Digitonthophagus lusinganus (d’Orbigny, 1905), d'Orbigny, 1905

Génier, François & Moretto, Philippe, 2017, Digitonthophagus Balthasar, 1959: taxonomy, systematics, and morphological phylogeny of the genus revealing an African species complex (Coleoptera: Scarabaeidae: Scarabaeinae), Zootaxa 4248 (1), pp. 1-110 : 65-67

Digitonthophagus lusinganus (d’Orbigny, 1905)

( Figs. 20 , 49–50 , 68 , 84 , 113–114, 132, 174–176; Map 15)

Onthophagus (O.) gazella var. lusinganus d’Orbigny, 1905: 495 (original description) Onthophagus (O.) gazella var. lusinganus — d’Orbigny 1913b: 249 (monograph)

Onthophagus (O.) gazella race lusinganus — Kolbe 1914: 297 (distribution)

Onthophagus gazella var. lusinganus — Gillet & Boucomont 1927: 138 (mentioned as synonym) Onthophagus lusinganus — Müller 1942: 96 (new combination, distribution)

Onthophagus (Digitonthophagus) gazella var. lusinganus — Balthasar 1963: 365 (mentioned as synonym) Onthophagus (O.) lusinganus — Ferreira 1972: 680 (catalog)

Onthophagus (Digitonthophagus) lusinganus — Kim & Lumaret, 1989: 336 (description of larvae)

Type locality. Ile de Lusinga (Victoria-Nyanza N. -E.), Afrique Orientale Anglaise [ Kenya].

Diagnosis. Male cephalic horns lacking granules internally at apex ( Fig. 50 ); males with pronotal anterior angles surface distinctly concave, simply round anteriorly ( Fig. 49 ); pronotal surface with dense, small punctures throughout ( Fig. 70 ); FLP sclerite ventral portion with a single carinae ( Fig. 176 ); SA sclerite apex interrupted much before apex of apical portion of FLP sclerite ( Figs. 174–175 ).

Description. Lectotype ♂ ( Fig. 20 ). Measurements. Length 13.5 mm, width 8.0 mm. Head ( Figs. 49–50 ). Anterior clypeal edge straight on median fifth in dorsal view; clypeofrontal carina broadly arcuate and interrupted at gena; vertex lacking median tubercle, surface with fine and minute punctures; fine punctures separated by one to three diameters. Horns rather long, arcuate, divergent in frontal view, gradually tapering from base to apex; posterointernal edge with a low, angular projection; apicointernal surface lacking granules. Punctures slightly scabrous; genal edge strongly upturned and distinctly angulate on anterior third, forming a broad angle with clypeal edge. Pronotum ( Fig. 68 ). Surface with large, weakly-defined, strongly granulate punctures restricted to anterior half medially, with smaller scattered scabrous punctures on posterior half of disc; punctures weaker but distinct posterolaterally, with dense small punctures throughout; anteromedian tubercle well developed, produced into a small, transverse, sharp ridge on each side of midline, median longitudinal sulcus deep; surface behind the eyes slightly concave, surface of anterior angles concave, anterior angles unmodified; anterior half of lateral edge arcuate in dorsal and lateral view; posterior angles simply arcuate in dorsal view. Anterior hypomeral ridge arcuate throughout, anterior hypomeral depression surface slightly darker in color medially. Elytra ( Fig. 20 ). Intervals 2 and 4 lacking fine granules from base to apical declivity. Legs. Protibial apicointernal tooth enlarged, with dorsal ridge extending to apex. Aedeagus ( Fig. 132 ). Parameres with dorsal and ventral edges diverging toward apex in lateral view. Internal sac sclerites ( Figs. 174–176 ). Axial sclerite weekly sclerotized, short, semicircular. Subaxial sclerite wide basally and abruptly narrowed at mid distance, apical half short, extending straight, interrupted before apex of frontolateral peripheral sclerite apical portion, with villi on apical half. Frontolateral peripheral sclerite basoventral apophysis well developed, forming an acute angle in lateral view; with a more-or-less rectangular medioventral carina; right lateral fold produced into a spoon-like process apically; left lateral lobe moderately sclerotized and well developed; subapicodorsal lobe membranous, small, extending in line with apex of right lateral fold, apex set on left side in dorsal view; right preapical edge entire; apex of apical lobe round apically, directed obliquely on left side, apical villi regular in shape, ventral portion with a small additional lobate projection above subapicoventral lobe; subapicoventral lobe rather small, round and interrupted before apex of apical lobe.

