Mordellidae (Coleoptera) Research: A Review Based on the Zoological Record from 1864 through 2013

Mordellidae (tumbling flower beetles) is a globally distributed family of Coleoptera; it is among the most species-rich families (containing 115 genera and 2308 species described). It is important because of its agroforestry significance and its ecosystem-sustaining attributes. However, the past and current status of Mordellidae research remains unclear. A comprehensive literature review of Mordellidae articles published over the period of 1864⁻2013 based on the Zoological Record was conducted for the first time. A total of 863 articles were used for analysis after a strict literature search using screening protocols. These articles were then assigned to four categories based on the year of publication, topics/themes, primary authors, and frequently utilized journals for publication of Mordellidae-related articles. The results reveal that: (1) there are three prosperous research periods (1876⁻1898, 1922⁻1957, and 1977⁻2012) for Mordellidae during 1864⁻2013 that are associated with the active period of three generations of the main taxonomists. However, it is unfortunate that it also demonstrates there is a lack of upcoming researchers to continue the work after the retirement of the current generation, thus action should be taken immediately to promote research on Mordellidae; (2) on average, each primary author published 3.1 papers, but ~35% of the Mordellidae articles were published by less than 3% of the primary authors; (3) researchers tended to mostly publish their articles in local journals of their home countries; (4) more than 90% of the articles pertain to traditional taxonomy, with those of early times generally containing only simple descriptions of the species and the holotypes chosen are sparsely deposited with the researchers or amateurs around the world, thus making them difficult to be checked; (5) nearly half of the studies described Mordellidae species from Palaearctic realm, about one-third of the studies described species in other areas rather than in the fauna in which the authors lived, and about two-fifths of the studies described species from countries outside of the authors' country of origin. Therefore, the in-depth systematic study of worldwide Mordellidae is required to reconstruct Mordellidae phylogeny and a revision of its classification system with modern methods of comparative morphology, molecular biology, zoogeography, and cladistics. In order to better understand the life stages and biology of Mordellidae insects, more work on Mordellidae ecology should be undertaken to develop strategies for pest control. We hope that this review will provide information to the novice and expert alike in Mordellidae research pertaining to its past and current status, possible future research areas, and attract more attention from the scientific world and renew an interest in Mordellidae research.