Plesianthidium (Spinanthidium) calescens Cockerell
Creators: name: Eardley, Connal
name: Griswold, Terry
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Megachilidae
Plesianthidium
Plesianthidium calescens

description: Plesianthidium (Spinanthidium) calescens (Cockerell)
(Figs 19–21)
Dianthidium calescens Cockerell, 1921: 208 –209 (holotype—♀‘Montague, C.C., Oct. 1917 (E.P. Phillips) South African Museum’ (type depository unknown) South Africa).
Dianthidium (Spinanthidium) calescens: Mavromoustakis 1951: 980 –981.
Spinanthidium (Spinanthidium) calescens: Pasteels 1969: 50.
Plesianthidium (Spinanthidium) calescens: Gess et al. 1997: 84.
Discussion. The holotype was not located in the Iziko South African Museum, where it was deposited, or in any other museums whose material was included in this study, and therefore has not been studied. The species identity is based on Pasteels (1985) and the original description which described P. calescens as closely related to P. trachusiforme differing in lacking distinct teeth on the clypeus. Other elements of the description that in combination preclude it being any other species of Plesianthidium include mostly light vestiture, densely punctate clypeus, clypeal margin crenulated and integument black without light apical margins of terga.
Diagnosis. The combination of rounded preoccipital ridge, relatively small body size (length ≤ 10 mm), integument black without lighter apical tergal margins, mostly light pubescence, clypeus densely punctate and clypeal margin crenulate will distinguish female P. calescens from all other Plesianthidium. Within the subgenus Spinanthidium the densely punctate clypeus alone will identify P. calescens. Males can be recognized by the combination of preoccipital ridge rounded, T7 with slender medial spine extending posteriorly beyond lateral spines (Figs 20 a, b) and apical comb on S4. The structure of S8 is unique (Fig. 20 e).
Plesianthidium calescens in general looks like P. trachusiforme, P. neli and P. calvini. However, the metasomal terga are completely black and the lower edge of the clypeus is crenulate.
Description. Female. Lengths: face 3.2–3.4 mm; scutum 2.5–2.8 mm; forewing 8.0– 8.5 mm; body 9.2–10.0 mm. Integument black. Pubescence mostly white or off-white but vertex, scutum (Fig. 19 a) and scopa orangish. Metasomal terga without distal fasciae. Preoccipital ridge rounded; distance between lateral ocellus and preoccipital ridge 1.5x ocellar diameter; supraclypeus distinctly convex; clypeus distinctly convex, densely punctate, not modified ventrally, ventral edge crenulate; mandible with three distinct teeth; maxillary palpus 2- segmented; scutum very densely punctate; tegula denely punctate medially; propodeum mostly punctate; T2–T3 without distal fasciae, punctate distally; T6 expanded posterolaterally, without mediolongitudinal carina.
Male. Lengths: face 3.0– 3.3 mm; scutum 2.5–2.9 mm; forewing 7.8–8.5 mm; body 8.4–10.2 mm. Integument mostly black, clypeus black or partially to entirely yellow (Figs 19 d–f). Pubescence mostly white or off-white (Fig. 19 c); metasomal terga without distal fasciae. Preoccipital ridge rounded; distance between lateral ocellus and preoccipital ridge 1.5x ocellar diameter; supraclypeus distinctly convex; clypeus distinctly convex, densely punctate; mandible with three distinct teeth; maxillary palpus 2-segmented; scutum densely punctate medially, dull between punctures; tegula densely punctate; propodeum mostly punctate; hind trochanter without ventral spine; T2–T5 without distal fasciae; T6 without mediolongitudinal carina, with large posteromedially tubercle, with distinct lateral spines, narrow distal margin impunctate, without distal flange; T7 posterior edge tridentate moderately large lateral and median teeth, all spines narrow, median blunt, lateral pointed (Figs 20 a, b); S4 wide black apicomedian comb; S5 posterior edge strongly concave; S6 generally convex, posteriorly directed protuberances posterolaterally, some with narrow concavity posteromedially (Fig. 20 c); S7 disc short, with broad, concentric posterior concavity (Fig. 20 d); S8 with disc long, apical margin broadly truncate, sides straight (Fig. 20 e); gonostylus concave apicolaterally (Fig. 20 f).
