Scatonomus xanthopyga Pereira, 1954: 60

Valois, Marcely C., Vaz-de-Mello, Fernando Z. & Silva, Fernando A. B., 2020, A taxonomic revision of the Neotropical genus Scatonomus Erichson, 1835 (Coleoptera: Scarabaeidae: Scarabaeinae), Journal of Natural History 54 (17 - 18), pp. 1081-1114 : 1095

Scatonomus xanthopyga Pereira, 1954: 60 (sic) syn. nov.

Diagnosis

Scatonomus chalybaeus resembles S. fasciculatus and S. barbatus in having an elongated body, larger than 9 mm, and by lacking coarse and ocellate punctures on pronotum and elytra. However, S. chalybaeus is distinguished by having clypeal edge with a pair of cylindrical and short teeth, bounded by shallow lateral emarginations, not filled with a tuft of setae ( Figure 2 (b) and 3(c)).

Redescription

Male: length: 10–13 mm. Dorsum black, usually with dark blue or green reflections ( Figure 1 (c)). Head: dorsal surface transversely wrinkled, finely punctate medially ( Figure 3 (c)). Anterior edge narrowly margined. Anterior genal edge and lateral clypeal edge straight ( Figure 3 (c)). Clypeo-genal suture wide, straight, distinctly impressed. Fronto-clypeal suture ill defined between eyes. Clypeus and frons impressed medially. Inner edge of dorsal portion of eyes straight. Ventral surface of clypeus and gena filled with short setae. Each median tooth with a tubercle on ventral surface. Antennal club coated with sparse and long setae. Thorax: pronotum convex, lacking anteromedian impressions or knobs. Disc shiny, slightly wrinkled and finely punctate. Mid- longitudinal sulcus of pronotum inconspicuous. Transverse carina of hypomera incomplete, not reaching the lateral edge. Surface of mesepimeron and mesanepisternum black, finely striate. Elytra: s triae thin, shallow, indistinctly punctate; striae on disc at least 10 times narrower than the third interstria. Lateral edge of striae finely carinate. Seventh stria absent at the basal one-seventh of elytra. Eighth stria present only at apical two-thirds. Ninth stria present at the apical half of elytra. Interstriae almost flat, shiny and finely punctate. Legs [ventral surface]: profemora punctate on anterior half; posterior half with setose punctures and microgranulation throughout. Outer edge of protibia with 3 acute teeth, basal tooth smaller than median and apical teeth. Mesofemur and metafemur finely punctate. Outer edge of mesotibia with row of erect setae and small teeth. Abdomen: abdominal ventrites II–VI with row of small tubercles along posterior edge. Ventrite V as long as VI. Pygidium: 1/3 wider than long, disc shiny, with well-defined microgranulation. Genital capsule: paramera apex divided into apical and lateral lobes by shallow V-shaped emargination. Apical lobe rounded. Lateral lobe truncate, slightly wider than long ( Figure 5 (b)). Female: differs from male in abdominal ventrites II–VI smooth along posterior edge. Ventrite V slightly convex medially, with half length of ventrite VI. Pygidial disc shiny, sparsely punctate.

Figures

Figure 1. Dorsal habitus. (a) S Scatonomus barbatus stat. rev.; (b) S. canhedoae sp. nov.; (holotype); (c) S. chalybaeus; (d) S. fasciculatus; (e) S. foresti sp. nov. (holotype); (f) S. insignis; (g) S. janssensi; (h) S. mitzae sp. nov. (holotype); (i) S. paulosawayai (holotype); (j, k) S. thalassinus; (l) S. viridis.

Figure 2. Terminology used to describe the head parts. (a) Scatonomus canhedoae sp. nov.; (b) S. chalybaeus.

Figure 3. Head, dorsal view. (a) Scatonomus barbatus stat. rev.; (b) S. canhedoae sp. nov. (holotype); (c) S. chalybaeus; (d) S. fasciculatus; (e) S. foresti sp. nov. (holotype); (f) S. insignis; (g) S. janssensi; (h) S. mitzae sp. nov. (holotype); (i) S. paulosawayai (holotype); (j, k) S. thalassinus; (l) S. viridis.

Figure 5. Aedeagus, detail of right paramera and endophallic sclerites. (a) Scatonomus barbatus stat. rev.; (b) S. chalybaeus; (c) S. fasciculatus; (d) S. foresti sp. nov.; (e) S. insignis; (f) S. janssensi; (g) S. mitzae sp. nov.; (h) S. thalassinus; (i) S. viridis; (j) endophallic sclerites of S. fasciculatus.