Rediviva vogeli Melin and Colville, 2024

Melin, Annalie, Manning, John C. & Colville, Jonathan F., 2024, Species circumscription within the Rediviva neliana group (Hymenoptera: Melittidae), with the description of the new species Rediviva volgeli sp. nov. Melin & Colville, Zootaxa 5507 (2), pp. 245-284 : 254-261

Rediviva vogeli Melin and Colville , sp. nov.

urn:lsid:zoobank.org:act:4E1AB330-FEA8-4E6A-99A0-632942F6F816

Figs 4 , 7–10

Diagnosis. Female: Galea apical third spear-shaped, pointed apically, not acutely, spear-shaped ( Fig. 4A ), black hairs on disc of T3 with white apical hair bands ( Fig. 8C ). Male: Ventral margin of the apical plate of S8 with three shallow emarginations ( Fig. 7M ), integument of the metasomal terga 1–2 black ( Fig. 9C ), galea pointed apically, not acutely ( Fig. 4B ), hairs on median lobes of S7 yellow ( Fig. 7N ), ventral margin of the apical plate of S8 with three shallow emarginations with two distinct medial notches ( Fig. 7M ), black hairs or black hairs intermixed with yellow on disc of T2, T7 black hairs.

Etymology. This species is named after Professor Stefan Vogel (1925–2015), one of the world’s foremost floral ecologists, who discovered an entirely new pollination syndrome between oil-secreting host flowers and oil-collecting bees ( Neff & Simpson 2017). In particular, he was the first to recognise that Rediviva was the previously unknown pollinator of Diascia ( Scrophulariaceae ) in South Africa ( Vogel 1984).

Material examined (83 specimens)

