Euglossa (Euglossella) perfulgens Moure

Hinojosa-Díaz, Ismael A. & Engel, Michael S., 2014, Revision of the orchid bee subgenus Euglossella (Hymenoptera: Apidae), Part II: The viridis and mandibularis species groups, Journal of Melittology 36, pp. 1-108 : 94-99

Euglossa (Euglossella) perfulgens Moure

( Figs. 139–143 , 170 )

Euglossa (Euglossa) perfulgens Moure, 1967a: 388 [♀]. Holotype ♀ (DZUP, visum).

DIAGNOSIS: Labiomaxillary complex in repose reaching fourth metasomal sternum; lower interorbital distance about 1.20 times as wide as upper interorbital distance ( Fig. 141 ); malar area long (over 0.40 mm, twice as long as diameter of mid-flagellar articles) ( Figs. 141, 143 ); pronotal dorsolateral angle acute; mesoscutellar tuft, large, cordate slightly wider than long, occupying about one third of width and about three fourths of length of mesoscutellum, composed of dense, fulvous setae ( Fig. 139 ); metabasitarsus with anterior margin slightly convex and posterior margin straight ( Fig. 142 ); metasoma wider than head (about 1.07 times or over) ( Fig. 139 ); head amber-brown with strong golden-bronzy iridescence and green areas on margins and sulci ( Fig. 141 ); scape brown with no ivory coloration ( Fig. 141 ); mesosoma golden-bronzy with green coloration along margins and sulci/sutures (vide Description for variation, infra) ( Figs. 139–140 ); metasomal terga with strong bronzy-reddish coloration (vide Description for variation, infra) ( Fig. 139 ); mesoscutellum densely punctate (punctures separated by about half a puncture diameter) ( Fig. 139 ); central area of mesepisternum moderately densely punctate (punctures separated by one to one and a half puncture diameters); metasomal terga densely punctate with small, shallow punctures ( Fig. 139 ); mesosomal vestiture dominated by a mix of soft, fulvous and reddish-brown, sturdy setae ( Figs. 139–140 ).

DESCRIPTION: ♀: Structure. Total body length 13.61 mm (12.96–13.93; n=5); labiomaxillary complex in repose reaching fourth metasomal sternum ( Fig. 140 ). Head length 3.44 mm (3.30–3.70; n=5); head width 5.46 mm (5.39–5.56; n=5); upper interorbital distance 2.46 mm (2.37–2.52; n=5); lower interorbital distance 2.94 mm (2.85–3.01; n=5); upper clypeal width 1.45 mm (1.41–1.48; n=5); lower clypeal width 2.38 mm (2.33–2.41; n=5); clypeal protuberance 1.13 mm (1.04–1.26; n=5); clypeal ridges, labral ridges, and labral windows as in male of E. bigibba ; labrum rectangular, wider than long, length 1.25 mm (1.19–1.30; n=5), width 1.46 mm (1.41–1.52; n=5); anterior margin of labrum arched outwards with subapical carina ( Fig. 141 ); interocellar distance 0.37 mm (0.36–0.37; n=5); ocellocular distance 0.70 mm (0.67–0.74; n=5); first flagellar article longer [0.65 mm (0.63–0.67; n=5)] than second and third flagellar articles combined [0.53 mm (0.52–0.59; n=5)]; length of malar area 0.52 mm (0.44–0.59; n=5). Mandible tridentate. Pronotal dorsolateral angle acute; intertegular distance 4.30 mm (4.07–4.37; n=5); mesoscutal length 3.41 mm (3.33–3.56; n=5); mesoscutellar length 1.53 mm (1.48–1.56; n=5); posterior margin of mesoscutellum as described for male of E. bigibba ( Fig. 139 ); mesotibial length 2.85 mm (2.81–2.96; n=5); mesobasitarsal length 2.38 mm (2.22–2.52; n=5), maximum width 0.73 mm (0.67–0.74; n=5); metatibia triangular (right triangle) ( Fig. 142 ); metatibial anterior margin length 3.99 mm (3.93–4.04; n=5); metatibial ventral margin length 2.27 mm (2.15–2.37; n=5); metatibial postero-dorsal margin length 4.30 mm (4.22–4.44; n=5); metabasitarsal length 2.33 mm (2.22–2.37; n=5), proximal margin width 1.00 mm (0.96–1.04; n=5). Forewing length 10.48 mm (9.93–11.04; n=5); hind wing with 21–25 (n=5) hamuli. Maximum metasomal width 5.81 mm (5.70–5.93; n=5).

