Bembix arnoldi Arnold, 1929

Gess, Friedrich W. & Gess, Sarah K., 2014, Geographical distributions of Bembix (Hymenoptera, Crabronidae, Bembicinae) in southern Africa, with notes on biology, Journal of Hymenoptera Research 36, pp. 53-130 : 61-62

Bembix arnoldi Arnold Fig. 1e

Bembex arnoldi Arnold, 1929: 353, figs 20, 20a, ♂ (Syntypes, Jeffrey’s Bay, Eastern Cape, South Africa, in TMSA) (in revision of southern African Sphecidae ); Arnold 1930: 21 (in checklist of Afrotropical Sphecidae ); Arnold 1936: 27, pl.1, fig. 8, ♀.

Bembex arnoldi [non] Arnold, 1929: 354, pl. 6, fig. 15, ♀ [= Bembix carinata F. Smith]

Bembix arnoldi Arnold, Lohrmann, 1948: 449 (member of arnoldi species group of Bembix ); Gess 1986: 151-152 (nesting, flower visiting, hunting and prey capture); Gess and Gess 1988: 246-247, Fig. 14.19 (habitat and hunting); Gess and Gess 1998: 35, Fig. 22.18 (habitat, hunting); Evans and O’Neil 2007: 183 (summary of nesting habits); not listed in R. Bohart and Menke 1976; Pulawski 2013: 8 (in catalogue of world Sphecidae sensu lato).

Note.

Arnold (1929: 353) and ( 1936: 27) gives the author of this species as Brauns but as Brauns never published the description (or even the name) and as Arnold clearly published the description on Brauns behalf (as is evident from his comments ( 1936: 27) then the author must be Arnold himself. The correct form is thus not Bembix arnoldi Brauns but Bembix arnoldi Arnold!

Brauns ( Arnold 1929: 354) recorded the species in addition from Jeffrey’s Bay. [This seems to have been in error, the female concerned being that of Bembix carinata Smith (see Arnold 1936: 28)]. Brauns’ observations were that this species is confined to sand dunes on the seashore.

Material examined.

SOUTH AFRICA: EASTERN CAPE: Kleinemonde [33.32S, 27.03E], ix.1956 (M.J.A. Cooke) [AMGS], 1 ♂; Port Alfred [33.36S, 26.55E], 1.ii.1959 (E.McC. Callan), 1 ♀ [AMGS]; Kasouga Dunes [33.39S, 26.44E], xii.1954 Cooke), 1 ♀ [AMGS]; Boknes (33.43S, 26.35E), 16.i.1984 (D.W. Gess), 1 ♀, 3 ♂♂ (on flowers of Phylohydrax carnosa (Hochst) Puff, Rubiaceae ) [AMGS]; same locality and date, (H.W. Gess), 2 ♀♀ (on flowers of Phylohydrax carnosa ) [AMGS]; same locality, 20.i.1984 (D.W. Gess), 2 ♀♀ (on flowers of Phylohydrax carnosa ) [AMGS]; same locality, 24.i.1984 (F.W. and S.K. Gess), 2 ♀♀, 6 ♂♂ (on flowers of Phylohydrax carnosa ) [AMGS]; same locality and date (R.W. Gess), 3 ♂♂ (on flowers of Phylohydrax carnosa ) [AMGS]; same locality, 9.i.1986 (D.W. Gess), 4 ♀♀ (on flowers of Phylohydrax carnosa ) [AMGS]; Zwartkops [now Swartkops] [33.52S, 25.36E], Port Elizabeth, 25.xi.1919 (collector variously given as C.B. Krüger or C.B. Kruger), 2 ♂♂ [AMGS], 1 ♂ [SAMC ex NMBZ]; Zwartkops, Algoa Bay, 25.xi.1921 (Dr Brauns), 1 ♂ [AMGS], 1 ♂ [SAMC ex NMBZ]; Zwartkops, Port Elizabeth, 25.xi.1921 (Dr Brauns), 2 ♂♂ [SAMC ex NMBZ], 1 ♂ [DMSA]. WESTERN CAPE: Port Beaufort [34.24S, 20.49E], 26.i.2004 (F.W. and S.K. Gess), 1 ♂ (visiting flowers of Scaevola plumieri (L.) Vahl, Goodeniaceae on dunes of seashore [AMGS].

Geographical distribution.

The species appears to have a strictly coastal distribution ( Fig. 2e ). At present it is known from the Eastern Cape, from Kleinemonde to Zwartkops near Port Elizabeth and from the Western Cape at Port Beaufort. At both Boknes and Port Beaufort the species was found frequenting the first line of supra-littoral dunes and visiting the flowers associated with these dunes.

Floral associations.

Recorded from two plant families: Rubiaceae ( Phylohydrax carnosa (Hochst.) Puff); Goodeniaceae ( Scaevola plumieri (L.) Vahl).

Nesting.

Unknown but most likely nesting in the supra-littoral dunes. At Boknes was repeatedly observed digging burrows on the seaward side of the fore-dunes.

Prey.

One record only, Diptera : Muscidae (on ocean wrack on tideline).

Figures

Figure 1. Bembix spp.: a Bembix albata, female, male b Bembix albicapilla, female c Bembix albofasciata, female, male d Bembix anomalipes, female, male e Bembix arnoldi, female, male f Bembix atrospinosa, female, male. (approximate lengths of females: a 21 mm; b 18.5 mm; c 17 mm; d 19.5 mm; e 17 mm; f 19.5 mm)

Figure 2. Distributions of collection records of Bembix spp.: a Bembix albata b Bembix albicapilla c Bembix albofasciata d Bembix anomalipes e Bembix arnoldi f Bembix atrospinosa.