Anthidioma " chalicodomoides PASTEELS, 1984

Kasparek, Max & Kuhlmann, Michael, 2024, Do the members of the rare African bee genus Anthidioma (Megachilidae, Anthidiini) deserve distinct genus status?, Linzer biologische Beiträge 56 (1), pp. 111-120 : 113-116

" Anthidioma " chalicodomoides PASTEELS, 1984 ( Figs 1-3 )

Holotype (not examined). Female, South Africa, Cape Province, Clanwilliam, B. Don (Biedouw) Valley, 25.ix.1977, B. V. Whitehead leg., Iziko South African Museum , Cape Town, South Africa (data after PASTEELS 1984).

M a t e r i a l e x a m i n e d (all South Africa): 15 km NW Nieuwoudtville, Farm Zoetfontein E, Fynbos (31°14'05''S 19°02'50''E), 775 m, 07.x.2022, 1♀, M. Kuhlmann leg. ( CMK, mk1352) ; Ibid .; 11.viii.2023, 1♁ ( RCMK: zmk059) ; Roggeveld Mts. , 2km SE Farm Allemansdam (31°49'32''S 19°59'55''E), 1290 m, 20.09.2022, 2♀♀, M. Kuhlmann leg. ( SCMK: zmk060, zmk061) ; 15 km NW Nieuwoudtville, Farm Engelsepunt , Fynbos (31°14´31´´S 18°59´08´´E), 830 m, 24.ix.2003, 1♀, K. Timmermann leg. ( RCMK) ; 12 km NW Nieuwoudtville, Farm Avontuur , Fynbos (31°16´18´´S, 19°02´55´´E), 770 m, 10.ix.2009, 1♀, M. Kuhlmann leg. ( RCMK) ; Cederberg Mts. , road to Algeria, Olifants River bridge (32°21´55´´S 18°57´06´´E), 150 m, 8.ix.2017, 3♀♀, M. Kuhlmann leg. ( RCMK) .

D i a g n o s i s: In accordance with PASTEELS (1984) and GRISWOLD & GONZALEZ (2013), the female can be recognized by the following combination of characters: body integument mostly black with rich long pubescence; clypeus with strong longitudinal ridges on the disc and without a thickened distal rim; scutum, scutellum, and terga densely punctate; and T 6 vertical in profile, with the distal margin medially projected. The male, described here for the first time, is characterised by its black body integument with rich pubescence (as in the female); fine integumental punctation throughout; long, waved and hooked hairs on S3; a small, black comb next to the middle of S5, and a stronger black comb at the apex of a lateral arm of S3.

D e s c r i p t i o n: The female is re-described here, while the hitherto unknown male is described for the first time.

F e m a l e: 8–9 mm. Head: Clypeus with strong, coarsely punctate, protruding longitudinal ridges ( Figure 2A ); apical part abruptly sloping inward; lower end with smooth, triangular surface; mandible slender, shining with small, shallow, scattered punctures ( Figure 3A ); strong apical, subapical, and uppermost teeth, and 4–5 minute teeth in between; antenna black; dense, long white hairs on lower face and lower gena, obscuring the sculpture, especially the clypeus; vertex hairs less dense, greyish-brown. Mesosoma: Black, scattered greyish hairs, but dense white pubescence on mesepisternum; scutellum and axillae crescent-shaped in dorsal view, median scutellar emargination absent; in profile, scutellum rounded in the middle and angulate laterally; very little overhanging propodeum; propodeum shagreened; pronotal lobe low, carinate. Metasoma: Black, terga with scattered greyish pubescence, denser laterally ( Figure 2C ); hairs on T 4– T 6 dark brown; T 1– T 3 almost equally wide, T 4– T 6 tapering towards apex; punctation fine, uniform, interstices up to one puncture diameter, but mostly less; no conspicuous distinction between disc and depression; smooth apical margin about one antennal width; edges protrude slightly upwards; T 6 vertical in profile, distal margin horizontally projecting, small apical median emargination; scopa golden except for some grey bristles beneath horizontal projection of T 6. Legs: Black, with greyish to light yellow-brown pubescence; inner faces of basitarsi with dark yellow-brown bristles.