Distribution (Fig. 21). Plesianthidium calescens is apparently endemic to Namaqualand and the South- Western Cape, both in South Africa.
Associated plants. Arctotheca calendula, Ballota africana, Berkheya fruticosa, Hermannia cuneifolia, Hermannia disermifolia, Hermannia cf. disermifolia, Hermannia scordifolia, Hermannia trifurcata, Hermannia sp., Lebeckia sericea, Lebeckia sp., Pteronia divaricata, Pteronia incana, Wahlenbergia prostrata.
Material examined. South Africa. Hell’s Kloof road, Richtersveld National Park, 28.18S 16.15E, 2008. x.12, C. Eardley (1♂ SANC 19284); Concordia, 4 km N, 29.5009S 17.9383E, 2007. ix.13, T. Griswold (1♀ BLCU 723220); Kliphoogte, 29.0656S 17.4019E, 2011. ix.14, L. Packer (1♂ PC 15277 D11); Goegap Nature Reserve, Springbok, 29.38S 17.59E, 1987. x.15–21, F.W. Gess (1♂ AMGC 2845); idem, 1985. viii.20–ix.7, 1987. x.9–15, M. Struck (3♀ 8♂ SANC 0 4038, 0 4034, 0 4044, 0 8047, 0 8048, 0 8051, 19266, AMGC 2845); Springbok, 29.6606S 17.8936E, 1966. ix.7, C.D. Michener (1♂ BLCU 724918); Wallekraal, 7 km WNW Hondeklip Bay road, 30.22S 17.28E, 1992. ix.14–16, F.W. Gess (2♀ 1♂ AMGC 2853, 2875, 2876); Wallekraal, 30.3901S 17.5135E, 1950.x, Spinanthidium calescens Ckll. J. Pasteels det. 1978 (1♀ 1♂ BLCU 724871, 724925); De Kruis, 1.5 km SW, 30.3873S 18.118E, 2007. ix.17, T.L. Griswold (1♀ 1♂ BLCU 722182, 722183); De Kruis, 14 km S, 30.503S 18.1367E, 2007. ix.17, T.L. Griswold, on Lebeckia sp. (1♂ BLCU 722250); Studer's Pass near Garies, 30.4333S 17.0500E, 2007. ix.16, C.D. Eardley T. Griswold (3♀ 2♂ BLCU 723029, 723030, 723032, 723033, SANC 19207); Wallekraal, 1950. x.1 (2♀ 4♂ SAMC 006908); Bowesdorp, 1931. xi.1 (1♂ SAMC 004413); Kamieskroon, 1930. ix.1 (1♀ SAMC 004113); Kamieskroon, near Dassiefontein farm, 30.09S 17.59E, 1990. x.1, C.D. Eardley (1♀ BLCU 724926); Kamieskroon, 30.13S 18.03E, 1994. x.9–11, 1995. ix.28, F.W. Gess (2♀ 2♂ AMGC 2858, 2859, 2860, 2861); Kamieskroon 3 km E, 30.11S 17.57E, 2008. x.16, C. Eardley (1♂ SANC 19280, 19281); Bakleikraal, Kamieskroon, 30.13S 18.03E, 1994. x.9–11, F.W. Gess (1♂ AMGC 2858); Kamiesberg Pass, 30.1880S 17.9916E, 2012. ix.25, C.D., Eardley (1♂ SANC 19283); Dassiefontein farm, 1990. x.1, 2001. ix.16–17, 2007. ix.16, C.D. Eardley (4♀ SANC 0 4032, 19272, 19277, 19282); Leleifontein, 30.2332S 18.4647E, 2002. x.14, C. Mayer (1♀ SANC 19278); Botterkloof Pass, 31.48.50S 19.15.50E, 2004. x.4, M. Hauser (1♀SC); Vanrhynsdorp, 31.36S 18.45E, 1927. viii.1–31, H. Brauns (1♀ 4♂ AMGC 2837, 2838, 2839, 2840, 2841); Vanrhynsdorp, near