Euglossa (Euglossella) singularis Mocsary

Hinojosa-Diaz, Ismael A. & Engel, Michael S., 2011, Revision of the orchid bee subgenus Euglossella (Hymenoptera, Apidae), Part I, The decorata species group, ZooKeys 140, pp. 27-69 : 47-51

Euglossa (Euglossella) singularis Mocsary Figs 47-56

Euglossa singularis Mocsáry in Friese, 1899: 169. Holotype ♀ (HNHM, visum).

Euglossa decorata ruficauda Cockerell, 1918: 688. Holotype ♀ (AMNH, visum), syn. n.

Material examined.

Brazil: "SERRA do NAVIO; Terr. Amapá BRASIL; K. Lenko leg. // COLECÃO; CAMPOS SEABRA" (1♂) FLMNH.

French Guiana: "FRENCH GUIANA; Saül, Mt. Galbao Summit, 740 m; 3°37'18"N, 53°16'42"W; 6 JUN 1997; J.Ashe, R.Brooks; FG1AB97 152 // Euglossa; decorata F. Smith 1874 ♀ [sex handwritten]; det. R.W. Brooks 1998 // [bar code];SM0103108; KUNHM-ENT" (1♀) SEMC; "FRENCH GUIANA; 19 km. SW. Kourou;16 July 1977. C.D.; Michener, T.Kukuk" (1♀) SEMC; "FRENCH GUIANA; Kourou, Km. 17 SW. [number handwritten]; 20Feb77; D. Roubik.No.91" (1♀) FLMNH; "FRENCH GUIANA; Kourou, Km. 16 SW. [number handwritten]; 13 April 1977 [date handwritten]; D. Roubik. No.127 // Euglossa ; decorata Smith; det. R.L. Dressler 1978 [last two digits handwritten]" (1♀) SEMC.

Guyana: "Kalacoon; Bartica District; British Guiana // TYPE [red label] // Am. Mus. Nat. Hist.; Dept. Invert. Zool.; No.24484 [number handwritten] // Trop. Research Station; New York Zool. Society; No.; ac: 531b [last line handwritten on underside] // Euglossa; decorata n [?]; ruficauda;Ckll. TYPE. [label handwritten]" (1♀) AMNH; "BRITISH GUIANA:; Kartabo, Bartica; Dist. 1920 [last two digits handwritten] // Trop. Research Station; New York Zool. Society; No.201122 [number handwritten] // Gift of New York; Zoo.Soc.,Dept.; Tropical Research; William Beebe. Dir // Euglossa; decorata ♀; var. ruficauda; Cockerell; Det. Schwarz // Comment on; intermixed; dark hairs on; thorax and; vertex; darker; scutellar cushion,; etc. [last two labels handwritten]" (1♀) AMNH; Kartabo; Bartica District; British Guiana; 17-III-1922 [month and day handwritten] // Gift of New York; Zoo.Soc.,Dept.; Tropical Research; William Beebe. Dir // // Euglossa; decorata ♀; var. ruficauda; Cockerell; Det. H.F. Schwarz [label handwritten] " (1♀) AMNH; "Dawa, Tapakuma; Pomeroon, Guyana; C.Dodson 3-27-1970 [day handwritten]; Vanillin // Euglossa; decorataSmith; det. R.L. Dressler 1968 [last digit handwritten]" (1♂) FLMNH; same collecting data, no identification label (1♂) FLMNH; same collection data except date missing the day (3♂♂); "Kamakusa; Brit.Guiana; H.Lang // Euglossa; singularis; Mocs.; Det. J.S.Moure 1957 [first three lines and last two digits of year handwritten]" (1♀) NHML.

Surinam: "Amer. mer.; Surinam // Euglossa TYPE [second word handwritten]; singularis Mocs.; det. R.L.Dressler, 1975 // [big red label with no writing]" (1♀) HNHM; "[small pink label with no writing] // Surinam [handwritten] // Euglossa; singularis; ♂ Mocs.; 1910 Friese det. [first three lines handwritten, third and fourth lines overlapped] // Am. Mus. Nat. Hist.; Dept. Invert. Zool.; No.26004 [number handwritten] // Head fell off; and was reattached; by I. Hinojosa-Díaz 2006 [all handwritten except for name and first three digits of year]" (1♂) AMNH.

