 9 macrosetae anteroventrally – 5 black apically, 1 yellow and 1 black medially, 2 yellow basally; 10 yellow small stout setae posteroventrally; 3 yellow macrosetae posterodorsally; 2 yellow and 2 black setae dorsoapically; left hind femur with 2 basal yellow setae posteroventrally and 7 black macrosetae posteroventrally; 4 yellow macrosetae anterodorsally; fore tibia with 3 long yellow setae posteriorly; mid tibia with 2 black ventral setae, 2 yellow posteroventral and 2 yellow anterodorsal setae; hind tibia with 4 black setae dorsoapically; tarsomeres largely black setose dorsally and yellow setose ventrally, first and third tarsomere of fore leg with 2 yellow setae, second tarsomere with 1 yellow seta.

Abdomen (Fig. 6). Brown. Spatulate; yellow setulose, densely pale yellow tomentose, posterior margin of tergites light brown and without setulae; tergites with yellow, lateral marginal macrosetae, longer on lateral margins of tergites I and III; two lateral macrosetae on tergites IV–IX.

Terminalia (Figs 9–13). Black, except for light brown cercus, gonocoxite and epandrium. Cercus truncate (Fig. 9); epandrium strongly turned down apically (Figs 10, 11, 12); epandrium with subapical projection and pointed apex (Figs 9, 10, 12); hypandrium with acuminate projection with long yellow setae (Figs 10, 11, 13); gonocoxite with digitiform projection at lateral margin (Fig. 13).

Remarks

Ommatius erythropus is a typical species of the O. costatus species group. It has the following characteristics of this group: preapical, dorsoposterior seta on the mid femora; hind femora more slender, usually 5–6 times longer than wide in anterior view, row of posteroventral bristles not divided into two groups or separated by wide bare space; M₁ and M₂ veins slightly sigmoid (Scarbrough 1993, 2008). Ommatius erythropus is similar to O. spatulatus Curran, 1928, but differs by the presence of six yellow dorsocentral macrosetae, apical scutellar yellow setae and mid femur with a brown, moderately thick, preapical, dorsoposterior seta. By contrast, O. spatulatus does not have dorsocentral macrosetae, apical scutellar setae and the mid femur has a pale, long, thin, preapical, dorsoposterior seta. Furthermore, O. erythropus differs from O. spatulatus by the combined characters of the terminalia.

Lectotype condition

Thorax with a hole on posterior portion of scutum.

Type examined

Lectotype: Savañah/erythropus, Coll. Winthem/Lectotype Ommatius erythropus. 1 male (NMW).

Paralectotype

Savañah/Coll. Winthem. 1 male (NMW).

Figures 2–8.

Ommatius erythropus, lectotype male: (2) habitus, lateral view; (3) head and thorax, lateral view; (4) head, frontal view; (5) head and thorax, dorsal view; (6) abdomen, dorsal view; (7) wing; (8) hind femora, lateral view. Scale bars: 1.0 mm.

Figures 9–14.

Ommatius erythropus, lectotype male: (9) terminalia, dorsal view; (10) epandrium, posterior view; (11) terminalia, posterior view; (12) terminalia, lateral view; (13) terminalia, ventral view; (14) labels. Scale bars: 0.5 mm.

Ommatius normus species group

Ommatius pulcher (Engel, 1885)

Figs 15, 16

Emphysomera pulchra Engel, 1885:146.

Ommatius (Emphysomera) pulchra; Bromley 1946: 112 (catalogue).

Ommatius pulchra; Curran 1928: 1; Scarbrough 1990: 66; Vieira et al. 2005: 19.

Ommatius pulcher; Martin and Papavero 1970 (35b): 60 (catalogue); Scarbrough 2008: 8, figs 4, 33–41; Papavero 2009: 51 (catalogue); Vieira et al. 2010: 44.

