Rhyparus breviceps Paulian, 1984

Skelley, Paul E. & Minkina, Łukasz, 2025, Review of the Rhyparini (Coleoptera: Scarabaeidae: Aphodiinae) of eastern Melanesia and Polynesia, with descriptions of new species, Zootaxa 5632 (1), pp. 115-137 : 127-128

Rhyparus breviceps Paulian, 1984

Figures 28–29

Rhyparus breviceps Paulian, 1984: 472–474 , fig. 1. Type locality: “ Papua New Guinea, Morobe, umg. Kaiapit”. Stebnicka 1998: 847 (redescription).

Diagnosis. A member of the genus Rhyparus , distinguished by the length 7.0– 7.9 mm ( Fig. 28 ). Pronotum with triangularly prominent anterior and intermediate lobes; prominent pronotal carina; median intercostal punctation coarse. Elytral intercostae smooth; first elytral intercostal with two rows of punctures; large trichome on caudal bulb ( Fig. 29 ); caudal bulb with lobes triangularly rounded. Abdominal ventrites 2–4 not (or weakly) crenate anteriorly with triangular fovea on each side. Mesotarsus and metatarsus with ventral surface densely pilose, obscuring surface.

Distribution. New Guinea ( Stebnicka 1998), Solomon Islands ( Minkina et al. 2025), and American Samoa.

Material examined (3 total). Holotype deposited in MHNG from Papua New Guinea and the following from the study region: American Samoa: Tuitula, Fagatoga, 10.I.1964, N.R. Spencer (2 BPBM, 1 FSCA).

Comments. While similar to R. rugatus in many ways, R. breviceps is easily distinguished from other regional species by the obtuse clypeal tooth on each side of anterior margin, distinct lateral lobes on pronotum, smooth elytral intercostae; and large elytral trichome. See comments under R. rugatus .

The presence of R. breviceps on American Samoa represents a very distant and potentially isolated population for this group of Rhyparus . However, these specimens are not distinguishable from R. breviceps , falling within a range of variation seen in materials from New Guinea and the Solomons. For now, they are considered R. breviceps , as there is a possibility the species may have recently migrated to the islands. See comments under R. helophoroides .

Figures

FIGURES 28–33. Rhyparus species. 28) Rhyparus breviceps Paulian, female from Papua New Guinea, dorsal habitus; 29) Rhyparus breviceps Paulian, female from Papua New Guinea, elytral apex, oblique-caudal view; 30) Rhyparus fijiensis Minkina, Anichtchenko, Vasiljeva, & Skelley, dorsal habitus male paratype; 31) Rhyparus fijiensis Minkina, Anichtchenko, Vasiljeva, & Skelley, abdominal ventrites female paratype; 32) Rhyparus helophoroides Fairmaire, male from New Caledonia, dorsal habitus; 33) Rhyparus helophoroides Fairmaire, male from New Caledonia, abdominal ventrites, ventral-oblique view. Scale lines = 1.0 mm.