Taxonomic notes and description of the male of ...

Zootaxa 3670 (3): 371–377 www.mapress.com / zootaxa / Copyright © 2013 Magnolia Press

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http://dx.doi.org/10.11646/zootaxa.3670.3.7 http://zoobank.org/urn:lsid:zoobank.org:pub:246ECD4B-CF76-4D95-AC2F-E8A5F0BC573E

Taxonomic notes and description of the male of Xenochlora nigrofemorata (Smith, 1879) (Hymenoptera: Apidae: Halictinae) LEANDRO M. SANTOS1,2 & GABRIEL A.R. MELO1,3 1

Laboratório de Biologia Comparada de Hymenoptera, Departamento de Zoologia, Universidade Federal do Paraná. Caixa Postal 19.020, 81531-980 Curitiba, PR, Brazil 2 Programa de Pós-graduação em Entomologia. E-mail: [email protected] 3 Corresponding author. E-mail: [email protected]

Abstract The present work describes for the first time the male of the bee genus Xenochlora Engel, Brooks & Yanega, 1997. The male of X. nigrofemorata (Smith, 1879) is described and illustrated. Additionally, Megalopta opacicollis Friese, 1926 is placed as a junior synonym of X. nigrofemorata (Smith, 1879). Key words: Augochlorini, Halictidae, Neotropical, taxonomy, systematics

Introduction Xenochlora Engel, Brooks & Yanega, 1997, a Neotropical bee genus in the tribe Augochlorini, contains four species, known from Guyana to Amazonas, in Brazil, and the Amazon basin in Peru and Ecuador (Michener 2007). Specimens of Xenochlora are rarely collected and before the study by Tierney et al. (2008) the genus was known from only six females, five of them type specimens (Engel et al. 1997). The nesting biology of the genus was studied recently by Tierney et al. (2008), based on four nests of X. nigrofemorata (Smith, 1879) and one of X. ianthina (Smith, 1861). Females of Xenochlora build their nests in dead wood, mostly small dead branches suspended in the understory vegetation, and exhibit nest sharing behavior, with conspicuous variation in body size among nestmate females (Smith 1861; Tierney et al. 2008). When originally proposed by Engel et al. (1997), Xenochlora was considered most closely related to Megalopta, a position supported by the phylogenetic study of Engel (2000), in which Xenochlora was placed as sister group of Megalopta. This same relationship has also been retrieved in some of the analysis from a more recent study by Tierney et al. (2012), when using data from the gene coding for the long-wavelength green opsin. However, in the analysis combining the three genes sampled, Megalopta came out paraphyletic, with Megalopta atra Engel, 2006 forming a basal group together with Xenochlora. This latter arrangement has prompted Tierney et al. (2012) to place Xenochlora as a subgenus of Megalopta. Michener (2000, 2007) has also considered placing Xenochlora within Megalopta, but refrained from changing its status arguing that the position of Xenochlora could not be determined unequivocally, since its males were then unknown. In this way, we describe here for the first time the male of a species of Xenochlora, based in a specimen of X. nigrofemorata from Rio Branco, in Acre, Brazil, showing that it differs in many aspects from males of Megalopta. We also provide new distribution records for X. nigrofemorata and notes on Megalopta opacicollis Friese, 1926, placing it as a junior synonym of X. nigrofemorata.

Material and methods Listed museums and their respective acronyms are as follows: Coleção Entomológica Padre Jesus Santiago Moure,

Accepted by C. Rasmussen: 27 May 2013; published: 13 Jun. 2013

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Departamento de Zoologia, Universidade Federal do Paraná, Curitiba, Brazil (DZUP), Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil (INPA), Natural History Museum, London, England (BMNH) and Museum für Naturkunde, Berlin, Germany (ZMB). The terminology for the external morphology follows Eickwort (1969), Engel (2000) and Michener (2000, 2007), except for the the scutum, referred as mesoscutum, and the “basal area of propodeum”, here the metapostnotum, following Brothers (1976); the terminology for the male terminalia follows that of Eickwort (1969). The following abbreviations are used: F1–F11 for the flagellomeres; T1–T6, metasomal terga; and S1–S8, metasomal sterna. The punctation density is described in relation to the interspaces between punctures, measured in terms of puncture diameter (pd). The information provided between quotation marks in the Additional examined material section is an exact transcription of the labels associated with the specimens. The quotation marks indicate the different labels in the same specimen, the inverted bars (\) indicate different lines in the same label.

Taxonomy Xenochlora Engel, Brooks & Yanega, 1997 Xenochlora Engel, Brooks & Yanega, 1997: 7. Type species Xenochlora ochrosterna Engel, Brooks & Yanega, 1997.

