Arthropofauna consumed by the Andean night monkey (Aotus lemurinus) in a forest fragment at the Cordillera Central Colombia

Abstract

Arthropods are important food for primates such as night monkeys (Aotus spp.) because they provide easily digestible protein and fat.  However, the record of their consumption has been underestimated due to the opportunistic nature of their capture and difficulties in identification.  We describe arthropod consumption by a group of Andean night monkeys (Aotus lemurinus) in a fragmented forest in Colombia.  Between March and June 2016, we collected scat samples from nocturnal monitoring and visits to the resting site from a group of 4 individuals of the Andean night monkey.  We preserved the samples in 96 % alcohol and subsequently visualized them under a stereoscope.  The scats were inspected for arthropod fragments that were later determined at the taxonomic level of order and family.  In 12 of the 15 scats analyzed, we found 48 arthropod fragments, among which we classified 38 at the order level and 16 at the family level.  In total, we identified 7 arthropod orders (6 insects and 1 arachnid) and 9 insect families (5 Coleoptera, 3 Hemiptera and 1 Hymenoptera).  The orders with the highest number of fragments in the scats were Coleoptera (21), Hemiptera (5) and Orthoptera (5) and the families were Elateridae and Curculionidae with 5 and 4 numbers of fragments, respectively.  We report for the first time the consumption of the order Isoptera, as well as 2 new families of Hemiptera (i.e., Coreidae and Pentatomidae) and 5 families of Coleoptera (i.e., Chrysomelidae, Coccinellidae, Curculionidae, Elateridae and Staphylinidae) in the diet of night monkeys (Aotus spp.).  The large number of beetle fragments in the scats of Andean night monkeys could be due to the chitinous composition of their exoskeletons that makes them difficult to degrade.  This study provides novel information on the variety of arthropods consumed by the Andean night monkey and compiles all the information on the consumption of this item for the entire genus.