Ommatius ruficauda Curran, 1928: 2; Bromley 1946: 112 (catalogue); Hull 1962 (2): 435; Martin and Papavero 1970: 59 (catalogue); Papavero 2009: 51 (catalogue), syn. nov. (Figs 17–30).

Ommatius ruficaudus; Scarbrough 2008: 11, fig. 5; Vieira et al. 2010: 47. syn. nov. (Figs 17–30).

Remarks

Scarbrough (2008) and Vieira et al. (2010) commented on the similarity between O. pulcher (Figs 15, 16) and O. ruficaudus (Figs 17–30). After studying the type material of O. ruficaudus (Figs 17–30), we observed that, although the bodies of the specimens are covered with fungi, the male terminalia of O. ruficaudus and the illustrations of O. pulcher are essentially identical. Furthermore, Curran (1928) separated the two species by the coloration of genitalia of both sexes, reddish and shinning black, respectively. In O. pulcher and O. ruficaudus the apical scutellar setae are absent and both have the clavate abdomen. Vieira et al. (2010) mentioned that the type-locality of O. ruficaudus is Chapada dos Guimarães (Brazil) and Scarbrough (2008) wrote that additional specimens of this species have not been located. We found nine specimens that were collected at the type-locality during the SISBIOTA – Diptera project. These specimens were identified as O. pulcher. Thus, after the combination of data from distinct sources, O. ruficaudus is established as a new synonym of O. pulcher.

Holotype condition

Body largely covered with fungi, postpedicel on both antennae lost, head partially damaged, left mid leg and left hind tibia lost.

Geographical records

Brazil: Pará, Rondônia, Alagoas, Bahia, Mato Grosso, Distrito Federal, Goiás, Minas Gerais, Mato Grosso do Sul, Rio de Janeiro, São Paulo, Paraná and Santa Catarina; Paraguay.

Type examined

Holotype: Ommatius ruficauda Curran Holotype/Chapada [dos Guimarães – Mato Grosso, BRAZIL] [15°26’57.6”S 55°46’12.1”W]/S.W. Williston Collection. 1 male (AMNH).

Paratype: Same data as holotype, except: Allotype ♀. 1 female (AMNH).

