Triepeolus buchwaldi ( Friese, 1908 )

Onuferko, Thomas M., Rightmyer, Molly G., Melo, Gabriel A. R. & Roig-Alsina, Arturo, 2024, A revision of the South American species of the cleptoparasitic bee genus Triepeolus Robertson, 1901 (Hymenoptera: Apidae), European Journal of Taxonomy 931, pp. 1-50 : 14-18

Triepeolus buchwaldi ( Friese, 1908)

Figs 1C , 4C , 6

Epeolus buchwaldi Friese, 1908: 87 (♀, ♂), lectotype presently designated.

Triepeolus megadelphus Cockerell, 1914: 314 (♂), syn. nov.

Triepeolus aguilari Moure, 1955: 130 (♂), syn. nov.

Triepeolus buchwaldi – Cockerell 1913: 372.

Non? Epeolus xanthurus Cockerell, 1917 – Moure & Melo 2007: 590 (incorrectly tentatively synonymized with T. buchwaldi ).

Diagnosis

The following morphological features in combination tell T. buchwaldi apart from all other South American Triepeolus : the mesoscutum does not have long (≥ ½ MOD), erect setae ( Fig. 4C ); the T1 basal band is arched and continuous with (and indistinguishable from) the lateral longitudinal bands, such that the discal patch is semicircular or triangular ( Fig. 6B ); T1–T4 have medially interrupted bands of pale-yellow tomentum ( Fig. 6B ); and the T2 apical transverse bands have lobe-like anterolateral extensions ( Fig. 6A–C ). Triepeolus buchwaldi is very similar in overall appearance to T. atoconganus and T. cecilyae , but in the latter two species the dorsum of the mesosoma (at least anterolaterally) and mesopleura (at least in the upper half) have dense, long (≥ ½ MOD), erect/suberect, minutely branched setae.

Etymology

The specific epithet (declined in the genitive case) honors G.V. Buchwald, who collected the lectotype ( Friese 1908).

Material examined

Primary type material

ECUADOR • ♂, lectotype of E. buchwaldi ; Guayas, Guayaquil ; 1901; G.V. Buchwald leg.; ZMB 8e2500 • ♂, holotype of T. megadelphus ; Guayas, Guayaquil ; May–Jun. 1913; C.T. Brues leg.; AMNH AMNH _ IZC 00323951 .

PERU • ♂, holotype of T. aguilari ; Lima, Lima ; Jan. 1949; P. Aguilar leg.; DZUP .

Secondary type material

ECUADOR • 1 ♀, paralectotype of E. buchwaldi ; Guayas, Guayaquil ; Apr. 1901; Buchwald leg.; AMNH No. 25147 • 2 ♀♀, paralectotypes of E. buchwaldi ; same collection data as for preceding; Apr. 1901; Buchwald leg.; ZMB .

Non-type material

ECUADOR • 1 ♂; El Oro, 19 km NE of Piñas ( Hotel Machay ); 2 Jul. 1989; L. Stange and R. Miller leg.; FSCA M.G.R. Database No. 3490 • 1 ♀; same collection data as for preceding; 5 Jul. 1989; L. Stange and R. Miller leg.; FSCA M.G.R. Database No. 1327 • 1 ♂; Guayas, Guayaquil ; 1930; F. Campos leg.; DZUP • 1 ♀; Guayas, Playas ; 26 Feb. 1972; M. Deyrup leg.; AMNH • 3 ♀♀; same collection data as for preceding; 3 Apr. 1987; M. Cooper leg.; NHMUK NHMUK013620574 , NHMUK013620578 , NHMUK013620585 • 1 ♂; Loja, Loja ( 14 km W of Catamayo ); 9 Jul. 1989; L. Stange and R. Miller leg.; FSCA M.G.R. Database No. 3491 • 1 ♀; Manabí, Canoa ; 10 Jan. 1981; A. Roig leg.; MACN • 2 ♂♂; Manabí, Chone ; May 1976; M. Fritz leg.; MACN • 1 ♀; Manabí, Portoviejo; 30 Apr. 1969; P. Alcivar leg.; USNM M.G.R. Database No. 5936 • 16 ♀♀; same collection data as for preceding; 30 Apr. 1969; P. Alcivar leg.; USNM • 1 ♂; Santa Elena, El Azúcar (near Santa Elena); 12 Apr. 1977; M.E. Irwin leg.; INHS 387483 .