Venezuela: "VENEZUELA: BO. [state acronym handwritten]; Icabaru [handwritten]; 25 II 1967 [handwritten except first three digits of year] // Euglossa;singularisMocs.; det. R.L. Dressler 1968 [last digit handwritten]" (1♂) FLMNH.

Diagnosis.

Labiomaxillary complex in repose barely reaching sixth metasomal sternum in the male, and posterior margin of third metasomal sternum in the female (Figs 48, 50); both sexes with posterior margin of mesoscutellum evenly convex (Figs 47, 49); integument of head and mesosoma of both sexes brown to dark brown, with coppery-green hue, greener on mesoscutum (Figs 47-52); malar area length on average 0.15 the basal mandibular width; male mesotibia with posterior and anterior tufts separated by a distinguishable gap, posterior tuft characteristically circular (Fig. 54); male metatibia scalene right triangular (forming a right or slightly obtuse angle at intersection of anterior and ventral margins) (Fig. 55); first metasomal tergum orange, second tergum orange anteriorly, brown on posterior third, remaining terga brown to dark brown, similar pattern on sterna (some specimens, especially females with all metasoma dark brown), entire metasoma with faint coppery hue; legs yellow to dark brown (Figs 48, 50, 53-56); lateral section of gonostylus with dorsal sector straight, not projected, ventral lobe apically acute.

Description.

♂: Structure. Total body length 10.81 mm (10.59-10.96; n=5); labiomaxillary complex in repose reaching anterior margin of sixth metasomal sternum (Fig. 48). Head length 2.73 mm (2.67-2.89; n=5), width 4.38 mm (4.22-4.48; n=5); upper interorbital distance 2.21 mm (2.19-2.22; n=5); lower interorbital distance 1.87 mm (1.81-1.93; n=5); upper clypeal width 1.01 mm (0.96-1.11; n=5); lower clypeal width 1.84 mm (1.78-1.89; n=5); clypeal protuberance 0.58 mm (0.44-0.67; n=5); clypeal ridges, labral ridges and labral windows as described for Euglossa aurantia ; labrum about as wide as long, length 0.98 mm (0.96-1.04; n=5), width 1.00 mm (0.93-1.04; n=5); interocellar distance 0.3 mm (n=5); ocellocular distance 0.70 mm (0.67-0.74; n=5); first flagellomere as long [0.45 mm (0.44-0.48; n=5)] as second and third flagellomeres combined [0.45 mm (0.44-0.48; n=5)]; length of malar area 0.10 mm (0.09-0.11; n=5). Mandible tridentate. Pronotal lateral angle as described for Euglossa aurantia ; intertegular distance 3.32 mm (3.19-3.41; n=5); mesoscutal length 2.62 mm (2.52-2.67; n=5); mesoscutellar length 1.27 mm (1.19-1.33; n=5); posterior margin of mesoscutellum evenly convex (Fig. 47); mesotibial length 2.13 mm (2.00-2.30; n=5); mesobasitarsal length 2.13 mm (2.20-2.30; n=5), width 0.62 mm (0.56-0.67; n=5); posterior keel as described for Euglossa aurantia ; metatibial shape scalene right triangular (forming a right or slightly obtuse angle at intersection of anterior and ventral margins) (Fig. 55), metatibial anterior margin length 3.19 mm (2.93-3.41; n=5), ventral margin length 1.97 mm (1.56-2.22; n=5), postero-dorsal margin length 3.90 mm (3.78-4.15; n=5), maximum metatibial thickness 1.19 mm (1.04-1.33; n=5); metatibial organ slit as described for Euglossa aurantia (Fig. 55); basal section of metatibial organ slit length 0.55 mm (0.48-0.67; n=5); metabasitarsal length 2.48 mm (2.37-2.59; n=5), mid-width 0.85 mm (0.44-0.59; n=5); metabasitarsal ventral border truncate. Forewing length 8.74 mm (8.07-9.26; n=5); jugal comb with 12-15 (n=5) blades; hind wing with 18-21 (n=5) hamuli. Maximum metasomal width 4.28 mm (4.07-4.44; n=5); second metasomal sternum integumental modifications as described for Euglossa aurantia .

