Compsibidion zonatum, Vlasak & Botero & Santos-Silva & -, 2025

Compsibidion zonatum sp. nov. can be included in the alternative of couplet “ 4 ” in the key from Santos -Silva et al. (2017)

4 (2). Upper eye lobes with 5 rows of ommatidia on widest area; elytra at least partially with moderately abundant,

decumbent pubescence. Bolivia......................................... C. amboroense Santos-Silva, Galileo & Wappes, 2017

— Upper eye lobes with 3 rows of ommatidia on widest area; elytra with very sparse, decumbent pubescence............ 4 ’

4 ’(4). Inner apex of upper eye lobes with three ommatidia; central macula on elytra yellowish-white; posterior area of elytra dark brown. Bolivia................................................. C. achiraense Santos-Silva, Galileo & Wappes, 2017

— Inner apex of upper eye lobes with two ommatidia; central macula on elytra yellowish brown; posterior area of elytra at least partially yellowish brown. Ecuador......................................................... C. zonatum sp. nov.

Etymology. – The name “zonatum ” (Latin, meaning banded) refers to the three color zones (brownish – yellowish – brownish) on the elytra.

Remarks. – Compsibidion zonatum sp. nov. is similar to C. achiraense Santos-Silva, Galileo & Wappes, 2017 ( Fig. 26-29; see also photographs on Bezark (2025) and in Santos-Silva et al. (2017)), but differs as follows: in females, distance between upper eye lobes wider, 0.36 times distance between outer margins of eyes ( Fig. 30, 33); in females, distance between lower eye lobes 0.5 times distance between outer margins of eyes,making frons wider ( Fig.35);longitudinalcarinae between antennaltubercles almost absentin both sexes( Fig.30, 33, 35); in females, narrowest area of mesoventral process distinctly wider than half mesocoxal width ( Fig. 31, 34); central macula on elytra yellowish-brown in both sexes; and elytra at least partially yellowish-brown posteriorly in both sexes. In the holotype female of C. achiraense (the only known specimen), the distance between the upper eye lobes is shorter, 0.3 times the distance between the outer margins of the eyes ( Fig. 26), the distance between the lower eye lobes is 0.41 times the distance between the outer margins of the eyes, making the frons narrower ( Fig.29), the longitudinal carinae between the upper eye lobes are wellmarked( Fig.29),the narrowestarea of the mesoventralprocess is as wide as half the width of the mesocoxa ( Fig. 27), central macula on elytra is yellowish white, and the elytra are entirely dark brown posteriorly.Additionally,the three specimensof Compsibidion zonatum examined have the first vertical row of the upper eye lobes with two ommatidia, while in there are three ommatidia in holotype female of C. achiraensis . However, this feature may eventually be variable. The new species is also similar to C. amboroense Santos-Silva, Galileo & Wappes, 2017 (see also photographs on Bezark (2025) and in Santos-Silva et al. (2017)), but differs especially by the elytra with more abundant, long and erect setae (very sparse in C. amboroense ), yellowish-brown macula on center of elytra reaching the suture (not reaching in C.amboroense ), inner area of the upper eye lobes narrower, with two ommatidia (wider, with three/four ommatidia in C. amboroense ), and the widest area of the upper eye lobes with three ommatidia (five in C. amboroense ).