Comments. According to Engel (2000) and Michener (2000, 2007), Xenochlora differs from Megalopta in the non enlarged ocelli, hamuli in series broken by gaps (as in most other Augochlorini), some hooks thus isolated, and hind tibia and basitarsus largely covered with black setae. Adittionaly Xenochlora differs from Megalopta by: male S3 with digitiform apical lobes (Fig. 13); S4 lacking stiff setae along mid longitudinal sulcus (Fig. 14); apical margin of S5 with broad mid emargination and sinuous lateroapical margin (Fig.15); ventral parapenial lobe narrow along most of its length, its apex only weakly expanded (Fig. 17).

Xenochlora nigrofemorata (Smith, 1879) (Figs. 1–19) Megalopta nigro-femorata Smith, 1879: 48. Holotype female, Brazil: Amazonas, Tefé (‘Ega’) (BMNH, not examined). Megalopta opacicollis Friese, 1926: 121, 131. Holotype female, Brazil: Amazonas, Santo Antonio do Içá (ZMB, examined). New synonymy.

Comments. The male specimen described here is partly damaged, missing F2-F11 in right antenna and F3-F11 in left antenna, left foreleg apical to coxa, and apical tarsomeres in most legs (Figs. 7–8). The new synonymy established here, placing M. opacicollis under X. nigrofemorata, was based on the species concepts presented by Engel et al. (1997). It should be considered tentative, especially because the study of Engel et al. relied mainly on differences of color pattern between the different forms they recognized as species. Description of male. Head. Mostly metallic greenish bronze, except for pale yellow mandible, labrum and apex of clypeus. Labrum with low, weakly-bilobed basal elevation. Disc of clypeus with its central portion protuberant subapically, punctation sparse and mostly coarse, pilosity composed of long, simple setae and a few shorter finely plumose hairs laterally. Epistomal sulcus acutely angled laterally, forming a short paraocular lobe into clypeus. Basal one-third of supraclypeal area with dense punctation and plumose pilosity, apical two-thirds mostly smooth, with only a few punctures. Parocular area and frons with dense decumbent pilosity, punctures on lower parocular area mostly fine, on upper parocular area and frons coarse and mostly contiguous. Scape reddish brown, gradually widening apically, F1 about two-thirds as long as F2. Vertex with punctation similar to that of frons (Fig. 9). Gena with coarser and denser punctation on upper portion, punctation becoming sparser and finer laterally; lower portion mostly glabrous, longest setae on lower gena about as long as those on clypeus. Eyes not greatly enlarged, maximum eye width (in frontal view) about 0.5x upper interorbital distance, furrow surrounding ocelli present, ocellocular distance a little more than one ocellar diameter. Mesosoma. Mostly metallic greenish bronze, except for reddish brown to brown tegula and wing veins, coxae, trochanters, mid and hindtibiae brown, femora and foretibiae mostly reddish brown with some brown areas, tarsi mostly pale reddish brown. Pronotum

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FIGURES 1–6. Xenochlora nigrofemorata, female holotype of Megalopta opacicollis Friese, 1926. 1. Head, frontal view. 2. Mesosoma, dorsal view. 3. Mid and hind legs, in lateral view. 4. Mesosoma, posterodorsal view. 5. Metasoma, dorsal view. 6. Specimen labels.

with lateral angle upturned dorsally, forming an almost right angle, lateral carina present, relatively low. Anterior one-fifth and lateral portions of mesoscutum, adjacent to parapsidial line, with coarse and mostly contiguous punctation, puncture diameter similar to those on vertex (Fig. 10); punctation becoming gradually sparser toward central and posterior portions of disc; dense short plumose pilosity, with sparser intermingled long setae, covering most of mesoscutum, except for its central portion (Fig. 10). Scutelum and metanotum with relatively fine and sparse punctation; pilosity similar in size and shape to that of scutellum (Fig. 11). Basal area of metapostnotum about 0.8x as long as metanotum; longitudinal rugulosities present along its entire extension; surface between rugulosities smooth (Fig. 11). Lateral and posterior surfaces of propodeum with dense punctation (about 1 pd). Lateral portion of mesepisternum and metepisternum with punctation and pilosity similar to that of scutellum; subalar area and most of ventral portion with sparser punctation; metepisternal process absent. Hind wing with ten irregularly spaced hamulli. Metasoma. T1 mostly brown with conspicuous purple tints, central portion of dorsal surface and ventro-lateral areas reddish brown. Disc of T2 mostly reddish brown, except for sublateral portion brown with purple tints, lateral and ventro-lateral areas light reddish brown. Disc of T3 and entire T4-T7 brown with purple tints, ventro-lateral areas of T3 light reddish brown. T1-T3 with coarse, relatively dense punctation, punctures smaller on marginal zone of T3; pilosity simple, mostly short and dense (Fig. 12). T4-T7 with much sparser and shallower punctation, except for marginal zone of T4; lateral areas of T4-T6 and entire T7 with conspicuously long simple setae with curved apex; setae on T7 about as long as length of sclerite. Sterna mostly reddish brown. S1 and S2 with sparse punctation, the surface between punctures finely and weakly TAXONOMIC NOTES ON XENOCHLORA