Coloration. Head integument and ivory areas as describred for Euglossa decorata , except coppery iridescence dominant on clypeus (Fig. 51). Mesosoma as described for Euglossa decorata (Figs 47-48); legs yellow to dark brown, with a similar pattern as in Euglossa aurantia (Figs 48, 53-55); tegulae and wings as described for Euglossa aurantia (Figs 47-48). First metasomal tergum orange, second tergum orange anteriorly, brown on posterior third, remaining terga brown to dark brown, similar pattern on sterna (some specimens, specially females with all metasoma dark brown), all metasoma with faint coppery hue (Figs 47-48).

Sculpturing. As described for Euglossa aurantia .

Vestiture. General vestiture as described for Euglossa aurantia .

Terminalia. Hidden sterna and capsule as described for Euglossa apiformis , lateral section of gonostylus with a straight or slightly convex dorsal sector (Fig. 33).

♀: Structure. Total body length 10.92 mm (10.00-11.63; n=5); labiomaxillary complex in repose reaching posterior margin of third metasomal sternum (Fig. 50). Head length 2.78 mm (2.67-2.85; n=5); head width 4.53 mm (4.41-4.59; n=5); upper interorbital distance 2.37 mm (2.26-2.44; n=5); lower interorbital distance 2.06 mm (2.00-2.11; n=5); upper clypeal width 1.11 mm (1.11-1.13; n=5); lower clypeal width 1.99 mm (1.93-2.00; n=5); clypeal protuberance 0.59 mm (0.52-0.67; n=5); medial and paramedial clypeal ridges well developed; labrum about as wide as long, length 1.02 mm (0.96-1.05; n=5), width 1.08 mm (1.04-1.11; n=5); labral ridges and windows as in male; anterior edge of labrum arched outwards; interocellar distance 0.30 mm (0.30-0.31; n=5); ocellocular distance 0.74 mm (n=5); length of first flagellar article [0.43 mm (0.41-0.44; n=5)] almost equal to combined lengths of second and third flagellar articles [0.45 mm (0.44-0.48; n=5)]; length of malar area 0.11 mm (0.08-0.15; n=5). Mandible tridentate. Pronotal lateral angle as in male; intertegular distance 3.33 mm (3.26-3.41; n=5); mesoscutal length 2.63 mm (2.44-2.78; n=5); mesoscutellar length 1.26 mm (1.19-1.33; n=5); posterior border of mesoscutellum as in male (Fig. 49); mesotibial length 2.19 mm (2.07-2.30; n=5); mesobasitarsal length 2.02 mm (1.93-2.15; n=5), maximum width 0.63 mm (0.52-0.70; n=5); metatibia triangular; metatibial anterior margin length 3.01 mm (2.96-3.19; n=5); metatibial ventral margin length 1.74 mm (1.56-1.93; n=5); metatibial postero-dorsal margin length 3.39 mm (3.33-3.48; n=5). Forewing length 8.34 mm (8.00-8.59; n=5); hind wing with 20-21 hamuli. Maximum metasomal width 4.67 mm (4.59-4.74; n=5).

Coloration. In general as described for male. Paraocular marks absent; ivory coloration on mandible restricted to proximal one-third, antennal scape with yellow spot occupying most of antero-lateral surface although noticeably narrower than in male (Fig. 52).

Sculpturing. As described for male except mesepisternum with punctures not as dense (separated by about one puncture diameter).

Vestiture. As described for male (see comments); mesoscutellar tuft rhomboid, composed of dense, fulvous and/or brown (see comments), erect, thick, multibranched (branches minute) setae (Fig. 49). Other features as described for female of Euglossa aurantia .

Comments.

Within the variety of specimens examined in the present study, most of those that exhibited a darker coloration deviating from the orangish color of the Euglossa decorata type bore identification labels from several experts referring to them as Euglossa singularis . As was noted above for Euglossa decorata in which there is a range of color variation, including numerous intermediates, blending to very dark specimens, the same can be recognized for Euglossa singularis . Despite the fewer number of specimens of Euglossa singularis (as here recognized) available for this study, a similar (although not as extreme) variation of integumental coloration can be appreciated. The female holotype is the darkest of the specimens examined for this species, and the holotype of Euglossa decorata ruficauda is the lightest. All specimens examined, both male and female, are on average smaller than any other species in the decorata group and the males are easily recognizable by the shape of the mesotibial posterior tuft. The rather copperyclypeus added to the previous features, and the restriction of these specimens to the Guiana Shield region, makes Euglossa singularis a distinctive species, for which characterization should not rely solely on integumental color.