Coloration. Head with basal amber brown coloration and dominant golden-bronzy metallic color, especially on frons and paraocular areas; green metallic color accentuated on posterior area of vertex, around epistomal sulcus, on subgena, and contact area of compound eye and gena; malar area with large central yellow spot occupying more than two thirds of malar area length; mandible yellow on proximal half, margins and distal half brown ( Fig. 141 ). Mesosoma with dominant golden-bronzy coloration throughout, noticeable green coloration along margins and sulci/sutures, a few specimens with dominant green coloration and noticeable golden-bronzy iridescence (a contrasting condition when compared to most individuals) ( Figs. 139–140 ); legs mainly golden-bronzy to red with strong green iridescence, especially on distal podites of foreleg and outer surface of mesobasitarsus ( Figs. 140 , 142 ). Metasomal terga and sterna with strong bronzy-reddish coloration (a variable degree of green or dark-green intermixed), margins of all terga and sterna exhibiting golden and green iridescence ( Figs. 139–140 ).

Sculpturing. Head and mesosoma as described for E. bigibba , except mesoscutellum and mesoscutum with denser punctation ( Figs. 139–141 ). Metasomal terga and sterna (except smooth areas of first tergum and first sternum) densely punctate with small, shallow punctures [similar to sculpture found on species in decorata group, refer to Hinojosa-Díaz & Engel (2011a)] ( Figs. 139–140 ).

Vestiture. Head as described for E. bigibba (i.e., similar to E. mandibularis but lighter and with darker, sturdy setae on lower facial areas absent) ( Fig. 141 ). Mesosoma as described for E. bigibba , but light setae noticeably fulvous, becoming darker on dorsal areas (mesoscutum and mesoscutellum), and pale on ventral metasomal areas ( Figs. 139–140 ); specimens with darker integument have sturdier setae appearing light brown, in specimens with lighter integument such setae are concolorous with softer setae; mesoscutellar tuft, large, cordate (heart shaped, pointing anteriorly), slightly wider than long, occupying about one third of width and about three fourths of length of mesoscutellum, composed of dense, fulvous setae ( Fig. 139 ). Metasomal terga covered with moderately-dense, fulvous to light brown, simple, setae, those on anterior and lateral areas of first tergum as long as those on mesoscutellar margin, those on second to third terga slightly shorter than those on mesoscutum, those on fourth to seventh terga rather scattered and becoming light brown and long, second to sixth terga with noticeable, narrow, apical bands of pale, appressed setae ( Figs. 139–140 ); sterna with fulvous setae becoming pale and long alongside smooth, mid-sternal areas.

♂: Unknown.

HOLOTYPE: ♀, Brazil : “ HOLOTYPE; Euglossa ♀; perfulgens ; J.S. Moure 1964; Atas Simp. Biota; Amazonica; 5:388–391 [red label; name and year handwritten; publication data on underside] // Tefé; Amazonas BRASIL; Novembro 1959; R. Carvalho” ( DZUP).

ADDITIONAL MATERIAL EXAMINED (6♀♀): Peru : 1♀ (paratype), “ La Florida, Peru ; III-13-1931 // Paratype; Euglossa ; perfulgens ♀; J. S. Moure 1964 [type label, red]” ( AMNH) . 1♀, “PERU: Loreto; Iquitos ; X 1964; R. L. Dressler 133 [mixed handwritten] // Euglossa ; perfulgens Moure ; det. R. L. Dressler 1968” ( FSCA) . 1♀, as previous except identification label: “ Euglossa ; ( Euglossella ); perfulgens Moure ; Det. I. Hinojosa-Díaz 2012” ( SEMC) . 1♀, “Iquitos; Peru // 15Oct64; CH Dodson // on Ananas ; cosmos // Euglossa ; ( Euglossella ); perfulgens Moure ; Det. I. Hinojosa-Díaz 2012” ( FSCA) . 1♀, “Iquitos; Peru // 17Sep64; CH Dodson // Euglossa ; perfulgens Moure ; det. R. L. Dressler 1968” ( FSCA) . 1♀, “Iquitos; Peru // 17Sep64; CH Dodson // Euglossa ; perfulgens Moure ; det. R. L. Dressler 1968” ( FSCA) . 1♀, “Iquitos; Peru // 19-X-64; C.H. Dodson // Ananas ; comsos // E. ( Euglossella ); perfulgens ♀; Det. J. S. Moure 1993” ( DZUP) .

COMMENTS: When establishing the species, Moure (1967a) placed it within Euglossa s.str., and under the subgeneric concepts of the time (e.g., Moure, 1967b, 1970) predict- ed that the unknown male would have a bidentate mandible in accordance with his circumscription of Euglossa proper. As already discussed, Dressler (1978) redefined the subgenera, to which E. perfulgens clearly belonged within Euglossella as it was newly cast, and the unknown male would be accordingly be predicted to be tridentate. A feature of E. perfulgens that deserves mention is the presence of strong, hook-like setae on the anterior section of the galea ( Fig. 143 ). Similar setae are present in all females of Euglossa s.l., but never as long as those observed in E. perfulgens . It would be interesting to elucidate the use of such setae in E. perfulgens should biological observations at flowers ever become available.