Variation. Measurements (64 ♂♂, 73 ♀♀). Length: male 9.5–15.0 mm (12.6 ± 1.2 mm), female 9.0–14.0 mm (12.1 ± 1.1 mm). Female paralectotype. Cephalic outline in dorsal view as in Fig. 84 ; vertex with a broadly arcuate, transverse carina, dorsal edge broadly arcuate in frontal view, lateral low and portion shortly gradually sloping down posteriorly; anterior pronotal tubercles well developed, external lateral edges rather short and slightly widening toward apex in dorsal view, anterolateral surface slightly obliquely concave, anterosuperior edge slightly arcuate in dorsal view (Fig. 113), lateral portion of anterosuperior edge slightly upturned (Fig. 114). Protibia short, with external teeth more robust.

Primary type data. Lectotype ♂ (MNHN) present designation: [AFRIQUE OR le ANGLAISE / Ile de LUSINGA / (VICTORIA-NYANZA N.-E) / CH. ALLUAUD X. 1903]; [MUSEUM PARIS / Coll. H. d’ ORBIGNY / 1913] blue card; [WORLD / SCARAB. / DATABASE / WSD00030000] barcode label; [ gazella Fabr. / v. lusinganus / var. nov . d’Orb.] handwritten on card; [LECTOTYPE ♂ / Onthophagus / gazella v. lusinganus / d’Orbigny, 1905 / dés. F. Génier, 2016] red card; [ Digitonthophagus / lusinganus ♂ / (d’Orbigny, 1905) / dét. F. Génier, 2016].

MAP 15. Distribution of Digitonthophagus lusinganus .

