Phoberus fumarius

Phoberus fumarius (Haaf, 1953), revalidated and new combination

(Figs 8–14, 16, 21)

Trox fumarius Haaf, 1953: 334 (original description); Haaf 1959: 473 (checklist, localities); Scholtz 1980a: 97 (new junior synonym of Trox (Trox) cyrtus); Scholtz 1982: 3 (catalogue, as synonym of Trox (Trox) cyrtus); Zidek 2013: 9, 10 (checklist, as synonym of Trox (Phoberus) cyrtus); Zídek 2017: 99, 101 (checklist, as synonym of Phoberus cyrtus).

Type locality. Willowmore (Sarah Baartman District Municipality, Eastern Cape Province, South Africa)

Type material examined. HOLOTYPE Ƌ (NHMB, aedeagus extracted, examined through detailed photographs) (Figs 8–10): Rectangle, greyish white: “[South Africa, Eastern Cape Province] Willowmore [33°17′S 23°29′E] | 30.10.[19]48.” || Rectangle, white: “Süd-Afrika | leg. C. Koch” || Rectangle, white: “Museum Frey | Tutzing” || Rectangle, white with red bars at top and bottom, preprinted red text interspersed with black handwriting: “HOLOTYPUS | Trox | fumarius sp.n. | det.Dr.E. HAAF 1953 ” || Rectangle, white, preprinted black text interspersed with black handwriting: “ Trox fumarius | Haaf (= Trox | cyrtus Haaf. | det. C.H. SCHOLTZ 1979” || Rectangle, white cardstock with black margin: “ Phoberus fumarius | (Haaf, 1953) | stat. rev., comb. nov. | Strümpher & Stals 2021”. PARATYPE 1Ƌ (TMSA, aedeagus extracted): Rectangle, yellowing white: “Willowmore, | Capland. | Dr. H. Brauns.” || Narrow rectangle, red: “ PARATYPE ” || Rectangle, white, preprinted text interspersed with handwriting: “ Trox | fumarius Haaf | det.Dr.E. Haaf 1953 ” || Rectangle, white cardstock with orange margin: “ Paratypus 1953 | Trox fumarius sp.n | E. Haaf” || Rectangle, white cardstock with black margin: “ Phoberus fumarius | (Haaf, 1953) | stat. rev., comb. nov. | Strümpher & Stals 2021”.

Haaf (1953) described Trox fumarius from three males and one female, deposited in NHMB (among these we studied the male holotype); one male in the Hungarian Natural History Museum, Budapest (not seen by us); and one male and one female in TMSA, of which we studied the male paratype but could not locate the female.

