Rhyparus, Westwood, 1845

Minkina, Łukasz, Skelley, Paul, Jákl, Stanislav, Král, David & Li, Xiao-Feng, 2025, Review of the genus Rhyparus Westwood, 1845 (Coleoptera: Scarabaeidae: Aphodiinae) in the Solomon Islands with description of two new species, Zootaxa 5570 (3), pp. 563-573 : 572-573

Key to the species of the genus Rhyparus from the Solomon Islands

1. Pygidium of females distinctly bent inwards (lateral view), with last abdominal ventrite shortened medially to receive pygidium ( Fig. 4E ). Body length more than 5.9 mm. Lateral lobes of pronotum weakly developed. Caudal bulbs of eltyra lacking sinuation between median and lateral bulbs. Third intercostae of elytra with three distinct rows of medium sized punctures....................................................................................... R. malaitaensis , new species

- Pygidium and last abdominal ventrite in females normally developed. Body length more than 3.4 mm. Lateral lobes of pronotum distinctly developed. Caudal bulbs of elytra with sinuation between median and lateral bulbs more or less distinct. Third intercostae of elytra with two rows of punctures or with a third median row of much finer punctures than lateral rows...... 2

2. Larger species; body length more than 5.5 mm.Anterior lateral lobes of pronotum more prominent than median lobe. Pronotum with posterior half of median intercosta always with dense punctation. Third intercostae of elytra usually with two distinct rows of punctures, some with a third median row with much finer punctures. Caudal bulbs of elytra with sinuation between median and lateral bulbs always distinct. Meso- and metatibiae proportionally longer, distinctly longer than all tarsomeres together. Meso- and metatarsi densely pilose ventrally, surface of tarsomeres not visible................. R. breviceps Paulian, 1984

- Smaller species; body length 3.4–5.2 mm. Anterior lateral lobes of pronotum lower than posterior. Pronotum with posterior half of median intercosta with or without punctation. Third intercostae of elytra always with two rows of punctures. Caudal bulbs of elytra with sinuation between median and lateral caudal bulbs indistinct or very weakly visible. Meso- and metatibiae proportionally shorter; similar in length to all tarsomeres together. Meso- and metatarsi not densely pilose ventrally, surface of tarsomeres visible..................................................................................... 3

3. Pronotum with posterior third of median intercosta usually bearing some dense punctures. Elytral intercostae rarely with visible setae between rows of punctures. Metatibia of male ( Fig. 4C ) with inner margin swollen at basal third, then flattened or concave to apex which lacks an inner apical tooth......................................... R. helophoroides Fairmaire, 1893

- Pronotum with basal third of median intercosta lacking punctures. Elytral intercostae with macrosetae between rows of punctures. Metatibia of male ( Fig. 4B ) with inner margin regularly rounded entire length to a large inner apical tooth................................................................................ R. guadalcanalensis , new species

Figures

FIGURES 4A–G. Details of morphology. A, Rhyparus guadalcanalensis, new species, male, holotype, head; B, Rhyparus guadalcanalensis, new species, male, holotype, metatibia; C, Rhyparus helophoroides Fairmaire, 1893, male, metatibia; D, Rhyparus malaitaensis, new species, female, holotype, head; E, Rhyparus malaitaensis, new species, female, holotype, pygidium and last abdominal ventrite; F, Rhyparus argopuroensis Minkina & Jákl, 2024, female, holotype, pygidium and last abdominal ventrite; G, Rhyparus bacanensis Minkina, Anichtchenko, Vasiljeva & Skelley, 2022, female, holotype, pygidium and last abdominal ventrite.