Triepeolus cecilyae Packer, 2016

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 : 18-22

Triepeolus cecilyae Packer, 2016

Figs 1D , 4B , 7–9

Triepeolus cecilyae Packer, 2016: 2 (♂), figs 1–6.

Diagnosis

The following morphological features in combination tell T. cecilyae apart from all other South American Triepeolus : the frontal area, dorsum of the mesosoma, and both the upper and ventrolateral halves of the mesopleura have dense, long (clearly>½ MOD), erect/suberect, minutely branched setae ( Fig. 4B ) and the T3–T4 apical transverse bands are narrowed or narrowly interrupted medially ( Figs 7B , 8 ). Triepeolus cecilyae and T. atoconganus are the only South American species in the genus with long (≥½ MOD), erect/suberect setae on the upper face and much of the mesosoma, but in T. atoconganus these are shorter for the most part (with few exceeding 1 MOD in length) and less abundant, covering much of the upper but not ventrolateral halves of the mesopleura. Additionally, in T. atoconganus the T1–T4 transverse bands are all widely interrupted medially.

Etymology

The specific epithet (declined in the genitive case) honors Cecily Bradshaw, a friend of the taxonomic authority and advocate for (and supporter of) bee research ( Packer 2016).

Material examined

Primary type material

CHILE • ♂, holotype; Region I [sic, actually Arica y Parinacota Region], 30 km W of Zapahuira ; 24 Apr. 2001; R.E. Owen leg.; PCYU .

Non-type material

PERU • 1 ♂; Arequipa, Characato; 16.4669° S, 71.4753° W; 15 May 2022; Y.A. Calizaya leg.; PCYU • 1 ♀ (studied from image); same collection data as for preceding; 17 Jan. 2023; Y.A. Calizaya leg.; MUSA • 1 ♀ (studied from image); same collection data as for preceding; 17 Jan. 2023; Y.A. Calizaya leg.; PCYU • 1 ♀; Ica, 51.1 km E of Nazca ; 14.8104° S, 74.6660° W; 2 May 2011; Ohl, Krause, and Breitkreuz leg.; PCYU • 1 ♂; same collection data as for preceding; 2 May 2011; Ohl, Krause, and Breitkreuz leg.; ZMB • 1 ♀; same collection data as for preceding; 3 May 2011; Ohl, Krause, and Breitkreuz leg.; ZMB • 1 ♂; same collection data as for preceding; 3 May 2011; Ohl, Krause, and Breitkreuz leg.; UNMSM .

Redescription

MEASUREMENTS OF HOLOTYPE. Body length 10.6 mm; ITW 2.1 mm; head length 2.5 mm; head width 3.5 mm; fore wing length 9.0 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) and basal two-thirds reddish brown. Labrum with small orange spot basolaterally. F1 orange in part. F2 with orange spot basally in some non-type specimens. Pronotal lobe, tegula, anterior metasomal terga laterally, and S1 to some extent reddish brown. Fore wing membrane dusky subhyaline throughout except around third submarginal crossvein and second recurrent vein, where subhyaline. Hind wing membrane dusky subhyaline to hyaline. Coxae to some extent and trochanters to tarsi entirely reddish orange (meso- and metatibiae, including spurs, and metafemur to varying degrees dark brown/black in non-type specimens).

PUBESCENCE. Face with tomentum densest around antennal socket. Clypeus, upper paraocular and frontal areas, and vertexal area mostly exposed. Labrum, face around antennal socket, most of pronotum (including pronotal collar), and mesopleuron along posterior margin above base of mesocoxa (and just below pronotal lobe and scrobal groove in non-type specimens) with off-white, erect, minutely branched setae (clearly reaching more than ½ MOD in length). Clypeus, genal and vertexal areas, most of mesoscutum, mesoscutellum, axilla, most of mesopleuron, metapleuron, and propodeum laterally with dark brown/gray, erect, minutely branched setae (clearly reaching more than ½ MOD in length). Mesoscutum with well-defined paramedian band of pale-yellow, erect, minutely branched setae (tapering slightly toward but not attaining anterior margin in holotype; attaining anterior margin in some non-type specimens); with pale-yellow, appressed, branched setae restricted to posterior margin. Mesopleuron densely setose throughout, with off-white, appressed, branched setae around pronotal lobe. Metanotum with tomentum uninterrupted, dark brown/gray except for small patch of off-white tomentum laterally. Propodeal triangle mostly glabrous, with (dark brown/gray) setae restricted to small lateral patches. T1 with basal transverse band of off-white to pale-yellow tomentum widely interrupted medially, arched, and continuous with (and indistinguishable from) lateral longitudinal band; apical transverse band of pale-yellow tomentum separated into pair of rounded lobes medially; discal patch semicircular (triangular in some non-type specimens). T2–T4 with medially narrowed or narrowly interrupted apical transverse bands of pale-yellow tomentum, that of T2 with pair of faint lateral longitudinal bands of diffuse pale-yellow setae in holotype (with pair of well-defined basomedially convergent anterolateral extensions in some non-type specimens). S2–S3 with apical transverse bands of white tomentum, that of S2 interrupted medially (complete but narrowed medially in one non-type specimen).