Additional material examined. SOUTH AFRICA. Northern Cape Province. 1♁ Richtersveld, Paradieskloof [recte Paradyskloof], 28°19′S 17°00′E, 06.ix.2001, E-Y:3412, light trap, TMSA staff (TMSA). 1♀ idem but E- Y:3413, on vegetation [sic] (TMSA). 2♀ Richtersveld, Gelykswerf [Mountain], [c. 28°22′S 17°08′E], x.1955, C Koch (TMSA). 1♁ Namaqualand, Swart Doring River, [30°48′S 17°54′E], 02–03.x.1966, S.A.M. [South African Museum] (TMSA). 1♁ Namaqualand, Dermbergsdraai Farm, 30°47′S 17°43′E, pitfall traps: 24.viii.1979 – 26.x.1979, E-Y:1589, S Endrödy-Younga (TMSA). 1♁ Kamieskroon, 30°12′S 17°56′E, 01–13.ix.2003, A Frolov, C Deschodt (UPSA, preserved in 99% ethanol). 1♀ Namaqualand, Garies, [30°33′30″S 17°59′E], vi.1930, Museum staff (SAMC: SAM-COL-A082505). Western Cape Province. 1♁, 1♀ Farm Zeekoeivlei [recte Seekoevlei], near Clanwilliam, [32°09′S 18°45′E], 27.xi.2003, farm staff (TMSA). 1♁ Saldanha Bay, Jutten Island, [33°05′0.5″S 17°57′19″E], 25.i.[19]51, Swedish South African Expedition, 1950–1951, P Brink, G Rudebeck (MZLU: MZLU-COL00007061, through photographs). 1♁, 4♀ Cape Town, 65 km N, 33°21′S 18°15′E, pitfall traps: 30.viii.1983 – 01.xi.1983, E- Y:1999, S Endrödy-Younga, M-L Penrith (TMSA). 20 unsexed: Dassen Island, 33°25′24″S 18°05′14″E, 18.ix.2009, WP Strümpher, CH Scholtz (UPSA, preserved in 99% ethanol); 6♁, 3♀ idem but dry-mounted (SANC); 1♁ idem but dry-mounted (SAMC: SAM-COL-A082509). 2♁ Citrusdal, [32°35′S 19°01′E], v.1974, Honiball (TMSA). 1♀ Cape Town, [33°55′S 18°25′E], 1913 (TMSA). 1♁ CPT [Cape Town], Green Point, [33°54′25″S 18°24′23″E], 16.vi.1958, JA Nagle (TMSA). 2♁ Cape-Karoo, Farm Zwartskraal, 33°10′S 22°32′E, pitfall traps: 08.xi.1978 – 17.i.1979, E- Y:1540, S Endrödy-Younga (TMSA); 1♁ idem but 01.ii.1979 – 02.iii.1979, E-Y:1545, R Oosthuizen (TMSA); 1♁ idem but 02.iii.1979 – 31.iii.1979, E-Y:1552, R Oosthuizen (TMSA); 1♁ idem but 23.vii.1979 – 05.ix.1979, E- Y:1637, R Oosthuizen (TMSA); 1♁ idem but 05.ix.1979 – 25.x.1979, E-Y:1639, R. Oosthuizen (TMSA); 1♁ idem but 25.x.1979 – 09.xii.1979, E-Y:1672, R. Oosthuizen (TMSA); 1♁ idem but 01.i.1980 – 18.ii.1980, E-Y:1699, R Oosthuizen (TMSA); 1♁ idem but 22.ix.1980 – 08.xi.1980, E-Y:1717 (TMSA). 1♀ Touws R [iver], [33°20′15″S 20°02′E], 1896, Purcell (SAMC: SAM-COL-A082507). 1♁, 2♀ Zwartberg Pass [recte Swartberg Pass], [33°21′S 22°03′E], Prince Albert district, xii.1968, RH Jones, JH Potgieter (TMSA); 1♁, 1♀ idem (SAMC: SAM-COL- A082508, SAM-COL-A082510). 1♀ Swartberge [Swartberg Mountains], Blesberg East, 2,000 m, 23°25′S [recte 33°25′S] 22°41′E, pitfall traps: 16.xii.1976 – 02.iii.1977, E-Y:1532, S Endrödy-Younga (TMSA). 1♀ Gamkaberg Nature Reserve, [33°43′S 21°54′E], ii–iii.1994, T Berry (TMSA). 1♁ Riversdale, [34°02′45″S 21°15′45″E], RJ Power (TMSA) (Figs 11–14); 2♁, 1♀ idem (SAMC: SAM-COL-A082503–A082505).

Redescription. Size: Length: 13–14 mm. Width across humeri: 6–8 mm.

Colour (Figs 8, 11–12): Matt black. Body setae yellow-brown (amber) to light rust-brown.

Head (Figs 11–12): As in Phoberus cyrtus, except surface coarsely sculpted and densely punctate, surfaces between punctures smooth, dull matt; antennal scape with long yellowish-brown to rust-brown setae.

Pronotum (Figs 11–12, 16): As in Phoberus cyrtus, except surface coarsely punctate; punctures prominent, round; surfaces between punctures smooth, dull matt.

Scutellum (Figs 11–12): Oval, rounded; surface smooth; lateral margins flat; mediobasally depressed, depression punctate.

