Introduction

The proper identification of insect pests, and their associated natural enemies, is an important component in developing a holistic system for managing rice insect pests. To help national rice research programs in 17 West African countries identify specimens in their rice insect collections, a comprehensive collection program began during the period 1990-1995 to establish a rice insect and natural enemy collection at WARDA, the Africa Rice Center.

Most of the insects and spiders were collected in upland, rainfed-lowland, irrigated-lowland, hydromorphic and slash-and-burn agroecosystems in Cote d’Ivoire and neighboring West African countries. Most of the collections were conducted in Cote d’Ivoire and at the WARDA M’be Rice Research Station, near Bouake.

In 1994 and 1995, my research assistant, Traore Abdoul Kassoum Aboubacar, and I hand carried the WARDA collection to the International Rice Research Institute. There, over a period of nine years, IRRI insect and arachnid taxonomist, Dr Alberto Barrion, identified the specimens and produced an illustrated key based on that collection. The key was richly illustrated by IRRI Department of Entomology staff, Cris dela Cruz and Jessamyn R. Adorado. The key was entitled An Illustrated Key to the Identification of Selected West African Rice Insects and Spiders and was published (pp. 99-222) in the book, Rice Feeding Insects and Selected Natural Enemies in West Africa (2002). Authored by E. A. Heinrichs and Alberto Barrion, this book was edited by IRRI Director of Communications, G. P. Hettel, and jointly published by the International Rice Research Institute and WARDA.

This is the only key that includes all the major insect orders and selected spiders in the West African rice ecosystem. The key to orders consists of ten insect orders: Lepidoptera, Diptera, Odonata, Dermaptera, Strepsiptera, Orthoptera, Mantodea, Coleoptera, Hemiptera and Hymenoptera, and the spider order, Araneae. The keys include both rice pests and their natural enemies. The illustrations are based on adult specimens. Three other keys of economically important rice insects in West Africa- stem borers, leafhoppers and planthoppers and gall midges are availabl e: Meijerman and Ulenberg (1996) made an excellent contribution to the identification of African stem borer larvae from the families Pyralidae and Noctuidae, while Wilson and Claridge (1991) dealt with leafhoppers and planthoppers, and Harris and Gagne (1982) studied the gall midges. Polaszek (1992) treated the parasitoids of cereal stem borers, including the rice stem borers.

As the published book is now out-of-print, the insect and spider keys are no longer available in a published, hard-copy version. However, a recent upgrade of the software product, the Lucid Builder, for constructing interactive Matrix keys, now includes a program for building dichotomous or pathway keys, as well as providing a facility to convert existing, paper-based dichotomous keys to interactive, online keys. Using this software, all the keys published in the 2004 book have now been converted to digital keys and made freely available online, courtesy of the International Association for the Plant Protection Sciences (IAPPS). You can access the keys at https://keys.lucidcentral.org/keys/v4/west_african_rice_insects_and_spiders/

Apart from their value for rice plant protection specialists, these online, illustrated, rice insect and spider keys also provide useful training tools for parataxonomists (high school and college graduates without formal training in entomology and taxonomy). The interactive nature of this Lucid edition of the key makes it more user friendly than the book version. This is especially the case with thumbnail and enlarged images available, for the 275 insect species and 69 spider species associated with West African rice agroecosystems. A brief introduction to each of the insect groups and arachnids, and an explanation of scientific terms (glossary) provide further assistance in describing the species in each of the Orders.

The insects and spiders included in the key have been deposited in the IRRI Global Rice Arthropod collection. While some species of insects and natural enemies found in West African rice are not included in the collection, the major and most economically important species are included. As a result, we hope that the key will be useful in identifying and understanding the components of the arthropod communities in West African rice agroecosystems, and lead to the development of effective pest management systems.

E. A. Heinrichs
January 1, 2022
Lincoln, Nebraska