Prey chemical discrimination and strike-induced chemosensory searching in the lizardLiolaemus zapallarensis

Summary Experimental tests were conducted to determine whether the ambush foraging iguanian lizard,Liolaemus zapallarensis, was capable of discriminating prey chemicals from control substances and whether this lizard exhibits strike-induced chemosensory searching (SICS) or its components after biting prey. The two components of SICS are a poststrike elevation in tongue-flicking rate (PETF) and apparent searching movements for relocation of prey that has been bitten, but released or escaped.Liolaemus zapallarensis failed to discriminate prey chemicals from control substances, but exhibited significant PETF lasting one minute. SICS was absent inL. zapallarensis because no post-strike movements were observed. The absence of both prey chemical discrimination and SICS exhibited byL. zapallarensis is common to all the insectivorous iguanians and ambush foraging lizards studied to date. However,L. zapallarensis is the first insectivorous iguanian species shown to exhibit PETF. The results suggest thatL. zapallarensis does not use the tongue for detection, identification, or relocation of prey while foraging. The possibility does remain thatL. zapallarensis may be capable of chemically identifying prey once the prey stimuli reach the oral cavity.