Material examined (91 ♂♂, 116 ♀♀), distribution (Map 15): ETHIOPIA: SOUTHERN NATIONS , NATIONALITIES, AND PEOPLE’S REGION, Arba Minch (6°2'N, 37°33'E), iv.1993, Werner— 1 ♂ ( PMOC) ; Arba Minch (6°2'N, 37°33'E), 6.ii.1978, P.-C. Rougeot— 1 ♀ ( MNHN) ; Arba Minch (6°2'N, 37°33'E), 6.ii.1978, P.-C. Rougeot— 1 ♀ ( MNHN) ; Arba Minch (6°2'N, 37°33'E), 11–17.ix.2000, P. Léonard— 19 ♀♀, 12 ♂♂ ( FGIC, PMOC) ; Lac Awassa (7°2'N, 38°28'E), 10.xi.1973, P.C. Rougeot— 1 ♀ ( MNHN) ; Nanoropus , bord du Rodolphe, 565 m (4°51'N, 36°5'E), 1932–1933, C. Arambour, P.- A. Chapuis, & R. Jeannel— 6 ♀♀, 6 ♂♂ ( FGIC, MNHN) ; Soddu [= Sodo ] (6°51'N, 37°45'30''E), 20.vii.1971, [anonymous]— 1 ♂ ( FETC) ; KENYA: Tsavo National Park [=Tsavo East National Park] (2°45'S, 38°49'E), 14.xi.1972, T.J. Kingston— 1 ♀, 1 ♂ ( OUMNH) ; Tsavo National Park [=Tsavo East National Park] (2°45'S, 38°49'E), 18.x.1973, T.J. Kingston— 8 ♀♀, 4 ♂♂ ( OUMNH) ; Tsavo National Park [=Tsavo East National Park] (2°45'S, 38°49'E), 21.xi.1973, T.J. Kingston— 4 ♀♀ ( OUMNH) ; Tsavo National Park [=Tsavo East National Park] (2°45'S, 38°49'E), 29.xi.1973, T.J. Kingston— 1 ♂ ( OUMNH) ; HOMA BAY, Baie de Kavirondo , Lac Victoria (0°31'S, 34°29'E), ix–x.1903, C. Alluaud— 1 ♂ ( MNHN) ; Ile de Lusinga [= Rusinga ], Victoria-Nyanza N. -E. (0°24'S, 34°11'E), x.1903, C. Alluaud— 12 ♀♀, 11 ♂♂ (lectotype, 22 paralectotypes) ( IRSNB, MNHN) ; ISIOLO, Isiola Samburni (0°21'23''N, 37°34'56''E), 18.xi.1975, H . A.— 1 ♀ ( BMNH) ; Meru National Park , Tana River near Post 96, 275 m (0°10'N, 38°18'E), 13.xi.1975, C.F. Dewhurst— 1 ♂ ( BMNH) ; KISUMU, 3 km SE Kisumu, 1120 m (0°9'S, 34°51'E), 17.iv.1975, Davis & Dewhurst— 1 ♀ ( MNHN) ; 6 km S Ahero , 1200 m (0°13'16''S, 34°57'24''E), 22.xi.1975, C.F. Dewhurst— 1 ♂ ( MNHN) ; Kisumu (0°6'S, 34°46'E), [no date], P.S. Corbet— 1 ♀ ( BMNH) ; MAKUENI, Kibwezi (2°24'38''S, 37°58'4''E), 20.xi.1989, P. Smerz— 1 ♂ ( JFJC) ; MERU, Leopard Rock Swamp - Post 12–33 , Meru National Park, 600 m (0°12'N, 38°14'E), 14.xi.1975, C.F. Dewhurst— 1 ♂ ( MNHN) ; NAROK, Massai Mara National Reserve (1°29'S, 35°7'E), ii.1994, Czeppel— 1 ♂ ( FETC) ; Massai Mara National Reserve (1°29'S, 35°7'E), iii.1995, Cursi— 1 ♂ ( FETC) ; RIFT VALLEY, Amboseli National Park (2°38'S, 37°14'E), 22.i.1986, R. Minetti— 2 ♀♀, 1 ♂ ( PMOC); Headquarters area , Lake Amboseli basin, Amboseli National Park , 1050 m (2°39'14''S, 37°15'22''E), 5.v.1975, Davies & Dewhurst— 1 ♀ ( BMNH) ; Talek River , Massai Mara, 1300 m (1°26'S, 35°10'E), xii.1997, P. Bleuzen— 1 ♀, 1 ♂ ( JFJC) ; SAMBURU, approximately 35 km N Wamba, Mattews Range, Rift Valley , 1300–1400 m (1°10.707'N, 37°18.962'E), 7–12.xii.2002, C. Hauser, D. Bartsch, & A. Zahm— 1 ♂ ( SMNS) ; TAITA TAVETA, Entrance Gate Tsavo National Park, Voi (3°21'47''S, 38°35'46''E), 26.xii.1990, B.D. Gill— 1 ♀ ( BDGC) ; Sagala Hills (3°29'S, 38°35'E), xii.1993, Werner— 1 ♀ (CMD) ; Taita (3°22'S, 38°22'E), [no date], [anonymous]— 2 ♀♀, 1 ♂ ( BMNH) ; Taveta (3°24'S, 37°41'E), i–iv.1904, C. Alluaud— 1 ♂ ( MNHN) ; Taveta (3°24'S, 37°41'E), iii.1912, Alluaud & Jeannel (St. 65)— 1 ♂ ( MNHN) ; Tsavo , 60 km N Voi (2°59'42''S, 38°27'41''E), 25.xii.1990, B.D. Gill— 2 ♂♂ ( BDGC) ; Voi (3°23'S, 38°34'E), xi.1997, M. Snižek— 1 ♂ ( CEMT) ; Voi (3°23'S, 38°34'E), vi/1997, O. Bužga— 1 ♂ ( PMOC) ; Voi (3°23'S, 38°34'E), 10.xii.1999, P. Smerz— 1 ♀ ( JFJC) ; Voi , Tsavo East National Park (3°23'S, 38°34'E), 31.xii.1990, B.D. Gill— 20 ♀♀, 12 ♂♂ ( BDGC) ; SOMALIA: JUBBADA HOOSE, Kismaayo, Mareri (0°21'37''S, 42°32'56''E), 29.x.1986, M. J.W. Cock— 1 ♀, 1 ♂ ( BMNH) ; SHABEELLAHA HOOSE, Genale (1°48'N, 44°42'0''E), v.1935, F. Bigi— 1 ♀ ( FETC) ; Genale (1°48'N, 44°42'0''E), [no date], [anonymous]— 1 ♀ ( NMPC) ; SOUTH SUDAN: UPPER NILE, Malakal (9°32'N, 31°39'E), 30.xi.1960, B. Hocking— 1 ♀ ( BMNH) ; SUDAN: KHARTOUM, Kawa , 157 mi. S Khartoum (13°45'N, 32°30'E), 2–3.xii.1961, J.L. Cloudsley- Thompson— 2 ♀♀, 1 ♂ ( BMNH) ; SENNAR, [unspecified locality], 1906, C. Alluaud—2 ♀♀, 2 ♂♂ (IRSNB); WHITE NIL, El Jebelain (12°35'N, 32°50'E), 3–4.xii.1961, J.L. Cloudsley-Thompson— 1 ♀ ( BMNH) ; TANZANIA: ARUSHA , Arusha environs (3°22'S, 36°41'E), 3–4.iv.1997, M. Kuboň— 5 ♀♀, 1 ♂ ( PMOC) ; Orekeryan, Mount Longido (2°43'47''S, 36°43'26''E), 8.xi.2011, R. Smith & H. Takano— 1 ♂ ( BMNH) ; DODOMA, 40 km N Dodoma, 1100 m (5°54'S, 35°45'E), 15.xii.2007, F. Kantner— 1 ♂ ( SMNS) ; Babati-Dodoma (5°15'S, 35°52'E), 6.xii.1997, Werner & Lizler— 1 ♂ (CMD) ; KILIMANDJARO, Ibaya Camp, Mkomazi Game Reserve (4°5'11''S, 38°4'55''E), 13.iv.1995, J.G. Davies— 1 ♀ ( BMNH) ; Ibaya Camp, Mkomazi Game Reserve (4°5'11''S, 38°4'55''E), 29.iii.1996, G.C. McGavin— 1 ♂ ( OUMNH) ; Same (4°4'S, 37°45'E), 12–17.v.1999, O. Bužga— 3 ♂♂ ( PMOC) ; MANYARA, Kibaone , 1348 m (3°20'11''S, 35°46'36''E), 8–10.v.2012, R. Smith & H. Takano— 1 ♂ ( BMNH) ; Mto Wa MBu , Lake Manyara National Park, 963 m (3°23'12''S, 35°52'36''E), 21.xi.2011, R. Smith & H. Takano— 14 ♀♀, 11 ♂♂ ( BMNH) ; MARA, Seronera Wildlife Lodge (2°26'50''S, 34°48'24''E), 14– 17.ii.1989, G. Bassi & Scaramozzino— 1 ♂ ( CMNC) ; MOROGO, Monts Uluguru (7°14'S, 37°33'E), 20.xi.2005, Local collectors— 1 ♀ ( PMOC); SHINYANGA , Lake Ndutu area, Serengeti National Park (2°59'S, 35°1'E), 20.i.1991, R. Foster— 1 ♀ ( OUMNH) .