M a l e. 9 mm. Black without light maculation ( Figure1 ); long white, greyish and yellowish pubescence. Head: Long, dense pubescence on lower face, silvery on clypeus, yellowish grey around antennal sockets, on lower gena, and on preoccipital ridge; scattered yellowish grey hairs on vertex; clypeus obscured by hairs; mandible black with three strong teeth separated by sharp incisions ( Figure 3B ); uppermost tooth the strongest; antenna black. Mesosoma: As in female; pronotal lobe low with shallow lamella. Metasoma: Similar to female. T 6 and T 7 with deep median emargination of the apical margin; S2 with apical fringe of long hairs; S3 with two rows of modified hairs: the inner row with corkscrew-like hairs, the outer row with longer, apically hooked hairs ( Figure 3D ); S4 with median, deep V-shaped incision; S5 with a small black comb on each side of the middle (distance between combs approximately 3.5 comb-widths) and a strong black comb at the apex of a short lateral arm ( Figure 3E ); inner comb width approximately 12, outer comb with approximately 14 digits); hidden S7 deeply, and S8 shallowly bilobed. Genitalia ( Figure 3E ): Penis valves slender, not fused, tapering toward the apex; apex acute; gonocoxite slender; gonostylus leaf-shaped, slightly curved at the sides, protruding far beyond penis valve. Legs: Black, with long reddish-yellowish hairs; inner face of hind basitarsus densely covered with reddish bristles.

G e n e t i c A n a l y s i s. We obtained the COI gene sequences of three females ( SCMK: ZMK060, ZMK061; CMK: MK1352), all with a complete set of 658 base pairs (bp), and fully barcode-compliant as per BOLD quality standards.

In the identification tool provided by BOLD, the top 100 nearest neighbours revealed 21 species, with 71.4% belonging to Pseudoanthidium , 19.0% to Afranthidium , and 4.8% each to Pseudoheriades (Osmiini) and the Nearctic Trachusa mitchelli . All hits with a genetic match of>88% belonged to the Pseudoanthidium scapulare group.

The analysis of phylogenetic relationships using the Neighbor Joining ( NJ) methodology revealed that " Anthidioma" chalicodomoides is unambiguously nested within the Pseudoanthidium clade ( Figure 4 ). Its closest relatives are the members of the Pseudoanthidium scapulare and P. ochrognathum groups, with " Anthidioma" chalicodomoides placed basally to them. Afrotropical relatives include species whose identity still needs to be confirmed. Due to the high number of undescribed species in Pseudoanthidium , a sound subgeneric division is not yet possible. The Palaearctic taxa for which genetic data were available, could be assigned to seven different lineages.

D i s t r i b u t i o n a n d h a b i t a t: The species seems to be endemic to the Fybnos region of southern Africa, occurring between the Cederberg Mts. (Clanwilliam area) in the south, the Roggeveld Mts. south of Calvinia in the east and the Bokkeveld plateau (Nieuwoudtville vicinity) in the north (Figure 5). It was found predominantly on sandy soils with typical Fynbos vegetation, characterised by evergreen, hard-leaved Mediterraneantype shrubland. It was collected visiting the flowers of Asteraceae for pollen, indicating an apparent oligolectic behaviour.

T a x o n o m i c c o n c l u s i o n o n g e n e r i c s t a t u s: Based on the morphological and genetic results, we transfer the two described species of Anthidioma , A. chalicodomoides and A. murina , to the genus Pseudoanthidium as follows:

Genus: Pseudoanthidium FRIESE, 1898

Syn.: Anthidioma PASTEELS, 1984

Pseudoanthidium chalicodomoides (PASTEELS, 1984)

Pseudoanthidium obibense (GRISWOLD & GONZALEZ, 2013)

These two species seem to be closely related with the Palaearctic Pseudoanthidium scapulare and the P. ochrognathum groups.

Figures

Fig. 1. Habitus of Pseudoanthidium chalicodomoides PASTEELS, 1984, from South Africa. A. Female; B. Male.

Fig. 2. Pseudoanthidium chalicodomoides PASTEELS, 1984. A. Face of the female. B. Face of the male; C. Terga the of female. D. Terga of the male.

Fig. 3. Pseudoanthidium chalicodomoides (PASTEELS, 1984), from South Africa. A. Female mandible. B. Male mandible. C. Male genitalia. D. Corkscrew-like and apically hooked hairs on sternum 3 (S3) of the male. E. Sterna of the male with modified hairs on S3 and black combs on S5 (white arrows).

Fig. 4. Genetic relationships within the genus Pseudoanthidium as inferred from the DNA sequences of the barcoding region of the mitochondrial COI gene. Five selected species each of the genera Anthidium and Afranthidium were used as outgroup. For the sake of clarity, the sequences of closely related species were collapsed and classified according to their geographic origin.