Additional material examined

Brasil. Pará: Oriximiná [01°45’56”S 55°51’58”W], 1 female (MZSP); Rondônia: Vilhena [12°44’26”S 60°08’45”W], 1 male, 1 female (DZUP); Alagoas: Mangabeira [9°38’46.2”S 35°42’51.1”W], 1 female (MZSP); Mato Grosso: Chap.[ada] Guimarães [15°26’57.6”S 55°46’12.1”W], 1 female (DZUP); Chap.[ada] Guimarães (12°50’S 51°47’W), 1 female (MZSP); Chap.[ada] Guimarães (12°50’S 51°45’W), 2 males (NHM); Chap.[ada] dos Guimarães (15°24’33.5”S 55°49’59.0”W), 5 males, 2 females (MZSP); Chap.[ada] dos Guimarães (15°26’10.7”S 55°47’22.9”W), 1 female (MZSP); Chap.[ada] dos Guimarães, (15°24’21.8”S 55°50’97”W), 1 male (MZSP); Mato Grosso do Sul: Aquidauana (20°26’07,2”S 55°39’32.8”W), 1 female (MZSP); Bahia: Cachoeira (Faz.[enda] Vila Rial) [12°35’44.8”S 38°54’01.6”W], 1 male (MZUEFS); Distrito Federal: Brasília [15°46’48”S 47°55’45”W], 1 male, 2 females (MZSP); Goiás: (no locality), 3 females (DZUP); Catalão [18°09’57”S 47°56’35”W], 1 female (DZUP); Campinas [Goiânia] [16°40’16.9”S 49°17’38.0”W], 1 female (MNRJ), 2 males, 4 females (MZSP); Corumbá [de Goiás][15°55’30”S 48°48’43”W] (F.[azenda] Monjolinho), 2 males, 1 female (MZSP); Corumbá [de Goiás], 1 female (MZSP); Anápolis [16°19’42”S 48°57’06”W], 1 female (MZSP); Minas Gerais: Barbacena [21°13’20”S 43°46’16”W], 4 males, 18 (DZUP); Passos [20°43’23”S 46°36’43”W], 2 males (DZUP); Poços de Caldas [21°47’08”S 46°34’01”W] (Retiro dos Carneiros), 3 males, 2 females (MNRJ); Poços de Caldas (Morro de Ferro) [21°55’S 46°31’W], 1 female (MNRJ); Poços de Caldas (Campo do Saco), 3 males, 3 females (MNRJ); Poços de Caldas (Alto da Santa Cruz), 2 females (MNRJ); Poços de Caldas (Alto do Selado), 1 female (MNRJ); S.[erra] do Cipó (Santana do Riacho) [19°20’41.2”S 43°38’26.9”W], 2 males, 1 female (MNRJ); Ibiá [19°29’09”S 46°32’41”W], 1 male(DZUP); Belo Horizonte, 1 male, 1 female (MZSP), Varginha [21°33’25”S 45°26’37”W], 1 female (MZSP); Mato Grosso do Sul: Caarogó [Caaropó] [22°37’57”S 54°49’23”W] (Faz.[enda] Pai Cué), 1 male (MZSP); Três Lagoas (marg.[em] esq.[uerda] rio Sucuriu) [20°32’25.8”S 51°50’57.9”W], 1 female (MZSP); Três Lagoas [20°47’11”S 51°41’52”W] (Faz.[enda] Floresta), 1 male (MZSP); Maracajú [21°36’39”S 55°09’58”W], 1 female (MZSP); São Paulo: Severínia [20°48’19”S 48°48’32”W], 14 males, 12 females (MZSP); Sumaré [22°49’20”S 47°16’23”W], 3 males, 2 females (MZSP); Ribeirão Preto [21°10’15”S 47°48’06”W] (Rio Tamanduá), 7 males, 13 females (MZSP); Ribeirão Preto (Faz.[enda] Monte Alegre), 1 male (MZSP); Rib.[eirão Preto], 1 female (DZUP); Campinas [22°54’51”S 47°04’38”W], 1 male (MZSP); M.[ogi] das Cruzes [23°31’20”S 46°11’25”W], 13 males, 7 females (MZSP); Tamoio, 3 males, 3 females (MZSP); Cajuru (Coqueiros) [21°16’30”S 47°18’04”W], 1 male, 4 females (MZSP); Batatais [20°53’39”S 47°35’26”W], 25 males, 25 females (MZSP), 1 male (DZUP); Araraquara [21°47’06”S 48°10’35”W], 1 male (MZSP); Juquiá [24°19’06”S 47°38’06”W], 1 female (MZSP); Pontal [21°01’42”S 48°02’08”W], 1 female (MZSP); Guatapará [21°29’41”S 48°02’07”W], 2 females (MZSP); Mairiporã [23°19’17”S 46°34’32”W], 1 (MZSP); Jundiaí [23°11’09”S 46°53’34”W], 1 male (MZSP); Salesópolis (Est.[ação] Biol.[ógica] Boracéia) [23°37’51”S 45°52’11”W], 1 male (MZSP); São Paulo [23°32’50”S 46°38’09”W], 9 males, 15 females (MZSP); Poá [23°32’01”S 46°20’54”W], 1 male, 1 female (MZSP); Rio Claro [22°24’58”S 47°33’25”W], 9 males, 18 females (MZSP); Onda Verde [20°36’00”S 49°17’43”W](Faz.[enda] São João), 2 males, 10 females (MZSP); Barueri [23°30’47.8”S 46°52’22.5”W], 2 males, 1 female (MZSP); Paraná: Ponta Grossa [25°04’51”S 50°09’20”W], 1 male (DZUP); [Ponta Grossa] ([Parque] Vila Velha) [25°14’45.1”S 50°00’19.5”W], 2 females (DZUP); Curitiba [25°25’57”S 49°16’19”W], 1 male, 1 female (DZUP), 1 male (MZSP); Laranjeira do Sul [25°24’22”S 52°24’50”W], 1 female (DZUP).

