Xylocopa bambusae Schrottky, 1902

Lucia, Mariano, Gonzalez, Victor H. & Abrahamovich, Alberto H., 2015, Systematics and biology of XylocopasubgenusSchonnherria (Hymenoptera, Apidae) in Argentina, ZooKeys 543, pp. 129-167 : 132-135

Taxon classification Animalia Hymenoptera Apidae

Xylocopa bambusae Schrottky, 1902 Figures 1, 7, 13, 19, 25, 30, 35, 40, 57

Xylocopa bambusae Schrottky, 1902: 475 (holotype: MZUSP; ♂, Rio Grande do Sul, Brazil) (examined)

Xylocopa eburnea Friese, 1903: 202 (lectotype: ZMB; ♂, Rio Grande do Sul, Brazil); Hurd and Moure 1961: 186 (lectotype designation and synonym with bambusae )

Xylocopa bellula Brèthes, 1916: 413 (holotype: MACN; ♀, Misiones, Argentina (examined); Hurd and Moure 1961: 187 (synonym with bambusae and unneccesary lectotype designation)

Xylocopa (Xylocospila) bambusae : Hurd and Moure 1963: 109.

Diagnosis.

The female of this species can be easily distinguished from other Argentinean species of Schonnherria by the following combination of characters: small body size (body length 14-17 mm); integument dark brown to black throughout, without metallic highlights; clypeus flat in profile, not elevated from adjacent paraocular area; clypeoalveollar distance long, about twice as long as longitudinal diameter of antennal socket; frontal carina projected into a distinct tubercle just above or at the upper tangent of anntenal sockets (Fig. 1); vertex and metasomal terga with large impunctate areas (Fig. 13); wings dark brown with weak coppery highlights basally, violet distally. The male can be easily recognized by the following combination of characters: small body size as in the female; body pubescence long, dense (obscuring integument in most areas), yellowish to reddish brown; supraclypeal area with a distinct tuft of long, erect, dense setae obscuring integument (Fig. 7); T1-T5 dark reddish brown, each with a distinct, broad, median yellow maculation on disc, sides and distal margins (inmaculate areas) densely covered by long, dense dark brown setae (Fig. 19). The female of this species superficially resembles Xylocopa splendidula and other small species of Schonnherria such as Xylocopa lucida Smith and Xylocopa muscaria (Fabricius) (not occurring in Argentina); however, those species have distinct metallic blue highlights on the body as well as different patterns in the punctation, pubescence, and wing coloration. The supraclypeal tuft of setae and pale maculations on the metasomal terga of the male of Xylocopa bambusae are so distinctive and unique among species of Schonnherria that these characters have been used to justify its recognition in a different subgenus.

Female.

Body length 15.9 (14.0-17.3); head length 4.2 (3.9-4.4); head width 4.9 (4.6-5.0); mesosoma width 5.7 (5.2-6.0); metasoma width 6.5 (5.8-6.8); forewing length 13.2 (12.3-13.7); forewing width 3.8 (3.6-4.0). Coloration. Integument dark reddish brown to black throughout, without metallic highlights, light brown on anterior face of F2-F9 and impunctate distal margins of metasomal terga and sterna. Wings dark brown with coppery highlights basally, golden iridescent. Pubescence. Dark brown to black. Head with scattered setae on vertex, gena, and clypeus distally (Fig. 1). Mesosoma with abundant, plumose setae except nearly asetose on discs of mesoscutum and mesoscutellum. T1 with scattered plumose setae on basal half, scattered, very short simple setae on distal half; T2-T4 medially with very short, simple setae, each seta barely exiting puncture; T3-T6 with long setae laterally; T5 with short (~1.0 × OD), simple setae on disc; T6 with dense, long, both simple and plumose setae (Fig. 13); sterna with longer, denser, semierect setae than on terga. Sculpturing. Weakly imbricate to smooth and shiny. Vertex and upper gena largely impunctate, punctures small and scattered. Mesoscutum with scattered, coarse punctures on anterior margin and lateral to parapsidal lines, impunctate otherwise; mesoscutellum largely impunctate, with large, scattered punctures on disc. Metasomal terga with circular to ovoid punctures as large and coarse as those on mesoscutellum, most punctures separated by at least two times a puncture width, punctures denser laterally and on T5; sterna with elongate punctures on discs, punctures contiguous laterally, becoming sparser medially. Structure. Head broader than long (1.1-1.2:1); compound eyes with inner margins parallel; proportion of upper to lower interocular distance 1:1; middle interocular distance 2.9-3.0; vertex broad, distance between median ocellus and posterior margin of vertex 3.2-4.3 OD; orbitoccipital distance 0.75-0.85; lateral ocelli on supraorbital line; interocellar distance to ocelocular distance 1.0-1.3:1; interocellar to ocelloccipital 0.7-0.9:1; ocellocular to alveolocellar 0.6-0.7:1; orbitoccipital to ocellocular 1.1-1.3:1; alveolocular to interalveolar 0.9-1.1:1; clypeoalveolar distance long, about twice as long as longitudinal diameter of antennal socket; clypeocellar distance to distance between median ocellus and posterior margin of vertex 1.2-1.3:1; frontal carina projected into a distinct tubercle just above or at the upper tangent of anntenal sockets; clypeus broader than long, 2.0-2.4:1; proportion of length of scape, pedicel and F1-F4: 2.5 –2.9:0.3–0.4:1:0.3–0.4:0.3– 0.4:0.4, respectively; labrum broader than long, with three basal tubercles, median tubercle distinct, longitudinally enlongate, sublateral tubercles small, obscured by pubescence. Mesoscutellum gently convex; metanotum and propodeum obliquely inclined.

