Cephaloleia instabilis Baly 1885

Cephaloleia instabilis es un coleóptero de la familia Chrysomelidae.

Fue descrita científicamente por primera vez en 1885 por Baly.​

Large; elongate; subparallel; subconvex; head, antennae, and scutellum black; pronotum reddish-brown with variable black markings; elytra varies from totally reddish-brown, to variable black markings, to totally black; venter variable in color; leg with protibia black, profemur reddish-yellow basally, black apically. Head: vertex and front densely punctate, medial sulcus present; frons not projecting; not depressed between eyes. Antenna: nearly ½ body length; robust; antennomeres 1–4 compressed; 1 clavate, longest of all; 2–4 triangular, subequal in length in male, 3 longer in female; 4–10 transverse, decreasing in length; 11 2× length of 10, pointed at apex; 1–3 punctate with scattered setae; 4–11 setose. Pronotum: slightly wider than long; lateral margin straight then rounding to anterior angle, slightly canaliculate; anterior angle rounded, slightly produced; posterior angle acute; anterior margin emarginate behind head; disc flattened; surface sparsely punctate; disc nearly impunctate; depressed near side; pronotal length 1.3–1.5 mm; pronotal width 1.58–2.16 mm. Scutellum: longer than wide, acutely triangular; alutaceous. Elytron: lateral margin straight, smooth, margined; apex rounded; sutural angle with tooth; humerus rounded, not produced; slightly constricted behind humerus; finely punctate-striate; declivity beginning just behind humerus along puncture row 7 with weak carina; elytral length 5.3–6.4 mm; elytral width 2.2–2.7 mm. Venter: pro-, meso-, and metasterna impunctate; abdominal sterna punctate, each puncture with pale seta; suture between sterna 1 and 2 complete; last sternite with apical margin entire, rounded in female, sinuate medially in male. Leg: slender; profemur more robust than others; metatibia punctate, others impunctate, all with fringe of setae at apex. Total length: 6.88–8.32 mm.

Costa Rica, Guatemala, Mexico, Panama.