Xylocopa dimidiata Latreille 1809
Creators: name: Villamizar, Germán
name: Fernández, Fernando
name: Vivallo, Felipe
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Apidae
Xylocopa
Xylocopa dimidiata

description: Xylocopa dimidiata Latreille, 1809
(Figures 15–18, 77)
Xylocopa dimidiata Latreille, 1809: 95
Xylocopa batesi Cockerell, 1907: 228. (nomem invalidum according to Lucia & Gonzalez, 2017).
Diagnosis. The females can be identified by the following combination of characters: large body size (body length~ 22.5 mm); integument black with bluish/violaceous highlights on head and legs and slightly bluish and greenish on mesosoma and metasoma; base of labrum with distinct, large, single capitate tubercle approximately as large as median ocellus; pubescence mostly black; wings dark brown with greenish iridescence apically and violaceous basally; short simple hairs barely noticeable on metasomal discs, T2 and T3 glabrous. X. dimidiata is very similar to X. simillima by the body size, labrum shape and punctation on metasoma, but both differ in the coloration of the integument and pubescence, the disposition of the highlights and the iridescence on wings. X. simillima has the integument dark brown to black with reddish brown areas on T1–T4, pubescence mostly ferruginous to black, slightly bluish highlights only on mesosoma and wings with blue and violet iridescence, while X. dimidiata has the integument and pubescence black, weak bluish and greenish highlights on most of body and wings with green iridescence apically and violet basally.
Morphology. Female (Figs. 15–18). Measurements (mm): Approximate body length: 22.5; head width: 7.3; mesosoma width: 8.6; metasoma width: 10; forewing length: 18. Coloration: Integument black with weak bluish and greenish highlights on mesosoma and metasoma, and slightly bluish/violaceous highlights on head and tibiae. Tegula dark brown with greenish highlights. Wings dark brown with greenish iridescence apically and bluish/violaceous basally. Pubescence: Black except ferruginous on labrum, ventral surface of fore basitarsus basally and apex of T6. Sparse and short plumose hairs on vertex (0.3–0.5x OD), glabrous on upper gena; face with dense plumose and simple hairs inter-mixed (0.5–1.5x OD), simple hairs longer on lower gena. Mesosoma covered by dense and short plumose hairs (0.5–1x OD) mainly on mesepisternum and ventrally; sparse and short plumose hairs (0.3–1x OD) on posterior margin of mesoscutellum and smooth on disc of mesoscutum and anterior area of mesoscutellum. Long, decumbent, simple hairs grouped in tufts on lateral sides of metasoma; sparse and short simple hairs (0.1–0.3x OD) on disc of T1, longer and denser on lateral sides and anteriorly; discs of T2 and T3 glabrous; discs of T4 and T5 with regular, semi erected and short simple hairs (0.2–0.5x OD), longer and denser on T5; sterna with long simple hairs mostly on posterior area. Surface sculpture: Circular, fine and sparse punctures on vertex (2–4x puncture width) with impunctate areas near ocellus and toward upper gena; paraocular area and lower half of clypeus with circular to elliptical, coarse and dense punctures (0.5–1x puncture width). Fine and sparse punctation on mesoscutum (2–5x puncture width), denser near tegula; mesonotal line inconspicuous with similar length to half of mesoscutum, parapsidal lines poorly defined; mesoscutellum with fine, scattered, circular punctures on most of disc, denser posteriorly. Fine and dense punctation (0.5–2x puncture width) on T1 disc, denser on anterior margin and lateral sides; discs of T2–T4 with circular to elliptical, coarse and scattered punctures (2–5x puncture width), sparser medially and denser on lateral sides; disc of T5 strongly imbricate and smooth on medial distal margin; circular to elliptical, fine and scattered punctures on sterna, denser and coarser mainly on last segments. Structures: Head broader than long (1.2: 1); inner orbits of compound eyes relatively parallel; ratio of upper and lower interocular distances 0.8:1; maximum interocular distance equal than eye length (1: 1); clypeus broader than long (2.1: 1) with the length equal to clypeocellar distance (1: 1); interalveolar distance less than alveolocular distance (0.6: 1); interalveolar distance less than alveolocellar distance (0.8: 1); vertex broad, lateral ocellus below supraorbital line (0.8x OD); interocellar distance shorter than ocellocular distance (0.7: 1). Frontal carina at the same level of antennal sockets, with similar size than scape length (0.3x OD). Length of F1 longer than the summed length of F2 and F3 and shorter than length of F2–F4 (0.8: 0.8: 0.9). Base of labrum with a distinct, large, single capitate tubercle, approximately as large as median ocellus. Mesoscutellum rounded (lateral view). Metanotum and propodeum subvertical (lateral view).
Floral records. Unknown.
Type Material. Neotype female designated by Lucia & Gonzalez (2017) (NHMUK, examined).
Type locality. BRAZIL: Amazonas: Tefé.
Distribution in Colombia (Fig. 77). Amazonas: Probably in La Pedrera, according to Dugand (1948).
Material examined (n = 1♀). COLOMBIA: Amazonas: 1 female: Colombia, amazonica, R. Caquetá, XI – ‘12. Ducke (MPEG).
Comments. We found a single specimen of Xylocopa dimidiata from Colombia collected by the botanist Adolpho Ducke in his travel thought the Amazonas in 1912–1919 (Dugand, 1948). That specimen was compared with the neotype designated by Lucia & Gonzalez (2017) and some Brazilian exemplars housed at INPA and MPEG. All these specimens were recorded in the Amazonian region (Boreal Brazilian dominion sensu Morrone, 2014) and have integument and pubescence predominantly black, bluish/violaceous tone on head and fore tibia, discs of T2 and T3 nearly glabrous, and slightly bluish and greenish highlights on mesosoma and metasoma. We only noticed a small variation in darker specimens that were collected in the same locality, which do not show highlights on mesosoma and metasoma, and the basal iridescence of the wings is bluish instead of violaceous. However, it is not clear if this variation is related to the state of preservation of the specimens or if actually is a geographic variation of this species.
Furthermore, we noted the difficulty to differentiate X. simillima from X. dimidiata when studied material from foreign collections. Despite having examined the type material of both species, the features to separate them are very superficial and in some cases variables. Both species have similar sculpture and disposition of the pubescence, but differ mainly in the coloration and highlights of the integument. Moreover, it is interesting the distribution of both species because X. dimidiata occurs mainly in the Amazon basin while X. simillima occurs from Colombia to Argentina. The male is still unknown.
description: Published as part of Villamizar, Germán, Fernández, Fernando & Vivallo, Felipe, 2020, Synopsis of the carpenter bee subgenus Xylocopa (Schonnherria) Lepeletier, 1841 (Hymenoptera: Apidae) in Colombia, with designation of lectotypes and the description of two new species, pp. 301-347 in Zootaxa 4789 (2) on pages 308-309, DOI: 10.11646/zootaxa.4789.2.1, http://zenodo.org/record/3887576