Scarabaeus (Pachysoma) rodriguesi (Ferreira, 1953)

Harrison, J. Du G., Scholtz, C. H. & Chown, S. L., 2003, A revision of the endemic south-western African dung beetle subgenus Scarabaeus (Pachysoma) MacLeay, including notes on other flightless Scarabaeini (Scarabaeidae: Scarabaeinae), Journal of Natural History 37 (3), pp. 305-355 : 340-341

Scarabaeus (Pachysoma) rodriguesi (Ferreira, 1953)

( figures 12 , 29 , 47, 68)

Neopachysoma rodriguesi Ferreira, 1953a: 44 ; Ferreira, 1961: 25; Ferreira, 1966: 60; Ferreira, 1969: 25; Zunino, 1977: 15. Holotype: Namtib, Namibia (1 3 TMSA).

Pachysoma rodriguesi (Ferreira) : Holm and Scholtz, 1979: 237.

Scarabaeus rodriguesi (Ferreira) : Mostert and Holm, 1982: 275.

Diagnosis. Head with prominent tubercle on frons ( figure 29 ); protibia sexually dimorphic, spurs strongly bifid ( figure 47a, b); posterior pronotal margins with sharp points on either side; large, shiny and reddish black in colour; metatarsal claws long; male genitalia illustrated in figure 68a, b.

Distribution, habitat and conservation. Restricted to the central Namib dune area ( figure 12 ). Their morphology reflects adaptation to ultrapsammophilous conditions of the central dune sea. S. (P.) rodriguesi is contained within the Namib-Naukluft Park.

Comments on locality data. Holm and Scholtz (1979) mentioned the curious record along the Buffels River. They noted that the single female collected did not differ significantly from the northern population, except in having the tubercle on the frons reduced. The size of the tubercle on the frons varies within and between sexes from the same population and thus does not constitute a population specific character. Recent extensive field work along the Buffels River yielded no S. (P.) rodriguesi and confirms the suspicion by Holm and Scholtz (1979) that this specimen is incorrectly labelled.

Morphological variation. The size of the protuberance on the frons varies in both the 13 females and in the 11 males in the material of S. (P.) rodriguesi from 20 miles south of Gobabeb .

Biology. Holm (1970) and Holm and Scholtz (1979), give detailed accounts of the biology of S. (P.) rodriguesi . To summarize, the species collects Oryx and hare pellets that are dragged forward to their preconstructed burrows, but no use of detritus is mentioned. S. (P.) rodriguesi has been observed mating above ground in the afternoon ( Holm and Scholtz, 1979). The larvae are unknown.

Comments. S. (P.) rodriguesi is an unmistakable large central Namib species, with only very large specimens of S. (P.) hippocrates and S. (P.) glentoni matching it in size.

Types. Ferreira (1953a) described Pachysoma rodriguesi from five specimens, four of which she deposited in the TMSA collection and one paratype in the CPMM collection. All the types are currently in the TMSA collection. The date is omitted from the printed locality labels, while the holotype has a separate label with the date (26 September 1953) on it. Ferreira (1953a) records the date of collection of the type series as 26 September 1950. Considering the description of P. rodriguesi was published in 1953, we suspect the date of collection was the 26 September 1950, rather than 26 September 1953 as recorded on the holotype.

Type material examined (S5 specs [5], 1 ♀ 4 3, 3 3 diss.). NAMIBIA: HOLOTYPE 3, Neopachysoma rodriguesi Ferreira : Namtib, 70m NW of Aus, (ca. 25.58S 16.02E), Gt. Namaquald., C.Koch, G.van Son / 26.ix.1953 (written in pencil on faded white paper) / Holotipo Neopachysoma Rodriguesi M.Cornita Ferreira, 1950 (written in red ink on white card, with a black border around the label) / Holotypus Neopachysoma rodriguesi M.C.Ferreira sp.n. (written by Endrödy-Younga on TMSA Ferreira label), (1 3 TMSA); (aedeagus of the holotype is point mounted on a separate pin, but labelled idem); ALLOTYPE ♀, idem, but Alotipo (sic) Neopachysoma Rodriguesi M.Cornita Ferreira, 1950 (written in red ink on white card, with a black border around the label) / Allotypus Neopachysoma rodriguesi M.C.Ferreira sp.n. (written by Endrödy-Younga on TMSA Ferreira label), (1 ♀ TMSA). PARATYPES: idem, but Paratipo (sic) Neopachysoma Rodriguesi M.Cornita Ferreira, 1950 (written in red ink on white card, with a black border around the label) / Paratypus Neopachysoma rodriguesi M.C.Ferreira sp.n. (written by Endrödy-Younga on TMSA Ferreira label), (3 3 TMSA).

Additional material examined from Namibia (S93 specs [37], 44 ♀ 49 3, 3 3 diss) .

Figures

FIGS 10–13. Distribution of Scarabaeus (Pachysoma) species in Namibia. Questioned locality records or range extensions are shown by an open circle. (10) S. (P.) fitzsimonsi. (11) S. (P.) rotundigenus. (12) S. (P.) rodriguesi. (13) S. (P.) denticollis.

FIGS 18–35. (18–30) Head of Scarabaeus (Pachysoma) species in dorsal view: (18) S. (P.) aesculapius. (19) S. (P.) hippocrates. (20) S. (P.) glentoni. (21) S. (P.) endroedyi. (22) S. (P.) striatus. (23) S. (P.) gapiepinus. (24) S. (P.) bennigseni. (25) S. (P.) schinzi: (a) female, (b) male. (26) S. (P.) valeflorae: (a) female, (b) male. (27) S. (P.) fitzsimonsi. (28) S. (P.) rotundigenus. (29) S. (P.) rodriguesi. (30) S. (P.) denticollis. (31, 32) Head of flightless Scarabaeus (Scarabaeolus) species in dorsal view. (31) S. (Scarabaeolus) scholtzi. (32) S. (Scarabaeolus) silenus. (33–35) Head of flightless Scarabaeus (Scarabaeus) species in dorsal view. (33) S. (Scarabaeus) ritchiei. (34) S. (Scarabaeus) sevoistra. (35) S. (Scarabaeus) cancer.