The larval stages of the variegated mud-loving beetle Heterocerus similis Grouvelle (Coleoptera: Heteroceridae)

Abstract

Last instar larvae of the variegated mud-loving beetle Heterocerus similis Grouvelle are described and illustrated in detail. Comparative notes with earlier instars are also included. Based on the width of the head capsule and the prothorax four different instars were identified; considering that heterocerids show five larval instars, the four instars identified probably correspond to the last four. Larval length was not useful to recognize among different larval stages. The larva of H. similis is compared to that of H. freudei (Pacheco), the only other described South American heterocerid larva.Se describen e ilustran en detalle las larvas del último estadio del escarabajo ripario Heterocerus similis Grouvelle y se incluyen notas comparativas con los estadios anteriores. Sobre la base del ancho de la cápsula cefálica y del protórax se lograron identificar cuatro estadios larvales; considerando que los heterocéridos presentan cinco estadios larvales, los estadios identificados probablemente correspondan a los últimos cuatro. El largo de las larvas no permite distinguir entre estadios. La larva de H. similis se compara con la larva de H. freudei (Pacheco), la única otra larva de heterocérido sudamericana descripta.