Male.

As in the female, except for usual secondary sexual characters and as follows: body length 15.9 (15.0-16.7); head length 3.5 (3.5-3.6); head width 4.4 (4.4-4.6); mesosoma width 6.3 (6.0-6.6); metasoma width 6.6 (6.0-7.0); forewing length 11.6 (11.0-12.7); forewing width 3.6 (3.4-3.8). Coloration. Cream to yellowish maculations as follows: labrum, mandible basally, clypeus, supraclypeal area, paraocular area (except on upper one-third), anterior surface of flagellum (Fig. 7), outer surface of profemur basally, outer surfaces of protarsi, and discs of T1-T6 (maculations narrower on apical terga, sometimes absent on T4-T6) (Fig. 19). Wings subhyaline, yellowish with faint coppery highlights. Pubescence. Longer, denser than on female, yellowish to reddish brown, darker on face, vertex, sides of mesoscutum, mesoscutellum, metanotum, and inmaculate areas of terga (Fig. 19); supraclypeal area with a distinct tuft of long, erect, dense setae obscuring integument (Fig. 7); discs of mesoscutum and mesoscutellum asetose; maculated areas of terga with scattered erect setae. Sculpturing. Vertex and gena more densely punctate than in female, punctures separated by 1-2 times a puncture width; tegula impunctate, smooth and shiny on disc, otherwise dull, punctate (1-2 times a puncture width). Metasomal terga densely punctate (a puncture width or less) on inmaculated areas, including distal margins; punctures scattered on maculated areas. Structure. Middle interocular distance 2.0-2.1; distance between median ocellus and posterior margin of vertex 2.2-2.9 OD; orbitoccipital distance 0.4-0.6; interocellar to ocelocular distance 2.3-3:1; interocellar to ocelloccipital 1.2-1.4:1; ocellocular to alveolocellar 0.2-0.4:1; orbitoccipital to ocellocular 1.7-2.2:1; alveolocular to interalveolar 0.8-0.9:1; clypeoalveolar distance 1.5 × longitudinal diameter of antennal socket; clypeocellar distance to distance between median ocellus and posterior margin of head 1.3-1.6:1; frontal carina strongly elevated, short 0.7-0.8, not tuberculiform as in female; clypeus broader than long, 1.5-1.6:1; proportion of length of scape, pedicel and F1-F4: 2.5 –2.7:0.3– 0.4:1:0.4:0.4:0.4. Mesoscutellum nearly flat, exposed, along same inclined plane with metanotum and base of propodeum; protrochanter with distinc spine; ventral surface of metatrochanter and metafemur basally glabrous, distinctly protuberant. Genitalia as in Figs 25, 30, 35, 40.

Distribution.

This species is also known from Brazil and Paraguay (Table 1). In Argentina it has only been recorded from the province of Misiones, which is included in the Paranaense biogeographic province (Fig. 57).

Comments.

Hurd and Moure (1961: 186-187) designated a male and a female syntype as the lectotype of Xylocopa eburnea and Xylocopa bellula , respectively. In both cases Hurd and Moure (1961) unambiguously selected a specimen, provided information on the label data and repository collection, and clearly designated it as the sole name-bearing specimen, thus complying with the ICZN, Article 74. Such lectotypes designations appear to have been missed by Moure (2007: 673) who indicated syntypes for both species. The lectotype designation is valid for Xylocopa eburnea because Friese clearly mentions the existence of several males and females in the original description. However, the lectotype designation is unnecessary for Xylocopa bellula because Bréthes indicated a single female in the original description, which is currently housed at MACN. This specimen has a locality label that reads "Misiones, XII-1911, Abel Muniez", a label in Bréthes’ handwriting and a holotype label [probably added recently]. Two other females, each bearing a locality label that reads “Misiones”, are also found with that specimen; one of them bears a lectotype label. Perhaps because of the additional two specimens, Moure and Hurd (1961) thought of them as syntypes and designated as lectotype the female collected on 1911. Curiously, the lectotype label is not found in that specimen but in one of the two additional females. To avoid further confusion, we added a red label with the following note to the type: 'This is the true type as indicated in Bréthes’ (1913) original description. M. Lucia & V.H. Gonzalez 2015'.

Despite actively searching for nests as well as specimens of this species in insect collections and in the field, the only specimens available to us were those collected by Peter Jörgensen at different times of the year in Misiones during the first decade of 1900 (see supplemental material). The species has not been collected ever since. The nesting biology of this Xylocopa bambusae is unknown, although it presumably nests in bamboo stalks ( Schrottky 1902).