Type material. [ 79 specimens] (all in SAMC): South Africa: Mpumalanga Province: HOLOTYPE: ♀: “ Lydenberg [Lydenburg] TVL. / Mauchsberg top / 2150 m 2530BA / 30 I 1988 / V. B. Whitehead ”; “ Wahlenbergia ”; SAM-HYM-B002790 . - Paratypes. 4 ♀ 13 ♂ / “ Lydenburg, TVL. / Mauchsberg Top / 2150 m 2530 BA / 30. 1. 1988 / V. B. Whitehead ”; “ Wahlenbergia ”; forelegs glued on card labelled individually: “743–744, 746, 748, 752, 757; SAM-HYM-B002915; 8 ♀ 6 ♂ / same data but “ 28. 1. 1988 ”; forelegs glued on card labelled individually: “745, 747, 749–750, 863; “ Rediviva / neliana Cockerell / det. / V. B. Whitehead / 20 XI 1990 ”; Genitalia and hidden sterna dissected stored in pinned microvial below specimen, SAM-HYM-B002914; 8 ♀ / “ South Afr. , Transvaal / 2530 BA / Top of Long Tom Pass / elev. 2150 m / 14 Feb 1987 / K. Steiner ”; forelegs glued on card labelled individually: “1690–1693, 1696–1699”; “ Wahlenbergia ”; forelegs glued on card labelled individually “284–290”; SAM-HYM-B002789; 1 ♂ / same data but “ 13 II 87 / V. B. Whitehead / Wahlenbergia ”; foreleg glued on card labelled individually “283”; SAM-HYM-B002791; 7 ♀ / same data but “ 14 II 87 ”; forelegs glued on card labelled individually “273–279”; SAM-HYM-B002792; 2 ♀ / “South. Afr., Natal / 8 km E. of Rd. 543 / on rd. to Lüneburg / 7 Mar 1990 / elev. 1490 m / K. Steiner ”, “ Corycium dracomontanum ”, SAM-HYM-B002948; 1 ♀ / same data but “ 1660 m 2730AD / 7 Mar. 1990 / V. B. Whitehead ”, “ Corycium dracomontanum ”, SAM-HYM-B002949; 1 ♀ 2 ♂ / “Transvaal / Mauchsberg / 2530 BA / 2150 m / 30 Jan 1988 / K. Steiner ” / SAM-HYM-B010506; 3 ♀ / same data but “ 28 Jan 1988 ”; “ Wahlenbergia ”; SAM-HYM-B010505; 1 ♂ / “ S.Afr. TVL / Lydenburg / Long Tom Pass / 13 II 87 / V. B. Whitehead / Wahlenbergia ”; foreleg glued on card labelled individually “281”; “ Rediviva / neliana Ckll / Det. / V. B. Whitehead / 30 XI 1987 ”; Genitalia and hidden sterna dissected stored in pinned microvial below specimen; SAM-HYM-B023552; 1 ♀ / South Africa, Mpumalanga, / 22.6 km southeast of / Mashishing (Lydenburg), Long / Tom Pass ( R37 ), road verge, / -25.14051, 30.60786, 2141 m, / 05 March 2020, A. Melin, / J.F. Colville, Host plant / Wahlenbergia ”. Free State Province: 5 ♀ / “OFS / Platberg / elev. 2140 m / 24 Feb 1985 ”; “ Diascia barberae ”; forelegs glued on card labelled individually “222–226”; SAM-HYM-B002851; 3 ♀ 1 ♂ / same data but “elev 2200 m / 23 Feb 1986 ”; forelegs glued on card labelled individually “219–220, 391, 382”; SAM-HYM-B002852; 1 ♂ / same data but “elev 2150 m ”; “ Wahlenbergia undulata ”; foreleg glued on card labelled individually “392”; SAM-HYM-B002853; 1 ♀ 4 ♂ / same data; forelegs glued on card labelled individually “221, 393–394, 396–397”; SAM-HYM-B002854; 1 ♂ / same data but “ 17 II 87 / V. B. Whitehead / W. undulata ”; foreleg glued on card labelled individually “385”; SAM-HYM-B002856; 1 ♀ / “ South Afr. , O.F.S. / 2828 DA / Goldengate Park / elev. 2300 m / 3 Feb 1988 / K. Steiner ”; “ Wahlenbergia / cuspidata ”; SAM-HYM-B010493; 3 ♀ / “OFS / Platberg / 2829 AC / elev. 2140 m / 17 Feb 1987 / K. Steiner ”; “ Wahlenbergia ; forelegs glued on card labelled individually “388–390”; “ Rediviva neliana / det. V. B. Whitehead / 20 Nov 1990 ”; SAM-HYM-B002855 [series to be split]; 1 ♀ / “O.F.S. / Golden Gate / Highlands Nat. Pk. / V. B. Whitehead / 11. 2. 1986 ”; “ Diascia / integerrima ”; foreleg glued on card labelled individually “213”; SAM-HYM-B002860 [series to be split]; 1 ♀ / “Clarens OFS / Golden Gate / Highlands N. Pk / 2150 m 2828 DA/ 3. 2. 1988 / V. B. Whitehead ”; “ Diascia / integerrima ”; foreleg glued on card labelled individually “762”; SAM-HYM-B003075 [series to be split] .

Additional material examined: 1 ♂ / “SAf. TVL / Lydenburg / Long Tom Pass / Summit / 16 II 1987 / V. B. Whitehead / Wahlenbergia ”; foreleg glued on card labelled individually “282”; SAM-HYM-B023553 [accession no. not valid] . 2 ♀ / “ South Afr. , Transvaal / 2350 BA / Top of Long Tom Pass / elev. 2150 m / 14 Feb 1987 / K. Steiner ”; “ Wahlenbergia ”; SAM-HYM-B002912 .