waterfall, 31.47S 18.45E, 2005. ix.15, C. Eardley (1♂ SANC 19274, 19275, 19276); Niewoudtville falls, 5 km N Nieuwoudville, 31.20S 19.10E, 1990. ix.28, F.W. Gess (2♀ 5♂ AMGC 2846, 2847, 2848, 2849, 2850, 2851, 2852); Nieuwoudtville Falls, 6.5 km N Nieuwandtville, 31.3197S 19.1174E, 2007. ix.18, T.L. Griswold (1♀ BLCU 722289); Skuinshoogte Pass, Nieuwoudtville, 31.16S 19.08E, 1994. ix.23–30, F.W. Gess (2♀ 3♂ AMGC 2854, 2855, 2856, 2857); Nieuwoudtville, 7 km W, 31.3766S 19.0193E, 2002. x.9, F.D. Parker M.E. Irwin (3♀ BLCU 724930, 724931, 724932); Witwater, 30.2319S 18 135239E, 2003. v.29, 2003.ix–x, 2004. x.2, C. Mayer (7♀ 2♂ KC); Papkuilsfontein farm, 20 km S Nieuwoudtville, 31.33.16S 19.08.31 E, 2006. x.17, 2007. ix.9, M. Kuhlmann (1♀ 3♂ KC); Engelspunt, near, 31.14.08S 18.58.23E, 2006. x.14, K. Timmermann (1♂ KC); Nieuwoudtville Flower Reserve, 31.22.18S 19.08.58 E, 2006. x.19, M. Kuhlmann (1♀KC); Remhoogte, 30.2351S 18.16536E, 2002. x.14, 15. 2003.ix, C. Mayer (2♀ 1♂ KC); Leliefontein, 30.23169S 18.1626E, 2003.viii–ix, 2004.ix–x, C. Mayer (2♀ 5♂ KC); Keiski Mountains, 5 km S farm Nooiensrivier, 31.45.47S 19.50.17E, 2009. x.4, 2010. viii.29, M. Kuhlmann (2♀ 6♂ KC); Avontuur farm, 12 km NW Nieuwoudtville, 31.16.18S 19.02.55 E, 2009. ix.1, M. Kuhlmann (1♂ KC); Doringrivier, near Nieuwoudtville, 31.18S 19.07E, 1990. ix.28, C. Eardley (1♂ SANC 19285); Papkuilsfontein farm, 15 km S Nieuwoudtville; 31.546S 19.15783E, 2002. x.9, F.D. Parker M.E. Irwin (1♀ BLCU 724928); Pakhuis Pass, 32.1443S 19.0338E, 1987. ix.7, C.D. Eardley (5♂ SANC 0 4035, BLCU 724921); idem, 2007. ix.20, T.L. Griswold (2♂ BLCU 722533, 722537); Biedouw Valley, 32.1402S 19.2668E, 1987. ix.5–7, 2007. ix.20, C.D. Eardley T.L. Griswold (2♀ 1♂ BLCU 722877, 724920, 724924); Clanwilliam, 32.1802S 18.8877E, 1928.ix, H. Brauns (1♀ BLCU 843432); Biedouw Valley, Clanwilliam, 32.1333S 19.2333E, 1987. ix.5, C.D. Eardley (4♀ 6♂ SANC 04037); Wuppertal, 32.2833S 19.2166E 1987. ix.8, C.D. Eardley (1♂ SANC 04036); Clanwilliam, 2.5 km NW, 32.1562S 18.868E, 2008. x.19, T.L. Griswold (1♀ BLCU 752034); Skurfkop, 0,7 km N station, 1978. x.25, V. Whitehead (1♀ 1♂ SAMC 004411); Skurfkop, 2 km station, 1978. x.25, V. Whitehead (1♂ SAMC 004412); Skurfkop, near, 31.9227S 18.6311E, 2005. ix.20, C.D. Eardley (1♂ SANC 19274); Trawal, 15 km SSW, 32.0038S 18.58E, 2007. ix.21, T. Griswold (4♂ BLCU 722988, 722990, 722991, 723006); Liberty farm, 50 km N Ceres, 32.54S 19.27E, 1990. ix.27, C.D. Eardley (1♀ BLCU 724927); Ratelfontein and Olaf