Moure (1967a), in his original description of E. perfulgens , noted the differences in color between the two females he examined. The amount of intergrading golden-bronzy and green to dark-green coloration varies among individuals, such that some specimens have a rather greenish head and mesosoma, while others are more predominantly bronzy-red. The metasomal terga, because of the intergradation of those same colors, may be bronzy-red (i.e., more towards the red side of the spectrum) to dark purple, the latter seemingly resulting from greater intensity among the dark-green colors (very noticeable in the holotype). It is possible that the methods used to kill or preserve different specimens had some influence on these variations, but similarly dramatic (or even more so) color differences are known in E. decorata , which has a similar distribution ( Hinojosa-Díaz & Engel, 2011a). It must be stressed that despite the color variation observed, no structural differences exist among the specimens we examined and so they are otherwise a cohesive group.

The long malar area, rather protuberant clypeus, and long labiomaxillary complex ( Figs. 139–141, 143 ), make this species very close morphologically to E. bigibba . The large, characteristic “cordate” mesoscutellar tuft sits in a concavity very much like the one observed in E. bigibba as a result of the latter’s strongly biconvex mesoscutellum. The sizes of these two species are also comparable, as are the shape of the pronotal dorsolateral angle, the structure of the clypeus and labrum ( Figs. 135 , 141 ), and for the most part the vestiture. As mentioned previously in a different context, females almost invariably have a denser sculpturing than males, especially when looking at the metasomal terga, and this pattern tends to hold when comparing the male of E. bigibba to the female of E. perfulgens . Lastly, both taxa occupy similar ranges ( Fig. 170 ), albeit the locality data, like the available individuals themselves, are limited. When taken in their totality, these observations, combined with the reality that each species is known only from an opposing sex, makes a compelling case that they are instead conspecific ( E. bigibba thereby merely being the male of E. perfulgens ). While we have repeatedly avoided coloration as a primary trait separating species, it has always been done so in the context of colors that, for the very large part, are similar (e.g., varying degrees of green, or green versus blue, or mere differences in the intensity of particular highlights, &c.). Here, the colors are dramatically different (cf. Figs. 133–134 vs. 139–140) and not so easily reconciled as merely sexual dimorphism, particularly when males and females have not been captured together. We are aware that red individuals do occur within otherwise largely green species. For example, E. (Alloglossura) gorgonensis Cheesman is a noteworthy case of such color variation (e.g., Hinojosa-Díaz & Engel, 2012b; Hinojosa-Díaz & Brosi, 2013). In this species males and females are largely green in the southern portion of their range, while they become increasingly reddish to the north, seemingly forming a cline in color variation (even distinctive enough in range and color that the reddish form was described as a separate subspecies). The reddish color is more slight in the known females, but can be dramatic in males (e.g., Hinojosa-Díaz & Engel, 2012b). Even here, however, the more extensively red males still have strong green coloration intermixed throughout, particularly laterally whereby the ‘red’ stands out merely as intense golden-bronze among a lighter green and thereby retaining some of the intergradation between the two extremes. From the extremely limited material available, this is not the pattern observed between the color extremes represented by E. bigibba and E. perfulgens , nor do the colors cluster themselves in a distinctive cline of variation ( Fig. 170 ), as is observable in taxa such as E. gorgonensis . If the two were conspecific, then the pattern of color dimorphism, sexual or otherwise, would be unique within Euglossa . Thus, despite all of our great misgivings regarding the discreteness of E. bigibba and E. perfulgens , we momentarily retain them as separate species believing that this more conservative stance is the only one justifiable with so little material. We encourage the investment of collecting effort in those areas where both species are found (western Amazon Basin), and the application of molecular techniques to either better delimit these taxa or validate their conspecificity. Like E. bigibba , E. perfulgens is known from the central and western Amazon Basin in Brazil and Peru ( Fig. 170 ).

Figures

Figure 170. Collection localities for species of Euglossella Moure, viridis and mandibularis species groups [also showing localities for females attributable only to Euglossa (Euglossella) viridis (Perty)/azurea Ducke]. Locality points are based on examined specimens.

Figures 139–140. Euglossa (Euglossella) perfulgens Moure, female. 139. Dorsal habitus. 140. Lateral habitus.

Figures 141–143. Euglossa (Euglossella) perfulgens Moure, female. 141. Facial aspect. 142. Outer view of hind leg. 143. Anterior section of galea showing prominent hook-like setae.

Figures 135–138. Euglossa (Euglossella) bigibba Dressler, male. 135. Facial aspect of holotype. 136. Mesotibial tufts. 137. Proximal section of mesobasitarsus. 138. Outer view of metatibia and metatarsus.

Figures 133–134. Euglossa (Euglossella) bigibba Dressler, male holotype. 133. Dorsal habitus. 134. Lateral habitus.