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microreticulated. S3 with a shallow longitudinal sulcus along its midline, apical lobes long and digitiform, covered with stiff and short setae (Fig. 13). S4 with a basal protruding process; longitudinal sulcus and lateral process present; patch of stiff setae restricted to apical margin (Fig.14). S5, S6, and genitalia as in Figs. 15–18. Measurements (in mm). Approximated body length: 8.0; maximum head width: 2.9; intertegular distance: 3.1; forewing length, including tegula: 7.4.

FIGURES 7–12. Xenochlora nigrofemorata, male from Rio Branco, Acre, Brazil. 7. Habitus, dorsal view. 8. Habitus, lateral view. 9. Head, dorsal view. 10. Mesoscutum, dorsal view. 11. Detail of mesosoma, posterodorsal view. 12. Detail of terga 1 and 2, dorsal view.


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FIGURES 13–18. Xenochlora nigrofemorata, male from Rio Branco, Acre, Brazil. 13. Sternum 3, ventral view. 14. Sternum 4, ventral view. 15. Sternum 5, ventral view. 16. Sternum 6, ventral view. 17. Genitalia, ventral view. 18. Genitalia, dorsal view.

Type material examined. The type material of Megalopta opacicollis was found filed in the ZMB card catalog under the manuscript name “Megalopta opaciceps”, since the specimen has been labelled as such by Friese (Fig. 6). However, judging from the data of the collecting label (Fig. 6) and the close agreement with the original TAXONOMIC NOTES ON XENOCHLORA


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description, there is no doubt that this specimen is the true holotype and that the name was changed to M. opacicollis in Friese’s (1926) revision. The specimen is partly broken, with the head, right forewing and one antenna glued to a paper triangle (Figs. 1–2). Also, it lacks the right hindwing and one antenna. While Friese (1926) did not explicitly indicate that he had only a single specimen available when describing this species, the extreme rarity of Xenochlora specimens and the fact that Friese did not indicate, on the other hand, that he had multiple specimens, suggest this is a holotype rather than a syntype. The specimen has now been labeled as the holotype of M. opacicollis. Additional examined material. Brazil. Acre: 1♂ (DZUP), “Faz. Catuaba – UFAC\ armadilha luminosa\ capoeira” “2859” “08248” [Brazil, Acre, Rio Branco, 67º37'W, 10º04'S]. Amazonas: 1♀ (INPA), “BRA, AM, Manaus\ PDBFF – Colosso\ 02° 23’ 58”S –59°52’30”W”\ 18–20.v.2010\ D. Storck-Tonon Leg.”. Maranhão: 1♀ (DZUP), “Buritucupu-MA\ Brasil 27/VII/96\ Pereira & Pinto\ 2145” “Horário: 7–8\ Nº PL: 35 *” “46” “Xenochlora\ nigrofemorata\ det. GAR Melo 2004”. Rondônia: 1♀ (DZUP), “Brasil, RO, Porto Velho\ Rio Madeira, Área Mutum\ -9.59 S -65.05 W\ 17-30.VI.2011\ N.V.Sydney & L. Cezar”; 1♀ (DZUP), same data, except “Área Caiçara\ -9.42 S -64.82 W”.

FIGURE 19. Distribution records for Xenochlora nigrofemorata. Squares: literature records; circles: new distribution records.


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Distribution. Brazil (Acre, Amazonas, Maranhão, Rondônia); Guyana (Georgetown); Peru (Madre de Díos) (Fig. 19).

Acknowledgments We are grateful to Rui Peruquetti and Patricia Drumond for donation of the male of X. nigrofemorata, Rodrigo B. Gonçalves for donating the females from Rondônia to DZUP, to Marcio L. de Oliveira and Danielle S. Tonon for the loan from INPA, and to Claus Rasmussen for suggestions to the manuscript. GARM thanks Frank Koch and Michael Ohl for their kind assistance during visit to the ZMB. Partial support has been provided by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) to LMS (140949/2010-0) and to GARM (303858/ 2009-5, 453268/2010-2).

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