Data from: Taxonomic quality of species descriptions varies over time and with the number of authors, but unevenly among parasitic taxa

While concerns are being raised about a potential shortage of taxonomists and systematists, recent analyses suggest instead that the number of researchers involved in taxonomic descriptions is higher than ever and that the average number of new species described annually per taxonomist has declined in recent decades. Here, using nine metrics of taxonomic quality, such as the number of morphological traits measured, the number of separate line drawings included, and whether or not gene sequences are provided, we explore variation in taxonomic quality as a function of the number of authors and other potential determinants across 2366 descriptions of parasitic helminths published in 1337 articles between 1980 and 2014. Taxonomic quality has generally increased over time, but unequally among different groups of helminths. For example, the number of scanning electron micrographs per description has risen significantly over time in cestodes and nematodes, but decreased for digeneans. For most metrics used, the greater the number of authors per species description, the higher its quality, suggesting not more taxonomists but more collaborations between taxonomists and experts from other fields to produce more comprehensive species characterisations. Re-descriptions of species were of higher quality than their original descriptions, and the improved quality correlated with the number of years elapsed between them; However, the extent of this improvement varied among helminth species with different host taxa. Overall, our findings provide a note of caution for anyone using trends in the number of species described per author to extrapolate the total number of extant species. They also reveal cultural differences among taxonomists working on different groups of parasites that can serve to identify areas for potential improvement.

尽管学界对分类学家（taxonomists）与系统学家（systematists）的潜在短缺存在担忧，但近期的分析结果却表明，参与分类学描述（taxonomic descriptions）的研究人员数量实则较以往任何时期都更高，且近数十年来，每位分类学家年均新增物种描述量的平均值有所下降。本研究采用9项分类学质量评价指标，涵盖所测量的形态性状数量、纳入的独立线条绘图幅数，以及是否提供基因序列（gene sequences），对1980年至2014年间发表于1337篇学术论文中的2366篇寄生蠕虫（parasitic helminths）分类学描述展开分析，探究分类学质量随作者数量及其他潜在影响因素的变化规律。整体来看，分类学质量随时间推移总体呈上升趋势，但在不同蠕虫类群间的提升幅度并不均衡。例如，绦虫纲（cestodes）与线虫纲（nematodes）的每份分类描述所附扫描电子显微镜照片（scanning electron micrographs）数量随时间显著增加，而复殖吸虫纲（digeneans）的该指标则呈下降趋势。就本次研究采用的多数评价指标而言，单份物种描述的作者数量越多，其分类学质量越高，这意味着推动分类学家与其他领域专家开展更多合作，而非单纯增加分类学家人数，才能实现更全面的物种性状表征。物种重描述的分类学质量高于其初始描述，且质量提升幅度与两次描述的间隔年数呈正相关；不过，这一提升程度因宿主类群不同的蠕虫物种而异。总体而言，本研究结果对那些试图通过单作者年均描述物种数量的趋势来推断现存物种总数量的研究者发出了警示。同时，本研究还揭示了针对不同寄生虫类群的分类学家之间存在的文化差异，这些差异可作为识别潜在改进方向的依据。