Figures 15–16.

Ommatius pulcher, male: (15) habitus, dorsal view; (16) habitus, lateral view. Scale bars: 1.0 mm.

Figures 17–23.

Ommatius ruficaudus syn. nov., holotype male: (17) habitus, lateral view, (18) head and thorax, lateral view; (19) head, frontal view; (20) wing; (21) head and thorax, dorsal view; (22) terminalia, posterior view; (23) labels. Scale bars: 17, 20 = 2 mm, 18, 19, 21, 22 = 1.0 mm.

Figures 24–30.

Ommatius ruficaudus syn. nov., holotype female: (24) habitus, lateral view; (25) head and thorax, lateral view; (26) head, frontal view; (27) wing; (28) head and thorax, dorsal view; (29) terminalia, posterior view; (30) labels. Scale bars: 20-28 = 2.0 mm, 29 = 1.0 mm.

Ommatius trifidus Vieira, Bravo & Rafael, 2010

Figs 31–35

Ommatius trifidus Vieira, Bravo & Rafael, 2010: 47.

Description

Female. Head. Antenna black, scape and pedicel with black setae; palpus black, yellow setose; proboscis black, yellow setose ventrally, labial setae yellow; occiput black, yellow tomentose with whitish setae; 8 black postocular macrosetae.

Thorax. Antepronotum and postpronotum black with white setae; mesonotum black dorsally, brown and yellow tomentose; posthumeral spot, lateroscutal stripes and pleuron silver and yellow tomentose; scutellum yellow tomentose. Chaetotaxy: 2 notopleural macrosetae; 1 supraalar macroseta; 1 postalar macroseta; anatergal setae absent; 4 dorsocentral macrosetae; 2 black marginal scutellar macrosetae; discal scutellar setae yellow; katatergal macrosetae yellow; posterior meron + metanepisternum with row of yellow macrosetae and tuft of small yellow setae on posterior margin, silver tomentose.

Wing. Hyaline; black veins; without costal dilatation; crossvein r-m after middle of cell d; R4+5 bifurcation at level of apex of cell d; microtrichia on posterior wing margin arranged in single row; halter light brown.

Legs (Fig. 32). Fore and mid femora dark brown dorsally and orange-yellow ventrally, hind femora dark brown, orange-yellow basally; tibia yellow; tarsomeres dark brown. Chaetotaxy: fore femur yellow setose; mid femur yellow setose, with 4 black setae posterodorsally; right hind femur with setae as follows: 6 black setae posteroventrally, 2 black setae posterodorsally; fore tibia largely yellow setose, with 1 long black posteroventral seta; mid tibia with long black and yellow setae; hind tibia with 6 long black setae dorsally.

Abdomen. Black, yellow setulose, white tomentose, posterior margin of tergites light brown; tergites I–II with yellow, lateral, marginal macrosetae; black sternites.

Terminalia. Apical margin of sternite VIII slightly produced (Fig. 34); tergite IX + X short dorsally (Fig. 33); apical margin of cercus subtruncate (Fig. 33); basal half of spermathecae narrower than apical half with ripples at lateral margins (Fig. 35).

Type examined

Holotype male, Brazil, Pará: Bujaru [01°30’54”S 48°02’41”W], 12.v.1978/BRASIL, Pará, I.S. Gorayeb [Collector]/Holótipo Ommatius trifidus Vieira, Bravo and Rafael (MPEG).