PERU • 1 ♀; Áncash, 1 km NE of Carhuaz ; 15 May 1996; J.G. Rozen and A. Ugarte leg.; AMNH M.G.R. Database No. 2264 • 6 ♀♀; Cajamarca, 14 km E of Tembladera ; 7.2017° S, 79.0386° W; 22 Mar. 1999; J.G. Rozen and A. Ugarte leg.; AMNH M.G.R. Database Nos. 2245 , 2247 , 2255 , 2257 , 2261 , 2263 • 1 ♀; same collection data as for preceding; 22 Mar. 1999; J.G. Rozen and A. Ugarte leg.; AMNH AMNH _ IZC 00292365 /M.G.R. Database No. 2260 • 14 ♀♀; same collection data as for preceding; 24 Mar. 1999; J.G. Rozen and A. Ugarte leg.; AMNH M.G.R. Database Nos. 2246 , 2248 , 2249 , 2250 , 2251 , 2252 , 2253 , 2254 , 2256 , 2258 , 2259 , 2262 , 3707 , 3708 • 1 ♂; La Libertad, Cartavio ; 20 Mar. 1987; E.G. Sayth leg.; LACM M.G.R. Database No. 3653 • 1 ♂; La Libertad, Chillia; 15 Mar. 1953; Weyrauch leg.; IFML • 1 ♀, 6 ♂♂; La Libertad, Simbal; 4 Jul. 1974; L. Stange and C. Porter leg.; IFML • 1 ♀; Lambayeque, 32 km ENE of Olmos; 21 May 1996; J.G. Rozen and A. Ugarte leg.; AMNH M.G.R. Database No. 1328 • 1 ♀; Lambayeque, Lambayeque ; 5 Mar. 1981; M.E. Irwin leg.; INHS 7774 /M.G.R. Database No. 3706 • 1 ♀, 1 ♂; Lima, Chosica; 20 Feb. 1928; R.C. Shanon leg.; USNM • 1 ♂; same collection data as for preceding; 7 Apr. 1970; R. García leg.; DZUP • 1 ♀; Lima, Lima ; 3 Feb. 1949; P. Aguilar leg.; UNMSM • 1 ♂ (erroneously labeled as the holotype but actually a non-type specimen); same collection data as for preceding; 3 Feb. 1949; P. Aguilar leg.; UNMSM M.G.R. Database No. 3488 • 1 ♂; Lima, Miraflores (Lima); 3 Feb. 1949; P.A.F. leg.; IFML FC 234 • 1 ♂; Lima, Río Chillón ; 14 Mar. 1953; Weyrauch leg.; IFML • 1 ♂; Lima, Río Lurín ; 22 Nov. 1952; Weyrauch leg.; IFML • 1 ♂; Lima, Valle del Chillón ; 6 Mar. 1966; R. García leg.; UNMSM M.G.R. Database No. 3489 • 1 ♂; Piura, Querecotillo; 23 Jul. 1982; R.B. Miller and L. Stange leg.; FSCA .

Non-preserved material

PERU • 1 ♀; Lambayeque, Lambayeque ; 31 Jan. 2023; M. Campos obs.; iNaturalist record #152688525 .

Redescription

MEASUREMENTS OF LECTOTYPE. Body length 8.8 mm; ITW 1.7 mm; head length 2.0 mm; head width 2.8 mm; fore wing length 7.3 mm.

