Possible New Species of Araecerus (Coleoptera: Anthribidae) Associated with Mastixiodendron pachyclados (Garo garo), Rubiaceae

Abstract

Araecerus is a genus of beetles belonging to the family Anthribidae. They are very important economic pests of coffee, cocoa and other agricultural crops. The species that commonly attack coffee (Rubiaceae) beans is Araecerus fasciculatus (Degeer) commonly known as coffee bean weevil. However, five (5) undescribed species of genus Araecerus were reared predominantly from the seeds of Mastixiodendron pachyclados (Rubiceae) commonly known as Garo garo and it is a native tree of Papua New Guinea. Fruits of M. pachyclados were regularly sampled and insects attacking them were reared, preserved and identified. Fruits were hand collected, photographed, weighed and reared. Insects emerging from the fruits were captured and preserved in 99% ethanol. All the specimens were identified into morphospecies at the laboratory. The five new species of genus Araecerus (Anthribidae) were designated as Araecerus sp.1, Araecerus sp.2, Araecerus sp.3, Araecerus sp.4 and Araecerus sp.5 according to their differences in body length; scutellum color, size, hair-scales and visibility; length of first and second segments of fore tarsus; apical and subapical teeth-size (mandible and maxillary palpi); declivity of dorsal abdomen; basal-anterior eye markings; lateral eye markings; absence of eye markings; and shape of pygidium. Araecerus sp.1 was described as having yellowish gold marking inside the base of eye, Araecerus sp.2 with pygidium almost vertically-flat at abdominal apex, Araecerus sp.3 have eyes without yellowish gold marking and generally dark in colour, Araecerus sp.4 with distinct yellowish gold interior-lateral marking in its eye, and Araecerus sp.5 with pygidium pointed at abdominal apex. Proper identification of these five species is beneficial for effective application of control measures. Since they are major pests of cash crops such as coffee and cocoa, identification of their species and quantification of their abundance will foster economic returns and crop protection aspects as their abundance is closely related to crop damage. Keywords: Araecerus; scutellum; declivity; pygidium.