Scrapter carysomus, Davies, 2005

Kuhlmann, Michael, 2025, New species and species group in the bee genus Scrapter Lepeletier & Serville, 1828 (Hymenoptera: Colletidae) oligolectic on Oxalis flowers in western South Africa, European Journal of Taxonomy 987, pp. 146-188 : 178-181

publication ID	https://doi.org/10.5852/ejt.2025.987.2863
publication LSID	lsid:zoobank.org:pub:9D9B200A-8887-4E52-8D0C-A6B78D1B8B0F
DOI	https://doi.org/10.5281/zenodo.15425208
persistent identifier	https://treatment.plazi.org/id/7D38FB0F-FFF1-8D29-FF09-2073D044FA74
treatment provided by	Plazi
scientific name	Scrapter carysomus
status

Treatment

Key to species of the Scrapter carysomus View in CoL group

Females

Females of this species group are very similar to each other and identification can be difficult without reference material or associated males due to sometimes very subtle differences in the surface sculpture.

1. Fore tibia on inner face medially, on outer face apically, and fore femur on outer face apically with dull yellow spot of varying size ........................................................................... S. oxalicus sp. nov.

– Foreleg blackish-brown, sometimes femur apically slightly dark yellowish-brown ........................ 2

2. Propodeum dorsolaterally (lateral to the matt propodeal triangle) partly smooth and shiny ( Figs 23A– B View Fig ); disc of T2 relatively coarsely and densely punctate (i=0.5–2 d) ( Fig. 24A–B View Fig ) ......................... 3

– Propodeum dorsolaterally (lateral to matt propodeal triangle) very finely shagreened and matt (e.g., Fig. 23C–D View Fig ); disc of T2 finely, more dispersed punctate (i> 2d) or without punctation (e.g., Fig. 24C–D View Fig ) ...................................................................................................................................... 4

3. Clypeus, vertex and dorsal side of mesosoma with white to light brown hair, at most few single black hairs intermixed; basal area of propodeum without rugae ( Fig. 23A View Fig ); T2 distinctly and densely (i=0.5–1d) punctate ( Fig. 24A View Fig ) ..................................................................... S. oxaliphilus sp. nov.

– Clypeus, vertex and dorsal side of mesosoma with abundant dark brown to blackish hairs intermixed with lighter hair; basal area of propodeum on anterior half with fine longitudinal rugae ( Fig. 23B View Fig ); T2 comparatively more shallowly and sparsely (i=2 d) punctate ( Fig. 24B View Fig ) ..................................... ......................................................................................................................... S. oxalissimus sp. nov.

4. Apical tergal depressions relatively broad, yellowish translucent with the adjacent apical area of the disc crescent-shaped dark reddish ( Fig. 24C View Fig ) .......................................... S. carysomus Davies, 2005 View in CoL

– Apical tergal depressions narrower and brownish translucent without reddish discoloration of the adjacent apical area of the disc ( Fig. 24E–F View Fig ), if apical tergal depressions yellowish translucent, then only very narrowly ( Fig. 24D View Fig ) .......................................................................................................... 5

5. Scutellum slightly smaller (shorter and narrower), more convex and shinier ( Fig. 23E View Fig ); hair on posterior surface of propodeum shorter than length of basal area of propodeum ( Fig. 23E View Fig ) ............. .................................................................................................................................. S. oxalis sp. nov.

– Scutellum slightly larger (longer and broader), flatter and duller ( Fig. 23D–F View Fig ); hair on posterior surface of propodeum longer than length of basal area of propodeum ( Fig. 23D–F View Fig ) ...................... 6

Separation of the following two species is very difficult:

6. Apical tergal depressions slightly broader ( Fig. 24D View Fig ); basal area of propodeum with slightly sparser and coarser reticulation ( Fig. 23D View Fig ) ..................................................................... S. oxalensis sp. nov.

– Apical tergal depressions slightly narrower ( Fig. 24F View Fig ); basal area of propodeum with slightly denser and finer reticulation ( Fig. 23F View Fig ) ......................................................................... S. oxaloides sp. nov.

Males

The male of S. oxaloides sp. nov. is unknown.

1. Foreleg with medio- and distitarsi completely bright yellow, basitarsus and tibia predominantly yellow ............................................................................................................................................... 2

– Foreleg completely dark brown to blackish, sometimes to small extent distitarsus and apical parts of mediotarsi orange-brown .................................................................................................................. 3

2. Tarsi of mid and hind leg completely bright yellow; hind tibia apically on inner side with hairs longer ( Fig. 25A View Fig ); genitalia as in Fig. 26A View Fig .......................................................... S. oxalicus sp. nov.

– Tarsi of mid and hind leg predominantly dark yellowish-brown to blackish; hind tibia apically on inner side with hairs shorter ( Fig. 25B View Fig ); genitalia as in Fig. 26B View Fig ............ S. carysomus Davies, 2005 View in CoL

3. Hind tibia apicomedially strongly swollen ( Figs 9A View Fig , 18A View Fig ); propodeum densely covered with thick, plumose hair of ± equal length ( Figs 27A–B View Fig , 28A, C View Fig ) ..................................................................... 4

– Hind tibia apicomedially not conspicuously swollen ( Fig. 25E–F View Fig ); propodeum sparsely covered with thin hair of variable length ( Fig. 27C–D View Fig ) ................................................................................. 5

4. S3–S5 with dense apical hair fringes ( Fig. 28D View Fig ); hind tibia apicomedially more strongly swollen, hairs on inner side in apical half comparatively short ( Fig. 25D View Fig ); genitalia as in Fig. 26C View Fig ............... .................................................................................................................................. S. oxalis sp. nov.

– S3–S5 with sparse apical hair fringes ( Fig. 28B View Fig ); hind tibia apicomedially less swollen, hairs on inner side in apical half comparatively long ( Fig. 25C View Fig ); genitalia as in Fig. 26D View Fig ....... S. oxalensis sp. nov.

5. Clypeus medially finely and sparsely punctate, shiny; basal area of propodeum without or anteriorly only with very short, indistinct longitudinal carinae ( Fig. 27C View Fig ); genitalia as in Fig. 26E View Fig ................. ......................................................................................................................... S. oxaliphilus sp. nov.

– Clypeus medially coarsely and denser punctate, matt; basal area of propodeum with distinct longitudinal carinae that extend over the majority of the length of the segment ( Fig. 27D View Fig ); genitalia as in Fig. 26F View Fig .................................................................................................. S. oxalissimus sp. nov.