INTRODUCTION

The family Formicidae, i.e., ants, is one of the dominant invertebrate taxa in both natural and man-made ecosystems of warmer-climate zones, and affects the ecosystems as predator of small animals, scavenger, seed eater, seed disperser, soil-mixing agent, prey of small animals, etc. Furthermore activities of ants undoubtedly affect productivities in agroecosystems. Recent inventory works on local ant fauna in North Vietnam (Bui 2002; Yamane et al. 2003; Bui & Eguchi 2003; Eguchi et al., 2005) show high species richness of ants in the country. For example, a total of 160 species belonging to 50 genera are recorded only from Cuc Phuong National Park, a lowland limestone forest (Yamane et al. 2003). Vietnam, which is located in the easternmost part of Indo-Chinese Peninsula, is a latitudinally long country. Lowlands widely spread in the North (the basin of the Hong River) and in the South, while mountain areas spread over the border of Vietnam with China and of Vietnam with Laos. Da Lat Plateau approaches the coastal line of Southern Central Vietnam, and thus the southern lowland is somewhat separated from the northern lowland. Monsoon climate in Vietnam can be subdivided into six types based on temperature, rainfall and their seasonality (Nguyen et al. 2000). Such complexity of topology and climate undoubtedly maintains an extremely high diversity of ants. It is no wonder that the total number of ant species in Vietnam is over 500.

Taxonomy (descriptive taxonomy) of Vietnamese ants was initiated by Europian and American in the early of 20th century, and approximate 160 ant taxa were described or recorded in the period (Bingham, 1903; Santschi 1920a, b, 1924; Wheeler 1927, 1928; Karawajew 1935). The identity of these taxa needs to be revised based on the modern taxonomy of ants. From 1965 to 1966 an inventory project of insects in the northern Vietnam was conducted by the Agriculture Ministry of Vietnam, and 36 ant species were recorded (National Institute of Plant Protection 1976). Since the end of 1980's dozens of ant species has been newly recorded or described from Vietnam (e.g., Radchenko 1993a, 1993b, Radchenko & Elmes 2001; Roncin 2002; Dubovikoff 2004; Eguchi & Bui 2005, 2006; Eguchi 2006). However, those covered only a part of Vietnamese ant fauna or certain taxa. Modern taxonomic monograph giving an overview of the fauna has not yet been published. It is not too much to say that taxonomy of ants in Vietnam still remain in an initial stages.

How can we develop the taxonomic capacity in myrmecology in Vietnam? The Myrmecological Society of Japan set a good example. Since the society established in 1965 upon M. Kubota's initiative many amateurs and professionals have conducted faunal, taxonomic and ecological studies of Japanese ants. In the process common names (Japanese names) have been given to the almost all ant species known from Japan (the Japanese Society of Myrmecology (ed.) 1988). Because the type material of the majority of Japanese ants were stored in western museums, and taxonomic literature on ants was hardly obtained in Japan, Japanese myrmecologists faced difficulties to know the scientific names of Japanese ants (even species commonly found) until the last several decades. Thus, common names allowed us to accumulate and compile information on Japanese ants. Upon those results, identification guides and distribution map of Japanese ants at the species level were published (the Japanese Society of Myrmecology (ed.) 1989, 1991, 1992; Terayama & Kihara 1994). In recent years the identity of Japanese ant species has been confirmed by referring to modern taxonomic literature and the type materials. Then "Japanese Ant Color Image Database" was set up on the web in 1995. It was revised in 2003 as "Ant Image Database (Japan)": http://ant.edb.miyakyo-u.ac.jp/), and "Ants of Japan" was published (Japanese ant database group 2003).

In order to develop the taxonomic capacity in myrmecology in Vietnam, we plan to propel the following actions.

 1) Exploring local ant faunas
Steady inventory works for local faunas provide us basic and indispensable information for conducting biodiversity conservation. Thus we should continuously explore local ant faunas especially in the central highland and the southern part of Vietnam where we have not yet intensively conducted ant surveys.

2) Giving species codes to all species
Instead of the common name system adopted in Japan a species code system should be established for accumulating and compiling taxonomic and other biological information from various sources. Then our recognition of species mainly based on worker morphology should be verified with various kinds of biological information (because we accepted the biological species concept).

3) Overviewing ant genera known from Vietnam
Identification tools for Vietnamese ants will make contributions to research projects and conservation programs concerning biodiversity in natural and man-made environments of Vietnam. Specimens and various kinds of biological information provided by such projects and programs are valuable for developing the taxonomic capacity further. And development of taxonomic capacity may promote further research projects and conservation programs... It is a great positive feedback. Therefore, this CD book should be a milestone of myrmecology in Vietnam.

4) Describing unnamed taxa and reviewing higher taxa known from Vietnam and adjacent areas
Species codes should be, of course, replaced by scientific names, and unnamed species should be named in the course of future studies. We would like to promote an ambitious but steady plan: by the end of the first half of 21st century 70% of Vietnamese ants will be named. It may be widely accepted that "70%" is the minimum point of "the success".

© Katsuyuki EGUCHI & BUI Tuan Viet, 2007. All rights reserved.