Natural history. No habitat data, some specimens collected in buffalo and elephant dung. This species is attracted to mercury vapor and ultraviolet light traps.

Nomenclature and taxonomy. Digitonthophagus lusinganus was first described as a variety of Onthophagus gazella by d’Orbigny (1905). In a note on the Coleoptera of Benadir (Somalia) Müller (1942) concluded that the coexistence of two forms of “ O. gazella ” and the “ O. gazella form lusinganus ” in several East African localities was not possible and considered this form as a good species. We concur with Müller (1942) and Ferreira (1972) that this revised status is correct. The original syntype series comprises 23 specimens deposited in the Muséum national d’Histoire naturelle (Paris) and Royal Belgian Institute of Natural Sciences (Brussels). In order to stabilize nomenclature a male specimen possessing the best diagnostic characters is selected as lectotype, (present designation). This lectotype is designated in order to choose a single specimen as name bearing type in the event that the other specimens of the syntype series could belong to a different cryptic species in this genus.

Figures

FIGURES 19 – 22. Male dorsal habitus. 19. Digitonthophagus fimator, holotype; 20. D. lusinganus, lectotype; 21. D. ulcerosus, holotype; 22. D. namaquensis, holotype.

FIGURES 47 – 54. 47, 49, 51, 53. Male head, dorsal view; 48, 50, 52, 54. Male head, frontal view. 47 – 48. Digitonthophagus fimator, holotype; 49 – 50. D. lusinganus, lectotype; 51 – 52. D. ulcerosus, holotype; 53 – 54. D. namaquensis, holotype.

FIGURES 63 – 70. Male pronotum, dorsal view. 63. D. petilus, holotype; 64. Digitonthophagus viridicollis, holotype; 65. D. aksumensis, holotype; 66. D. dilatatus, holotype; 67. D. fimator, holotype; 68. D. lusinganus, lectotype; 69. D. ulcerosus, holotype 70. D. namaquensis, holotype.

FIGURES 79 – 86. Female head, dorsal view. 79. Digitonthophagus petilus, allotype; 80. D. viridicollis, allotype; 81. D. aksumensis, allotype; 82. D. dilatatus, allotype; 83. D. fimator, allotype; 84. D. lusinganus, paralectotype; 85. D. ulcerosus, allotype 86. D. namaquensis, allotype.

FIGURES 171 – 182. Internal sac sclerites (FLP, A + SA). 171, 174, 177, 180. Dorsal view; 172, 175, 178, 181. Ventral view. 173, 176, 179, 182. Right lateral view. 171 – 173. Digitonthophagus fimator, holotype; 174 – 176. D. lusinganus, lectotype; 177 – 179. D. ulcerosus, holotype; 180 – 182. D. namaquensis, holotype.

FIGURES 119 – 134. Parameres, dorsal view. 119. D. bonasus, alloreferent (Tamil Nadu State, India); 120. Digitonthophagus uks, holotype; 121. D. sahelicus, holotype; 122. D. catta, alloreferent (West Bengal, India); 123. D. eucatta, holotype; 124. D. falciger, holotype; 125. D. biflagellatus, holotype; 126. D. gazella, non type (Antisiranana Province, Madagascar); 127. D. petillus, holotype; 128. D. viridicollis, holotype; 129. D. aksumensis, holotype; 130. D. dilatatus, holotype; 131. D. fimator, holotype; 132. D. lusinganus, lectotype; 133. D. ulcerosus, holotype 134. D. namaquensis, holotype.