Bergfontein, between, 32.01S 18.33E, 1995. x.7–8, F.W. Gess (2♀ 11♂ AMGC 2862, 2863, 2864, 2865, 2866, 2867, 2868, 2869, 2870, 2871, 2872, 2873, 2874); Ratelfontein, near, 31.56S 18.31E, 2007. ix.21, C. Eardley (1♂ SANC 192790); Ratelfontein E, 32.02S 19.39E, 2011. ix.24, C. Eardley (1♂ SANC 19253); Citrusdal, 8 km. N, 1961. ix.1 (1♀ SAMC 006911); Leipoldtville, Elands Bay, 1947. x.1, 1948. xi.1 (1♀ 1♂ SAMC 0 0 6912, 006924); Rooikloof farm, 4 km S Sutherland, 1986. ix.30, V. Whitehead (1♂ SAMC 006910); Lambert’s Bay, 40 km S, 1999. x.30, M. Halada (4♀ 2♂ SC); Lambert’s Bay S, 1999. x.28, M. Snizek (2♀SC); Sutherland, 5 km N, 32.3494S 20.6694E, 2004. x.4–24, M.E. Irwin F.D. Parker (2♂ FDP 751392, 750959, 736555); West Coast Fossil Park (3 km W Langebaanweg), 2002. ix.4–11, S. van Noort D. Lawson E. Bartnick (5♀ SAMC 0 18310, 0 18490, 0 18572, 0 18581, 018658); Anyskop farm (4 km W Langebaanweg), 2002. ix.4–11, S. van Noort D. Lawson E. Bartnick (8♀ SAMC 0 18734, 0 18735, 0 18736, 0 18737, 0 19394, 0 19395, 019697); Anyskop farm (5.5 km W Langebaanweg), 2002. ix.4–25, S. van Noort D. Lawson E. Bartnick (7♀ SAMC 0 18992, 0 19250, 0 19396, 0 19599, 0 19696, 0 19698, 020151); Langberg farm (3 km W Langebaanweg), 2002. ix.4–25, S. van Noort D. Lawson E. Bartnick (6f# 1♂ HYM- 0 18038, 0 18787, 0 18788, 0 18789, 018993); West Coast Fossil Park, (4 km W Langebaanweg), 2002. ix.4–25, S. van Noort (17♀ 1♂ SAMC 0 18986, 0 18987, 0 18988, 0 18990, 0 18991, 0 19034, 0 19693, 0 19391, 0 19392, 0 19393, 0 19694, 0 19695, 022983); Dragonridge, Fynbos Estate, 2010. vii.30–ix.28, S. van Noort (4♀ SAMC 020551); Raubenheimer Dam, near Oudtshoorn, 33.24S 22.17E, 1972. x.10, C.F. Jacot-Guillarmod (4♂ AMGC 2842, 2843, 2844); Robertson, 14 km NW junction R60, 33.7775S 19.7615E, 2002. x.7–13, F.D. Parker M.E. Irwin (1♀ BLCU 724933); Riverhuis farm, 14 km NW Robertson on R60, 33.7778S 19.7597E, 2004. ix.22–29, M.E. Irwin F.D. Parker M. Hauser (3♂ FDP 735980, 736555); Montegu, 6 km SE, 33.8331S 20.17333E, 2004. ix.22–30, M.E. Irwin F.D. Parker M. Hauser (1♂ FDP 755083); Montegu, 1919. x.1, Tucker (1♀ SAMC 004414); Kommetjie, 34.1318S 18.3366E, 1972. x.12, J.G. Rozen R.J. McGinley C. Thompson (1♂ BLCU 724919).
description: Published as part of Eardley, Connal & Griswold, Terry, 2015, Taxonomic revision of Plesianthidium Cameron (Apoidea: Megachilidae: Anthidiini), an endemic southern African bee genus, pp. 1-56 in Zootaxa 3973 (1) on pages 33-37, DOI: 10.11646/zootaxa.3973.1.1, http://zenodo.org/record/288925