Search

Some species of CyclocephalaDejean, 1821 (Coleoptera, Scarabaeidae, Dynastinae, Cyclocephalini) were reported as crop or pasture pests. Within this genus, Cyclocephla tucumanaBréthes, 1904 was noticed in cultivated areas in South Brazil, 2009 − 2010. Other study found larvae of the species associated with pastures in Aquidauana, Mato Grasso do Sul State (MS), 2009. In the present study, larvae of C. tucumanawere collected in pasture areas from August 2015 to July 2016, in Cassilândia, MS. The material was reared in laboratory for the description of immatures, and the regional population was studied to clarify its dynamics. Immatures were abundant throughout the years and are described for the first time. Taxonomic discussion, updated key to larvae and pupae, and a teratological note are also added.

Mating behavior and description of immature stages of Cyclocephala melanocephala(Fabricius, 1775) (Coleoptera: Scarabaeidae: Dynastinae), identification key and remarks on known immatures of Cyclocephalini species. Some species of CyclocephalaDejean, 1821 are regarded as rhizophagous crop pests and others as beneficial species. The objective of this work was to report the mating behavior and to describe the immature stages of C. melanocephala. The studies were developed at the Universidade Estadual de Mato Grosso do Sulin Cassilândia, Mato Grosso do Sul state, Brazil. Adults were collected with a light trap from September to December 2014 and 2015 to carry out studies of mating behavior, breeding, and descriptions of immature stages. Copulation lasted 10.4±4.3min and took place from 19:00 to 24:00h. Some females refused males for mating and moved away from them. Regarding flight period, adults were collected in larger quantities from 20:00 to 23:00h. Identification keys to immatures of three genera of Cyclocephalini, including several Cyclocephalaspecies are presented.

Description of immatures and mating behavior of Liogenys bidenticepsMoser, 1919 (Coleoptera: Melolonthidae: Melolonthinae). Some species of Melolonthinae are associated with several species of cropped plants, with larvae consuming roots and, in some cases, are considered as crop pests. In some agricultural regions of Brazil, larvae of L. bidenticepsare found associated with cultivated plants, and little information is available about this taxon. This study, aiming at expanding the knowledge about the morphology and behavior of this species, provides the description of immatures and mating behavior of adults. The studies were conducted at the experimental farm of the Universidade Estadual de Mato Grosso do Sulin Aquidauana, Mato Grosso do Sul state, Brazil, and the adults were collected with light trap and raised in the laboratory. Mating behavior was documented on video both in the field and under laboratory conditions. Descriptions and illustrations of the third instar larva and pupa are presented. Adults have crepuscular flight activity and their copulation lasts an average of 20.25min, occurring from 19:00 to 22:00h. On some occasions, females did not accept males for copulation, indicating an active selection of males by females. Field observations demonstrated that adults feed on Brazilian pepper leaves (Schinus terebinthifolius, Anacardiaceae) and cashew flowers (Anacardium occidentale, Anacardiaceae), where male and female meet each other and copulation occurs.

Liogenys fuscais a rizophagous insect pest in various crops of economic importance in Brazil. Here we investigated the morphology of immature stages and mating behavior of this species. The redescription of the 3rd instar larvae of L. fuscain this work allows identification and registration of occurrence independently of adults, which occur sporadically in a certain period of the year. Male and female of L. fuscaremained confined in the soil during the day and exited between 19:00 and 23:30h. The copulations occurred between 19:30 and 21:00h, and were characterized by a typical behavioral sequence. Copulation durations in L. fuscalasted on average 512.23s. Adults were observed feeding before the copulations on leaves and inflorescences of plant species belonging to the family Anacardiaceae, Myracrodruon urundeuva, Schinus terebinthifolius, Astronium fraxinifoliumand Anacardium occidentale.