Both sexes

INTEGUMENT COLORATION. Dark brown to black except as follows. Mandible with apical third golden yellow (entirely dark brown/black in some non-type specimens). Mandible with basal two-thirds, scape and pedicel to some extent, F1 extensively, pronotal lobe, tegula, coxae to some extent, trochanters to tarsi (excluding brown meso- and metatibial spurs) partially to entirely, metasomal terga laterally, and metasomal sterna to some extent orange. Fore wing membrane subhyaline, apically dusky. Hind wing membrane dusky subhyaline to hyaline. Pygidial plate to some extent reddish brown.

PUBESCENCE. Face with tomentum densest around antennal socket. Tomentum slightly sparser on clypeus; upper paraocular and frontal areas and vertexal area mostly exposed. Pronotal collar with tomentum uniformly pale yellow. Mesoscutum with well-defined paramedian band of pale-yellow tomentum, tapering slightly toward and attaining anterior margin; pale tomentum otherwise mostly restricted to lateral and posterior margins. Mesopleuron with off-white, appressed, branched setae; upper half densely setose, except behind pronotal lobe, with setae slightly sparser on hypoepimeral area; ventrolateral half sparsely setose. Metanotum with tomentum uninterrupted, uniformly pale yellow. Propodeal triangle mostly glabrous, with (pale) setae restricted to small lateral patches. Metasomal terga with bands of off-white to pale-yellow tomentum. T1 with basal transverse band widely interrupted medially, arched, and continuous with (and indistinguishable from) lateral longitudinal band; apical transverse band separated into pair of rounded lobes medially; discal patch triangular (semicircular in some non-type specimens). T2–T4 with medially interrupted apical transverse bands, that of T2 with pair of basomedially convergent anterolateral extensions. S2–S3 with apical transverse bands of white tomentum.

SURFACE SCULPTURE. Labrum and clypeus with punctures equally dense (most i <1d); interspaces well defined, shining. Vertexal area densely punctate (most i <1d). Mesoscutum, mesoscutellum, and axilla with punctures more or less equally dense and nearly contiguous (most i<1d). Mesopleuron with punctures in upper half not much denser (most i<1d) than in ventrolateral half (most i≤ 1d); interspaces shining; punctures similar in size throughout. Discs of metasomal terga with punctures very fine, dense (i ≈1d), and evenly distributed; interspaces shining somewhat.

STRUCTURE. Labrum with pair of small subapical denticles, each preceded by discrete longitudinal ridge. Pronotal collar rather short (medial length ~⅔ MOD). Mesoscutellum moderately bigibbous. Axilla extending little if at all beyond midlength of mesoscutellum; tip visible but somewhat blunt, mesally unattached to mesoscutellum for less than ⅓ medial length of axilla; lateral margin relatively straight.

Female

T5 with broadly convex apical margin and large patch of off-white to pale-yellow tomentum on each side lateral to pseudopygidial area. Pseudopygidial area circular, with setae glossy, predominantly grayish brown, and sparser centrally; apical margin with row of dense, appressed and suberect coppery to silvery setae. Pygidial plate apically truncate. S4 with apical transverse band of white tomentum. S5 straight in lateral view, covered in brown tomentum and with apical fimbria of brown bristle-like setae.

Male

T5–T6 with medially interrupted apical transverse bands of off-white to pale-yellow tomentum. Pygidial plate relatively flat and apically rounded. S4–S5 each with apical/subapical fringe of dense, long (> 1 MOD), curved, coppery to silvery setae, not contrasting strongly with bands of preceding sterna.

Distribution

Ecuador and Peru, west of the Andes ( Fig. 1C ).

Ecology

Host records

One (female) specimen of T. buchwaldi at the AMNH (M.G.R. Database No. 2260) is pinned with a specimen identified by C.D. Michener as Florilegus purpurascens Cockerell, 1914 ( Hymenoptera : Apidae : Eucerini ), both of which were apparently taken from the same nest 14 km E of Tembladera in Cajamarca, Peru.

