Tenuis leaf-beetle (Euliroetis tenuis), brick red leaf-beetle (Euliroetis testacea) and Euliroetis simulonigrinota syn. nov

NEWS - Two new species were described: tenuis leaf-beetle (Euliroetis tenuis sp. nov.) and brick red leaf-beetle (Euliroetis testacea sp. nov.), five species were redescribed and a new synonym was proposed: Euliroetis nigrinota Gressitt et kimoto, 1963 = Euliroetis simulonigrinota Yang 1992 syn. nov. based on examination of type specimens and morphology of male and female genitalia.

Euliroetis was established by ogloblin (1936) for Aenidea ornata Baly 1874. Five species: E. abdominalis (Baly, 1874), E. lameyi (Laboissière, 1929), E. nigripes (Baly, 1874), E. ornata (Baly, 1874) and E. suturalis (Laboissière, 1929) were originally described in Aenidea Baly 1874, Liroetis Weise 1887 and Phyllobrotica Chevrolat 1836.

The Nanling Mountains are an important mountain range and watershed in southern China on the border of Hunan Province, Jiangxi, Guangdong and Guangxi Zhuang Autonomous Region. These mountains stretch for about 600 km from east to west and about 200 km from north to south.

When researchers studied leaf beetles from the Nanling Mountains, two species were identified: E. ornata (Baly, 1874) and a new species: E. tenuis. When revising all Chinese Euliroetis species, they found another new species E. testacea sp. nov. and proposed a new synonym: E. nigrinota Gressitt et kimoto, 1963 = E. simulonigrinota Yang 1992, syn. Nov.

E. tenuis has a distribution in Guangdong, Guangxi (China). Very similar to E. ornata in elytra spots, but differs in that the elytra are brown and black at the apex, abdominal ventrite 1 with a pair of elongated protrusions in the middle instead of triangular protrusions. Aedeagus with a deep bifurcation at the apex and curved towards the middle.

Also very similar to E. testacea, but differs in that antenomere 3 is about 1.3× longer than antenomere 2, and ventrite 1 has a pair of slender, elongate, backward-pointing processes.

Male length 4.5–4.7 mm, width 2.4–2.5 mm. antennae black brown with antennomeres 1–4 reddish brown. head, pronotum, and scutellum reddish brown, ventral surface of body brown. Elytra brown with apex black, each elytron with two yellow spots.

Femur and tibia externally reddish brown internally brown, tarsus and claw reddish brown. head smooth, impunctate. antennae slender, 0.8× as long as body; antennomere 2 shortest, antennomere 3 approximately 1.3× as long as antennomeres 2, antennomere 4 slightly longer than antennomere 3, antennomeres 5–11 equal in length.

Pronotum 1.3× as wide as long, disc sparsely covered with small punctures, with transverse furrow in middle. Scutellum triangular, with a rounded apex, smooth, and impunctate. Elytra wider than pronotum, 0.75× as long as body, 2.2× as long as wide, dorsal surface covered with deep punctures, interstices of punctures slightly wider than diameter of punctures.

Abdominal ventrite 1 with a pair of slender protrusions at center, elongate and directed backwards, ventrites 2–5 with a deep medial concavity, ventrite 2 with 2 broad protrusions strongly extending to posterior covering ventrite 3; ventrites 3–5 lateral portions strongly curved to center; pygidium deflexed posteriorly. Aedeagus widest in middle, gradually narrowed towards base; apex bifurcated, and curved towards middle; distinctly bent in lateral view.

Female length 4.8–5.2 mm, width 2.5–2.8 mm. Abdominal ventrites 1–5 without modification and concavity. Spermatheca with a widened nodulus, middle part slightly narrowed, cornu narrowed and curved, spermathecal duct slender and slightly curved at base. Vaginal palps wide at base, anteriorly with subtriangular tip, each palp slightly narrowing posteriorly, with a rounded apex, 5 setae placed at apex, additional 2 setae subapically.

E. testacea has a distribution in Guangxi (China) and the epithet refers to the brick red color of the antennae. Similar to E. tenuis, but antenomere 3 is about 1.65× longer than antenomere 2 and abdominal ventrite 1 with a pair of triangular processes, but ventrite 2 is wider. While E. tenuis has antenomer 3 about 1.3× longer than antenomer 2, ventrite 1 with a pair of slender, elongated and backward-pointing protrusions.

Also very similar to E. melanocephala in terms of elytra color, but E. testacea differs in antennae brownish black; antenomeres 1–3 reddish brown, elytra apex black, abdominal ventrite 1 with a pair of prominent curved hooks in the middle and a strongly hooked aedeagus in the middle.

Male length 4.7 mm, width 2.5 mm. antennae brick red with antennomeres 1–3 reddish brown. head, pronotum, scutellum, and leg reddish brown, ventral surface of body brown, elytra brown with apical part of sutural margin and apex black. head smooth, and impunctate.

Antennae slender, 0.8× as long as body; antennomere 2 shortest, antennomere 3 approximately 1.65× as long as antennomeres 2, antennomere 4 slightly longer than antennomere 3, antennomeres 5–11 equal in length. Pronotum 1.4× as wide as long, disc sparsely covered with small punctures, with transverse furrow in middle.

Scutellum semicircular, with rounded apex, smooth, and impunctate. Elytra wider than pronotum, 0.7× as long as body, 2.3× as long as wide, dorsal surface covered with deep punctures, and interstices of punctures slightly wider than diameter of punctures.

Abdominal ventrite 1 with a pair of triangular protrusions and directed towards each other, extending to posterior; ventrites 2–5 with a deep medial concavity, lateral portions strongly curved to center; pygidium deflexed posteriorly, protrusions on ventrite 2 longer than ventrites 3–5. Aedeagus widest in middle, gradually narrowed towards base; apex bifurcated, and curved towards middle; strongly bent in lateral view.

Original research

Chuan Feng, Zheng-Zhong Huang, Xing-Ke Yang & Si-Qin Ge (2024). Revision of Euliroetis Ogloblin, 1936 (Coleoptera: Chrysomelidae: Galerucinae) from China, with descriptions of two new species. Zootaxa 5528 (1): 758-771, DOI:10.11646/zootaxa.5528.1.51

Dlium theDlium