Antennal sensilla of the primary larva of the false firefly beetle Drilus mauritanicus Lucas, 1849 (Coleoptera, Elateridae, Agrypninae, Drilini) Les sensilles antennaires de la larve de Drilus mauritanicus Lucas, 1849 (Coleoptera, Elateridae, Agrypninae, Drilini)

Antenna of the primary larva and associated sensilla of a common malacophagous beetle in Morocco, Drilus mauritanicus Lucas, 1849 (Elateridae, Agrypninae, Drilini) are compared to other coleopteran larvae in order to discover whether these structures were influenced by malacophagy. The number of sensilla on the larval antenna of D. mauritanicus of the last instar larvae is 26 sensilla: 12 aporous sensilla chaetica C1, 3 uniporous sensilla chaetica C2, 1 long aporous sensillum chaeticum C3; 1 sensillum campaniformium; 1 sensillum styloconicum; 8 sensilla basiconica including 1 very large multiporous sensillum basiconicum B1 and 7 small sensilla basiconica B2-B8. The total number of sensilla is greater than that of most other species. The larval antenna is an important olfactive organ; which enables it to seek out its prey thanks to the large multiporous sensillum basiconicum B1, much more developed in D. mauritanicus than in the other coleopteran larvae, and also thanks to certain other sensilla basiconica. It is also a gustatory organ (sensilla chaetica type 2, sensilla basiconica B6) which is used during the bite of the prey and perhaps also during ingurgitation of the partly liquified flesh of the snail. The long terminal sensillum chaeticum C3 can be considered as a sensillum filiformium sensitive to air currents; it is replaced in other coleopteran larvae by 1 or several shorter gustatory sensilla.