Paratypes: Brasil, Pará: Belém (MPEG-CAMPUS) [1°27’03”S 48°26’44”W], 1 male, 21.vi.1993, L. Costa [Collector] (MPEG); Tucuruí, Rio Tocantins, Marg.[em] Direita Canoal [4°00’48.6”S 49°45’37.8”W], 26–28.iii.1984/Armadilha Suspensa/Brasil, Pará, T. Pimentel 1 male (MPEG); Bôa [Boa], Vista, mu.[nicípio] Castanhal [1°17’53.7”S 47°55’00.5”W], 3.iii.1964/BRASIL, PA[rá], W. França Col. 1 male (MZSP); [Rodovia] Belém-Brasília, Km 90 [16°11’22.9”S 49°02’08.3”W], F.S. Antonio, 30.vii.1972/BRASIL, PA[rá], M. Helana Col. 1 male (MZSP); Bahia: Seabra [12°25’07”S 41°46’13”W], 11–13.i.2008. Leg Alvim, E./Armadilha Luminosa/MZUEFS# 38363 1 male (MZUEFS); Barreiras, APA Rio de Janeiro [11°53’23.9”S 45°35’46.7”W], 05.iv.2008, Bravo, F., Menezes, E., Alvim, E., Silva-Neto, A. [Collectors]/MZUEFS #39217 1 male (MZUEFS).

Additional material examined

Brazil, Maranhão: Caxias [04°51’32”S 43°21’22”W] (Fazenda Frexeira), 4 females; Caxias (Res.[erva] Ecol.[ógica] Inhamum) [04°53’30”S 43°24’53”W], (1 female).

Geographical records

Brazil: Pará, Maranhão (new record) and Bahia.

Remarks

The spermathecae of O. trifidus Vieira, Bravo and Rafael is very similar to O. normus Curran. However, in O. trifidus the basal half of the spermathecae is narrower than the apical half with ripples at the lateral margins, while in O. normus the apical 1/3 of the spermathecae is wider than the basal 2/3, with the two areas separated by a strong constriction (Scarbrough 2008).

Figures 31–35.

Ommatius trifidus: (31) male habitus, lateral view; (32) female habitus, lateral view; (33) tergite IX+X and cercus, dorsal view; (34) sternite VIII; (35) sternite VIII and spermathecae. Scale bars: 31, 32 = 3.0 mm, 33-35 = 0.5 mm.

Identification key to males of the Ommatius costatus species group (modified from Scarbrough 1993)