Description. ♀. Measurements. (n = 10): body length (BL) 10.23 mm (9.12–10.89 mm), inter-tegular distance 2.81 mm (2.70–2.92 mm), foreleg (FL) 9.03 mm (8.60–9.19 mm), FL: BL 0.89 (range 0.79–1.00), head width 3.92 mm (3.61–4.17 mm), head length 3.05 mm (2.79–3.28 mm), malar space (length: width) 0.32 (range 0.31–0.34). Integumental colour. Black except anterior surface of the antenna and the tips of mandible dark reddish-brown ( Fig. 8A ). Head. Labrum covered with long black unbranched hairs ( Fig. 8B ). Long black hairs on the clypeus with yellow branched hairs intermixed with unbranched black hairs on the paraocular area, supraclypeal area and frons, with branched black hairs on the vertex around the ocelli, with black and yellow hairs intermixed along outer eye margin. Galea pointed apically, not acutely, spear-shaped ( Fig. 4A ). Mesosoma. Punctures on disc of scutum moderately sparse, punctures greater than one diameter apart, remaining surface punctures less than a diameter apart, surface between punctures shiny; scutellum punctures less than a diameter apart (dense), surface between punctures shiny. Scutum, scutellum, metanotum, mesepisternum, propodeum covered in yellow branched hairs, with sparse erect branched black hairs on the disc of the scutum ( Fig. 8D ). Legs. Forelegs elongate, covered with yellow hairs, tarsus with dark brown to black hairs apart from the tibia and basitarsus of the foreleg with dark brown to black hairs, orange hairs on outer surface basitarsus, and dense oil-collecting black hairs on tarsomeres 2–5; middle leg with orange hairs on outer surface and dark brown-black hairs on the inner surface of the tibia and basitarsus; scopal hairs on the hind tibia and basitarsus covered in long orange hairs and basitarsal brush black ( Fig. 8A ). Metasoma. Yellow apical tergal hair bands on T1–T4 ( Fig. 8C ). Disc on T1 with sparse long sub-erect yellow hairs; disc on T2 covered in long yellow with median subapical patch of erect black hairs, discs on T3–T4 with black hairs, fimbriae of T5 black, yellow laterally, fimbriae of T6 black.

♂. Measurements. (n = 10): body length (BL) 8.7 mm (range 8.02–9.38 mm), inter-tegular distance 1.92 mm (range 1.73–2.08 mm), foreleg (FL) 6.06 mm (range 5.81–6.27 mm), FL: BL 0.70 (range 0.64–0.74), head width 3.48 mm (3.22–3.78 mm), head length 2.70 mm (2.45–2.91 mm), malar space (length: width) 0.32 (range 0.27–0.32). Integumental colour. Black except basitarsus and tibia of the hindlegs and basitarsus of the midlegs yellow ( Fig 9A ); antennae variable, all black to black with anterior surface reddish brown. Head. Labrum covered with long yellow unbranched hairs ( Fig 9B ). Yellow branched hairs on the frons, paraocular area, supraclypeal area and clypeus, with branched black hairs on the vertex around the ocelli, with black and yellow hairs intermixed along outer eye margin. Galea pointed apically, not acutely, spear-shaped ( Fig. 4B ). Mesosoma. Punctures on disc of scutum moderately sparse, punctures less than one diameter apart, surface between punctures shiny; scutum, scutellum, metanotum, mesepisternum, propodeum covered in yellow branched hairs, with sparse erect branched black hairs on the disc of the scutum ( Fig. 9D ). Legs. Covered in long, yellow branched hairs ( Fig. 9A ). Metasoma. Disc on T1 with sparse long sub-erect yellow hairs; disc on T2 with black or black hairs intermixed with yellow on disc and pale yellowish apical band, discs on T3–T5 black, yellow apical bands on T3–T6, fimbria on T6–T7 black ( Fig. 9C ). Median and lateral lobes of S6 ( Fig. 7O ) well developed, with translucent area on apical third; median lobes of S7 ( Fig. 7N ) long, spatulate, terminating in long-branched, yellow-orange hairs, lateral lobes large, striate, translucent; the long apical process of the S8 with slightly concave lateral margins ( Fig. 7M shown by black arrow), with sublateral yellow hairs, ventral margin of apical plate with three shallow emarginations and two distinct medial notches with lateral notches slightly pronounced to flat. Genital capsule ( Fig. 7P ) with gonostylus extending a little beyond the penis valves, with long unbranched yellow-orange hairs on the apical third.