Elytra (Figs 8, 11–12): Relative dimensions, margins and profiles as in Phoberus cyrtus. Humeral calli as in Phoberus cyrtus. Sutural margin raised, surface smooth, with distinct round to oval tubercles regularly distributed along margin, roughly of similar size for 0.75 elytral length, thereafter decreasing in size until barely discernible; these tubercles as in Phoberus cyrtus. Elytral costae distinct; even-numbered costae with prominently raised oval to elongate tubercles, roughly of equal size and height, evenly spaced along elytral length; these tubercles smooth, dull, each with a posterior setal tuft. Apical callosity as in Phoberus cyrtus. Elytral costae 2 and 4 with 8–12 tubercles for 0.75 elytral length (up to apical callosity); odd-numbered costae marked by small round to oval, dull shiny tubercles like in Phoberus cyrtus, but these tubercles closely spaced. Costae 1–8 separated from intercostae as well-defined elevated bands. Intercostae with undulating depressions separated by transverse ridges, the margins of intercostae 1–7 marked by distinct, narrow longitudinal ridges, thereafter intercostae with carinae vestigial, barely discernible or lacking.

Legs (Figs 11–12): As in Phoberus cyrtus.

Metathoracic wings: Complete.

Male genitalia (Figs 9, 13): Symmetrical, slender, phallobase arched, as long as parameres. Parameres long, extending beyond median lobe, apices pointed and curved. Median lobe divided into two symmetrical parts, these broad, not parallel, with distinct basolateral swelling, in dorsal view concave upward; apices angularly rounded and incurved; two bladelike projections and hooks visible between parameres and median lobe.

Diagnosis. Phoberus fumarius and Phoberus cyrtus are very similar to each other. The two species can be told apart as elaborated under the diagnosis of Phoberus cyrtus, above. Whereas both species can be confused with the common and widespread Phoberus sulcatus, Phoberus fumarius is more likely to cause such confusion. Again see the discussion under Phoberus cyrtus, above.

Geographic distribution. Phoberus fumarius is presently known only from the Northern Cape and Western Cape Provinces of South Africa, apart from its type locality that marginally falls in the westernmost Eastern Cape Province. The known distribution of the species follows the Cape Fold Mountains, along the western mountain chain from the Richtersveld southwards through Namaqualand to the West Coast Peninsula and the Cape Peninsula; and from there eastwards along the southern mountain chains as far east as the town of Willowmore (Fig. 21). This is a distribution pattern that broadly repeats among many beetle species and higher categories. Another example from the Trogidae is the Phoberus capensis species-group (Strümpher et al. 2016a).

The distribution of this species may well reach further east into the eastern Cape Floristic Region; and it may well extend into southern Namibia, since it is known from the Richtersveld on the southern side of the Gariep River, while identical habitat is present on the northern side of the river in Namibia (Fig. 21). Phoberus fumarius is present on off-shore islands on the Western Cape Atlantic coast. Two of these ‘guano islands’ are noted above; Haaf (1959) additionally reported this beetle species from Malgas Island (33°03′10″S 17°55′31″E) in Saldanha Bay.

Broad habitat associations. The known distribution of Phoberus fumarius is confined to the Greater Cape Floristic Region of Born et al. (2007), falling entirely in the winter rainfall region of southern Africa, whereas the range of the putative sister species Phoberus cyrtus is confined to the summer rainfall region. Phoberus fumarius has been recorded at an altitude of 2,000 m above sea level in the Swartberg Mountains and close to sea level on the West Coast and the Cape Peninsula. No field-collected information about habitat associations exists for this species, and the possible vegetation types in which it occurs are geographically complexly arranged, necessitating caution when inferring where the species lives.

The distribution of Phoberus fumarius is in the northwest centred on the Succulent Karoo Biome (Richtersveld to Namaqualand) and on the Fynbos Biome in the south and towards the east (biomes, bioregions and vegetation units sensu Mucina & Rutherford 2006; Dayaram et al. 2019). In the Fynbos Biome the species may likely occur in both Fynbos and Renosterveld vegetation units, but dedicated collecting is required to confirm or refute this. At higher altitudes along the southern mountains the species may again be found in Succulent Karoo habitats, and specifically in the Rainshadow Valley Karoo Bioregion. In the Swartberg and Little Karoo it possibly occurs in intrusions of the Albany Thicket Biome. On the off-shore islands the species occurs in Western Strandveld, a vegetation unit of the Fynbos Biome.