1	Mid femur with brown, moderately thick, preapical, dorsoposterior seta	2
1’	Mid femur with pale, long, thin, preapical, dorsoposterior seta	5
2	Apical scutellar macrosetae present; hind tibia with short, thick apical macroseta anteriorly; epandrium narrow apically, much narrower than medially (Brazil, Colombia, Peru)	O. uncatus Scarbrough, 1993
2’	Apical scutellar setae absent, if present, short; hind tibia with only short slender apical setae anteriorly; epandrium about as wide apically as medially	3
3	Epandrium strongly turned down apically (Figs 10, 12) (South America)	O. erythropus Schiner, 1867
3’	Epandrium straight apically	4
4	Vein R₄ at or just below wing apex; epandrium short, 2 times longer than wide, ventral corner rotated basally and strongly curved ventrally; gonostylus narrow, about 1/6 as wide as long medially (Brazil)	O. tractus Scarbrough, 2007
4’	Vein R₄ above wing apex; epandrium longer, 3 times as long as wide, ventral corner simple, not as above; gonostylus much wider, 1/3-1/2 as wide as long medially (Mexico, Costa Rica)	O. incurvatus Scarbrough, 1993
5	Gonostylus flat in cross-section, wide in lateral view	6
5’	Gonostylus usually oval to round in cross-section, narrow in lateral view	10
6	Epandrium with subapex strongly constricted, apex flared and wider than subapex; gonocoxite with flat, elongate process (Costa Rica, Panama, southern Lesser Antilles, South America)	O. orenoquensis Bigot, 1876
6’	Epandrium without subapical constriction, apex usually pointed; gonocoxite without unusually flat, elongate process	7
7	Hypandrium with dense pad of pile apically or with transverse cluster of setae medially	8
7’	Hypandrium without pad of pile or cluster of setae	11
8	Hypandrium with dense pad of pile apically; apex of epandrium broadly rounded; aedeagus slightly recurved apically (Cuba)	O. piliferous Scarbrough, 1985
8’	Hypandrium with only transverse cluster of setae medially; apex of epandrium pointed; aedeagus not recurved apically	9
9	Medioapical margin of hypandrium with long thick spine; apical 1/3 of epandrium wide, not unusually narrow or toothlike (Bolivia, Brazil, Ecuador, Peru)	O. spinosus Scarbrough, 1993
9’	Medioapical margin of hypandrium without long thick spine; apical 1/3 of epandrium acutely pointed, toothlike (Brazil)	O. dentatus Scarbrough, 1993
10	Pleuron yellowish tomentose; base of distiphallus cordiform in apical profile, base abruptly angled downward and without prominent vertical flanges dorsally (Ecuador, Mesoamerica, Mexico)	O. humatus Scarbrough, 1993
10’	Pleuron whitish tomentose; base of distiphallus oval, convex with 2 prominent vertical flanges dorsally (Jamaica)	O. oreophilus Farr, 1965
11	Hind tibia apically with short, thick, spurlike macroseta	12
11’	Hind tibia apically without short, thick, spurlike macroseta; epandrium with flat, leaflike process (Brazil)	O. didymus Scarbrough, 1993
12	Epandrium flared apically, width of apex greater than subapex	13
12’	Epandrium pointed apically, width of apex less than subapex	16
13	Two or more apical scutellar macrosetae	14
13’	Apical scutellar macrosetae absent	15
14	Hind femur swollen; epandrium strongly curved behind terminalia, with short spinelike process subapically (Belize, El Salvador, Guatemala, Mexico)	O. amula Curran, 1982
14	Hind femur not unusually swollen; epandrium only slightly angled behind terminalia, with strong spinelike process dorsally (Tobago Island, South America southward to Argentina)	O. costatus Rondani, 1850
15	Dorsocentral setae absent; abdomen spatulate (Brazil, Argentina)	O. spatulatus Curran, 1928
15’	Three-four dorsocentral setae; abdomen not spatulate (Mexico)	O. achaetus Scarbrough, 1993
16	Ventral margin of epandrium with flat, thin, rectangular process	O. complanatus Scarbrough, 1993
16’	Ventral margin of epandrium without flat, thin, rectangular process (Jamaica)	O. alexanderi Farr, 1965

Acknowledgments

We thank Fundação de Amparo à Pesquisa do Estado do Amazonas (FAPEAM) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for the PRONEX project, Edital 016/2006, Proc. 1437/2007, CNPq Process 401.243/2012–5, FAPEAM EDITAL 022/2013–FIXAM/AM Process 062.00745/2014 and FAPEAM edital 21/2011. Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) (Grant 2010/52314-0) for the support to the SISBIOTA Brazil Program. We also thank the curators of the following museums for the loan of specimens: David Grimaldi (AMNH), Luciene Marinoni (DZUP); Márcia Couri (MNRJ), Marcio Oliveira (INPA), Orlando Silveira (MPEG), Carlos Lamas (MZSP), Freddy Bravo (MZUEFS), Erica McAlister (NHM), and Peter Sehnal (NMW). Courtney Richenbacher (AMNH) for the photographs of Ommatius ruficaudus type-specimens and Lisiane Wendt (UFPR) for curating the Ommatius erythropus holotype. Anonymous reviewers made comments that improved the manuscript. CNPq and CAPES provided fellowships that allowed us to complete this work.

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