Onthophagus (sensu lato) mactatus Klug, 1855

Montanaro, Giulio, 2025, New synonymies between Afrotropical Onthophagus Latreille, 1802 (Coleoptera: Scarabaeidae: Onthophagini), Zootaxa 5647 (1), pp. 85-95 : 91-93

Onthophagus (sensu lato) mactatus Klug, 1855 valid species

( Fig. 3 )

Onthophagus mactatus Klug, 1855: 654 ; d’Orbigny, 1902: 222; d’Orbigny, 1913a: 692, 694; Ferreira, 1972: 753; Davis et al., 2020: 696.

Onthophagus talpa Fåhraeus in Boheman, 1857: 300 (new subjective synonymy); Wallengren, 1881: 21; Péringuey, 1901: 177, 226–227; d’Orbigny, 1913a: 605; Ferreira, 1958: 514; Ferreira, 1972: 756; Daniel & Génier, 2019: 28; Davis et al., 2020: 696.

Onthophagus lamelliger Gerstaecker, 1871: 52 (new subjective synonymy); Gerstaecker, 1873: 137; Quedenfeldt, 1884: 272; d’Orbigny, 1902: 218; d’Orbigny, 1905: 497, 499; Kolbe, 1908: 128; d’Orbigny, 1913a: 445, 690, 735; d’Orbigny, 1913b: 109; Ferreira, 1972: 668; Stronkhorst & Stronkhorst, 1997: 10, etc.; Daniel & Génier, 2019: 28; Davis et al., 2020: 489, etc.

Type locality: Onthophagus mactatus : Inhambane [southern Mozambique]; Onthophagus talpa : juxta fluvium Limpopo [ South Africa]; Onthophagus lamelliger : not specified in the original description, fixed here as Arusha [ Tanzania].

Type material examined. Onthophagus mactatus . Syntype, ♀: 27152 [wc, pb] // mactatus / Kl.* / Mosſamb. [wc, hb] // Hist.-Coll. ( Coleoptera ) / Nr. 27152 / Onthophagus mactatus / Klug* / Mosamb., Peters / Zool. Mus. Berlin [blue cardboard, pb] // SYNTYPE / Onthophagus / mactatus Klug, 1855 / labelled by MFNB 2024 [rc, pb] . Onthophagus talpa . Syntype, ♂: Caffra / ria. [wc, pb] // J. Wahlb [wc, pb] // Type. [wc, pb] // Talpa Fåhr [wc, hb] // Typus [rc, pb] // 75 / 68 [rc, first line pb, second line handwritten in blue] // Onthophagus talpa / FAHR. / M.C. Ferreira det.,195 [wc, first two lines hb, third line pb] // 9532 / E92 + [light blue cardboard, pb] // NHRS-JLKB / 000073787 . Onthophagus lamelliger . Syntype, ♂: 56417 [wc, pb] // lamelliger / Gerst.* ♂ / ArUscha v.d. / Dech. [light blue cardboard, hb] // SYNTYPE / Onthophagus / lamelliger / Gerstaecker, 1871 / labelled by MFNB 2024 [rc, pb].

Types repositories: ZMHB (types of O. mactatus and O. lamelliger ); NHRS (type of O. talpa ).

Diagnosis. This species belongs to d’Orbigny’s Onthophagus species-group 31 ( d’Orbigny 1913a) and falls within the dichotomy 2(7), together with O. excisiceps d’Orbigny, 1902 , O. ochropygus d’Orbigny, 1902 and O. okahandjanus Balthasar, 1974 . All these species share a carina of vertex placed between the eyes or their posterior edges, while in all remaining species of group 31 the carina is placed behind the posterior ocular edges. Details on the differences between these species can be found in Balthasar (1974) and d’Orbigny (1913a). Male genitalia ( Figs. 3e–f, 3i–j ) are also highly species-specific.

Comments. Klug (1855) described Onthophagus mactatus from Inhambane (Mozambique) , probably based on a single female, and compared it to O. sugillatus , described immediately before based on male specimens also from Inhambane.The German author excluded the possibility that the types of the two taxa were the opposite sexes of a single species by observing that O. mactatus was twice as big as the previous species, the head less deeply notched anteriorly, and the vertex carina straight instead of rounded, evenly high everywhere and “cut” laterally to eyes [ Klug, 1855: p. 654, “ Nur das Weibchen bekannt, welches doppelt so groſs wie die vorige Art ist, das Kopfschild weniger tief ausgerandet und die Scheitelleiste nicht gebogen sondern gerade, überall gleich hoch und an den Seiten vor den Augen ausgeschnitten ”]. Apparently not trusting Klug’s conclusions, d’Orbigny (1902, 1913a) suggested that the type of O. mactatus could have been just a big female of O. sugillatus . Yet, he refrained from formally proposing the synonymy, as he could not examine the type of the former species.

I have studied several specimens from Tanzania, Mozambique, Zambia and South Africa, that I confidently attribute to O. mactatus . Males are clearly different from those of O. sugillatus —which, for example, have two horns toothed proximo-medially instead of a laterally toothed carina ( Klug 1855; d’Orbigny 1913a). Instead, they perfectly correspond with the syntypes of O. talpa and O. lamelliger , which share with the O. mactatus syntype all external features (integument punctuation, colour, etc.) other than sexually dimorphic ones. Therefore, O. talpa Fåhraeus in Boheman, 1857 and O. lamelliger Gerstaecker, 1871 must be treated as junior subjective synonyms of O. mactatus Klug, 1855 .

Neither Klug (1855), nor Fåhraeus in Boheman (1857), nor Gerstaecker (1871) explicitly mentioned the number of specimens on which they based their descriptions. However, it is very likely that all three taxa were based on unique specimens, as in all descriptions there is a single body size measurement value and no documented variation, and no other specimens are known in respective collections or elsewhere. Therefore, all three specimens shall be considered as syntypes rather than holotypes (ICZN §73.2, see Rossini & Forshage (2023)).

Péringuey (1901) considered Onthophagus guttatus Boheman, 1860 also a synonym of O. talpa . However, such synonymy is incorrect (see above).

Subgeneric placement. Onthophagus mactatus has many characters of the subgenus Furconthophagus Zunino, 1979 ( Ziani 2020): the anterior hypomeral carina reaching straightly the anterolateral pronotal angles, the shape of aedeagus, the general habitus, etc. However, the lamella copulatrix is somehow divergent from the ordinary “furconthophagine” one, since it lacks three well developed branches. For this reason, for now I refrain from assigning O. mactatus to the subgenus, pending further investigations.

Etymology. The Latin adjective mactatus , literally “killed, slaughtered”, may refer to the reddish spots on the beetle’s elytra, that recall blood. Talpa is the Latin for “mole”, while lamelliger means “bearing a lamella”, probably referring to the conspicuous vertex carina of males.

Distribution. O. mactatus is a common and widespread species found, according to records of O. lamelliger , from Kenya to South Africa to Angola ( Schoolmeesters 2024).

Figures

FIGURE 3. Syntypes of Onthophagus mactatus Klug, 1855 (a–c), O. talpa Fåhraeus in Boheman, 1857 (d–g) and O. lamelliger Gerstaecker, 1871 (h–k). Onthophagus mactatus: habitus (a); genitalia (b); labels (c). Onthophagus talpa: habitus (d); aedeagus in lateral view (e); endophallus (f); labels (g). Onthophagus lamelliger: habitus (h); aedeagus in lateral view (i); endophallus (j); labels (k). Images are not to scale.