Floral records

Rightmyer (2006) reported this species on Bidens L. ( Asteraceae ) and Gossypium hirsutum L. ( Malvaceae ). Images on iNaturalist show this species visiting Ludwigia L. ( Onagraceae ). The label of one examined voucher specimen says “soybean var. trial bloom”.

Remarks

In his treatment of South American Triepeolus, Moure (1955) indicated that he was not familiar with T. megadelphus . However, Moure subsequently examined the holotype, in 1957—the year indicated on his determination label ( Fig. S9F in Supp. file 2)—and identified the specimen as T. buchwaldi but did not publish the synonymy. The authors of the present study agree with Moure’s designation, as the specimen does not exhibit any morphological features to suggest that it belongs to a separate species, so T. megadelphus is herein synonymized under T. buchwaldi .

Moure (1955) described T. aguilari based on a male specimen from Lima, Peru, claiming it to be similar to T. ancoratus Cockerell, 1916 from the southwestern United States. The types of both species are markedly different despite both belonging to the T. verbesinae species group, with the latter (USNM 534611) exhibiting a transversely oblong (as opposed to triangular) discal patch on T1 and complete (as opposed to medially interrupted) transverse bands on T1–T4. The metasomal tergal bands in T. buchwaldi are typically more widely interrupted medially in the female than male, and the patterns of pubescence exhibited by the holotype of T. aguilari do not differ markedly from those exhibited by the studied male type of E. buchwaldi —in both specimens, the metasomal tergal bands are only narrowly interrupted medially. Hence, the authors of the present study do not consider these to be distinct species, and T. aguilari is herein synonymized under T. buchwaldi .

Since Friese (1908) did not explicitly designate a holotype, one of the two studied syntypes —the male, which bears a red label that says “Type”—is herein designated as the lectotype of E. buchwaldi . The female, which is from the type locality and was identified as E. buchwaldi by Friese but is not labeled as a type, is recognized as a paralectotype.

Moure & Melo (2007) tentatively synonymized Epeolus xanthurus Cockerell, 1917 with T. buchwaldi and erroneously indicated the AMNH as the repository for the holotype of the former (the specimen is actually deposited in the USNM). Epeolus xanthurus is now correctly placed in Epeolus as a junior synonym of E. luteipennis Friese, 1916 (Onuferko 2019).

Figures

Fig. 1. Occurrence records (yellow circles) of species of Triepeolus Robertson, 1901 represented in South America. A. T. alvarengai Moure, 1955. B. T. atoconganus Moure, 1955. C. T. buchwaldi (Friese, 1908). D. T. cecilyae Packer, 2016. E. T. flavipennis (Friese, 1916). F. T. nemoralis (Holmberg, 1886). G. T. osiriformis (Schrottky, 1910). H. T. rufotegularis (Ashmead, 1900). I. T. tuberculifer Onuferko, Rightmyer & Roig-Alsina sp. nov.

Fig. 4. Head and mesosoma of female, oblique view. A. Triepeolus atoconganus Moure, 1955 (NHMUK NHMUK013620580). B. T. cecilyae Packer, 2016 (PCYU). C. T. buchwaldi (Friese, 1908) (AMNH M.G.R. Database No. 3707). D. T. rufotegularis (Ashmead, 1900) (USNM M.G.R. Database No. 1332). Blue arrows indicate dense, long (≥½ MOD), erect/suberect, minutely branched setae.

Fig. 6. Triepeolus buchwaldi (Friese, 1908). A. Female (AMNH M.G.R. Database No. 1328), habitus, lateral view. B, D. Female (AMNH M.G.R. Database No. 3707). B. Habitus, dorsal view. C. Male (INHS 387483), habitus, lateral view. D. Pseudopygidial area, dorsal view.

Fig. 9. Triepeolus cecilyae Packer, 2016, metasoma of male, ventral view. A. Holotype (PCYU). B. Non-type specimen from southern Peru (ZMB).