Flight period. Early January to early March.

Host flower records. No oil-secreting host plants have been recorded for the population that occurs on Long Tom Pass. However, orchid pollinia have been noted on the forelegs of the females. Both males and females have been captured on the nectar host plants Wahlenbergia sp. The Platberg population has been collected from the oil secreting host plant Diascia barberae and the nectar host plant is W. undulata . At the nearby Golden Gate Highlands National Park population, R. vogeli have been recorded using D. integerrima as an oil host and W. cuspidata as a nectar host. Females from the population near the town of Lüneburg have pollinia attached to their basitarsus and have been recorded on the oil-secreting orchid Corycium dracomontanum .

Distribution. ( Fig. 10 ) Rediviva vogeli is known from four localities from the eastern part of Mpumalanga, extending down the Mpumalanga-Limpopo Escarpment ( Clark et al. 2011b) southwest towards Platberg (KwaZulu-Natal part of the Escarpment) and Golden Gate Highlands National Park (Main Drakensberg Escarpment), which is the western boundary of its known range. At the type locality, R. vogeli is known from a very limited, high-altitude montane area in the eastern part of Mpumalanga, on the summit of Long Tom Pass and Mauchsberg, at an elevation between 2150 m and 2209 m. The vegetation type is Long Tom Pass Montane Grassland within the Grassland biome ( Mucina & Rutherford 2006). The remaining three localities fall within the Grassland biome ( Mucina & Rutherford 2006) across several vegetation types, viz. Wakkerstroom Montane Grassland near Lüneburg, Basotho Montane Shrubland at Platberg, and Lesotho Highland Basalt Grassland and Northern Drakensberg Highland Grassland at Golden Gate Highlands National Park.

Comments. Rediviva vogeli is one of the four species considered as part of the R. neliana group. This species was previously considered a disjunct population of R. neliana ( Whitehead et al. 2008) but can be easily distinguished from R. neliana by the shape of the galea, the colour of the hairs on the disc of the T3 of females and the T2 of the males and the structure of the S8 (see Diagnosis above).

Figures

FIGURE 4. Comparison of the shape of the galea of both sexes (♀ left and ♂ right) for the following four Rediviva species: A–B: R. vogeli sp. nov.; C–D: R. neliana; E–F: R. politissima stat. rev.; G–H: R. steineri. Scale bar = 0.5 mm.

FIGURE 7. Ventral view of male S6–S8 and genital capsule in four Rediviva species: R. steineri (A: S8, B: S7, C: S6, D: Genital capsule), R. politissima stat. rev. (E: S8, F: S7, G: S6, H: Genital capsule); R. neliana (I: S8, J: S7, K: S6, L: Genital capsule), R. vogeli sp. nov. (M: S8, N: S7, O: S6, P: Genital capsule). Scale bar = 0.5 mm.

FIGURE 8. Female of Rediviva vogeli sp. nov.: A) Lateral view of habitus (scale = 1 mm); B) frontal view of head (scale = 0.5 mm); C) Dorsal view of metasoma (scale = 0.5 mm); D) Dorsal view of mesosoma (scale = 0.5 mm).

FIGURE 9. Male of Rediviva vogeli sp. nov.: A) Lateral view of habitus (scale = 1 mm); B) frontal view of head (scale = 0.5 mm); C) Dorsal view of metasoma (scale = 0.5 mm); D) Dorsal view of mesosoma (scale = 0.5 mm).

FIGURE 10. Distributions of the four species in the Rediviva neliana group. The following abbreviations for South African provinces: WC: Western Cape, NC: Northern Cape, EC: Eastern Cape, FS: Free State, MP: Mpumalanga, GP: Gauteng, KZN: KwaZulu-Natal. The following abbreviations for counties are LES: Lesotho and SWA: Eswatini.