Scrapter oxalis sp. nov.

urn:lsid:zoobank.org:act: ECBEF593-24AE-4B7C-B6CF-67A6C53A7302

Figs 2–3, 16–18, 23–28

Diagnosis

The female of S. oxalis sp. nov. can be separated from that of all other species in this group by the following character combination: scutellum relatively small, distinctly convex and shiny (Fig. 16D), propodeum dorsolaterally (lateral to the matt propodeal triangle) very finely shagreened and matt, hair on posterior surface shorter than length of basal area (Fig. 16D), foreleg blackish-brown, sometimes femur apically slightly dark yellowish-brown, apical tergal depressions narrow and brownish translucent without reddish discoloration of the adjacent apical area of the disc, disc of T2 finely and sparsely punctate (Fig. 16B).

The male is characterized by the propodeum densely covered with thick, plumose hair of ± equal length (Fig. 17B), foreleg completely dark brown to blackish, sometimes to a small extent distitarsus and apical parts of mediotarsi orange-brown (Fig. 17A), hind tibia apicomedially strongly swollen, hairs apically on inner side relatively short (Fig. 18A), S3-S5 with dense apical hair fringes (Fig. 17D), genitalia as in Fig. 18B.

Etymology

The specific epithet refers to the specific host plants of the genus Oxalis ( Oxalidaceae) of this bee species.

Type material (17 specimens)

Holotype SOUTH AFRICA • ♂; Knersvlakte, along Gemsbokrivier-Pad; 195 m a.s.l.; 31°26′40″ S, 18°56′23″ E; 5 Jun. 2013; M. Kuhlmann leg.; SANC.

Paratypes SOUTH AFRICA • 1 ♂; Gemsbokrivier-Pad, 4.5 km NE of Grootdrif, Road Side; 170 m a.s.l.; 31°25′54″ S, 18°55′16″ E; 20 May 2013; M. Kuhlmann leg.; NHML • 2 ♂♂; same data as for preceding; 28 May 2013; M. Kuhlmann leg.; RCMK • 1 ♂; same data as for preceding; 5 Jun. 2013; M. Kuhlmann leg.; RCMK • 3 ♀♀, 4 ♂♂; same data as for preceding; 10 Jun. 2013; M. Kuhlmann leg.; RCMK • 3 ♂♂; same data as for preceding; NHML • 1 ♂; Knersvlakte, along Gemsbokrivier-Pad; 195 m a.s.l.; 31°26′40″ S, 18°56′23″ E; 5 Jun. 2013; M. Kuhlmann leg.; RCMK .

Description

Female

BODY LENGTH. 6.5–7.5 mm.

HEAD. Head as wide as long. Integument black, except part of mandibles dark reddish-brown. Face sparsely covered with relatively long, yellowish-grey, erect hair (Fig. 2). Clypeus strongly convex with fine and very sparse (i= 2–5 d) punctation; surface between punctures smooth and shiny (Fig. 2). Malar area medially narrow, almost linear. Antenna dorsally dark brown, ventrally dark yellow.

MESOSOMA. Integument black, tegulae dark brown. Mesoscutal disc between punctures finely reticulate and partly matt; disc finely, relatively shallowly and sparsely (i= 2d) punctate (Fig. 16C). Metanotum slightly shorter than basal area of propodeum, apically with narrow and indistinctly carinate depression (Fig. 16D). Propodeum basally very indistinctly and finely carinate (Fig. 16D). Mesoscutum with short; scutellum, metanotum, mesepisternum and propodeum with long, sparse, greyish to yellowish, erect hair (Fig. 16A).

WINGS. Slightly yellowish-brown; wing venation and stigma brown.

LEGS. Integument black to dark reddish-brown. Vestiture yellowish to brownish-grey. Scopa yellowish-grey.

METASOMA. Integument black to dark reddish-brown; apical margins of terga broadly translucent yellowish to brownish (Fig. 16B). Disc of T1 and T2 very sparsely covered with very short, greyish-white, erect hair; following terga with successively more and longer, greyish-white, erect hair; apical tergal hair bands missing on all terga (Fig. 16B). Prepygidial and pygidial fimbriae dark brown. T1 and T2 impunctate, T3 and T4 with indistinct shallow punctation, looking almost impunctate; between punctures shagreened and slightly matt to shiny; apical tergal depressions very finely shagreened and slightly matt (Fig. 16B).

Male

BODY LENGTH. 8.5 mm.

HEAD. Head slightly longer than wide. Integument black, except mandible partly dark reddish-brown. Face densely covered with long, silvery-white, erect hair (Fig. 3). Malar area medially narrow, almost linear. Antenna dorsally dark brown, ventrally yellowish-brown.

MESOSOMA. Integument black. Mesoscutal disc between punctures reticulate and slightly matt; disc shallowly but densely (i =d) and relatively finely punctate. Basal area of propodeum ± triangular and distinctly carinate (Fig. 17B). Mesoscutum sparsely, scutellum and metanotum densely covered with long, yellowish, erect hair; propodeum laterally with short, apically with long, dense, yellowish, erect hair (Fig. 17B); mesepisternum sparsely covered with long, greyish, erect hair (Fig. 17A).

WINGS. Slightly yellowish-brown; wing venation and stigma brown.

LEGS. Integument black to reddish-brown, tarsi distally successively more yellowish-brown. Hind tibia apicomedially strongly swollen and curved, without distinct hair tuft (Fig. 18A). Vestiture greyish-white, on tarsi slightly yellowish.

METASOMA. Integument black to reddish-brown, apical margins of terga partly narrowly translucent dark reddish-brown (Fig. 17C). Discs of T1–T4 covered with short, greyish, erect hair, following terga with successively longer hair; apical tergal hair bands missing on all terga (Fig. 17C). Terga very finely and densely (i=d) punctate, appearing almost impunctate; between punctures and on apical tergal depressions superficially shagreened and slightly matt (Fig. 17C). S3 and S4 with dense, long apical hair fringes (laterally longer), S5 only laterally (Fig. 17D).

TERMINALIA. Genitalia (Fig. 18B), S7 (Fig. 18C) and terminal plate of S8 (Fig. 18D) as illustrated.

Distribution

Only known from the Knersvlakte (Western Cape Province) and possibly endemic to this southern-most part of the Succulent Karoo biome.

Floral hosts

Oxalidaceae: yellow flowering Oxalis spec., O. argillacea, O. purpurea .

Seasonal activity

May–June.