SURFACE SCULPTURE. Labrum and clypeus with punctures equally dense (most i <1d); interspaces well defined, shining. Vertexal area densely rugose-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 dull due to tessellate surface microsculpture.

STRUCTURE. Labrum with pair of small subapical denticles, each preceded by longitudinal carina. Pronotal collar rather short (medial length ~⅔ MOD). Mesoscutellum moderately bigibbous. Axilla not extending 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 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 slightly downturned apically, with apical fimbria of brown bristle-like setae and dark brown tomentum laterally, posteriorly, and in apicomedial triangular area; S5 otherwise covered in off-white to pale brown tomentum.

Male

T5–T6 with complete or medially narrowly interrupted apical transverse bands of pale-yellow tomentum. Pygidial plate apically rounded and slightly downturned, with basal transverse ridge ill-defined and lateral margin somewhat sinuate. S4–S5 each with apical/subapical fringe of dense, long (> 1 MOD), curved setae; coppery to silvery laterally, brown and contrasting strongly with bands of preceding sterna medially.

Distribution

Arid regions of southern Peru and northern Chile ( Fig. 1D ).

Ecology

Host records

Packer (2016) suggested that Mirnapis inca Urban, 1998 ( Hymenoptera : Apidae : Eucerini ) might be the host of T. cecilyae based on its size and occurrence in the area where the holotype of the latter was collected.

Floral records

This species has been collected from Grindelia tarapacana Phil. ( Asteraceae ).

Remarks

Triepeolus cecilyae was described from a single, male specimen collected in northern Chile ( Packer 2016). Its status as a new species was based in part on morphological comparisons to four specimens from Peru (two females and two males, all from the same locality and collected within a two-day period) tentatively identified by the author as T. atoconganus (L. Packer, personal communication, 2023). These specimens and the holotype of T. cecilyae were personally examined by TO, and all appear to be conspecific. One of the diagnostic features of T. cecilyae identified by Packer (2016) is that the T3 apical transverse band is complete (as opposed to interrupted medially). Additionally, in T. cecilyae S3 was described as “uniformly covered in pale hairs”. In the two male specimens from Peru, the bands on the metasomal terga and sterna were partly stained dark brown/black (presumably due to poor preservation) when received and initially examined by TO. Their original coloration was restored by applying small pieces of tissue paper dampened with 70% ethanol to the dorsal and ventral surfaces of the metasoma for several minutes. This treatment revealed that the T3–T6 apical transverse bands are complete in one of the two males from Peru ( Fig. 8B ) and the T3–T4 bands are only narrowly interrupted medially in the other. Additionally, in both specimens the metasomal sterna, including S3, were revealed to be extensively covered in white tomentum, as in the holotype of T. cecilyae ( Fig. 9 ). Although the T1–T4 apical transverse bands are all interrupted medially in the two females ( Fig. 7B ), they are more narrowly interrupted than in what is understood to be the female of T. atoconganus ( Fig. 5B ). Three additional specimens (two females and one male) have since been discovered (also in Peru but closer to the type locality in Chile), and in the two females some of the metasomal tergal bands are complete albeit narrowed medially whereas the rest are narrowly interrupted medially. Another feature of T. cecilyae originally considered to be diagnostic is that the legs are entirely reddish orange from the trochanters to tarsi, but among the now seven known non-type specimens from Peru there is continuous variation in the degree of dark brown/black coloration on the meso- and metatibiae and metafemora, which range from almost entirely reddish orange to mostly dark brown/black.

The eight known specimens are far more similar to one another morphologically than to any studied representatives (including the lectotype) of T. atoconganus , agreeing with the present diagnosis for T. cecilyae . Most notably, in these specimens the mesosoma is more extensively and obviously “hairy” than that of T. atoconganus and the T3–T4 apical transverse bands are at most only narrowly (as opposed to widely) interrupted medially. Further suggesting conspecificity is that all known collection localities (in Chile and Peru) are in the Atacama Desert and outlying arid areas along the Pacific coast. Based on known records, adults of T. cecilyae are active in summer and autumn (January to May).

Given the discovery of these additional exemplars of T. cecilyae , a re-description of this species is warranted. The female of T. cecilyae is described here for the first time.

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. 7. Triepeolus cecilyae Packer, 2016. A–B, D. Female (PCYU). A. Habitus, lateral view. B. Habitus, dorsal view. C. Holotype, ♂ (PCYU), habitus, lateral view. D. Pseudopygidial area, dorsal view.

Fig. 8. Triepeolus cecilyae Packer, 2016, metasoma of male, dorsal view. A. Holotype (PCYU). B. Non-type specimen from southern Peru (ZMB).

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

Fig. 5. Triepeolus atoconganus Moure, 1955. A, D. Female (UNMSM MHN 1350/M.G.R. Database No. 1333). A. Habitus, lateral view. B. Female (NHMUK NHMUK013620580), habitus, dorsal view. C. Male (NHMUK NHMUK013620577), habitus, lateral view. D. Pseudopygidial area, dorsal view.