Zenker Mauricio M, Rougerie Rodolphe, Teston José A, Laguerre Michel, Pie Marcio R, Freitas André V L
Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas-SP, Brazil.
Muséum national d'Histoire Naturelle, Sorbonne Universités, Institut de Systématique, Evolution, Biodiversité (ISYEB), UMR7205 - CNRS, UPMC, EPHE, Paris, France.
PLoS One. 2016 Feb 9;11(2):e0148423. doi: 10.1371/journal.pone.0148423. eCollection 2016.
The morphological species delimitations (i.e. morphospecies) have long been the best way to avoid the taxonomic impediment and compare insect taxa biodiversity in highly diverse tropical and subtropical regions. The development of DNA barcoding, however, has shown great potential to replace (or at least complement) the morphospecies approach, with the advantage of relying on automated methods implemented in computer programs or even online rather than in often subjective morphological features. We sampled moths extensively for two years using light traps in a patch of the highly endangered Atlantic Forest of Brazil to produce a nearly complete census of arctiines (Noctuoidea: Erebidae), whose species richness was compared using different morphological and molecular approaches (DNA barcoding). A total of 1,075 barcode sequences of 286 morphospecies were analyzed. Based on the clustering method Barcode Index Number (BIN) we found a taxonomic bias of approximately 30% in our initial morphological assessment. However, a morphological reassessment revealed that the correspondence between morphospecies and molecular operational taxonomic units (MOTUs) can be up to 94% if differences in genitalia morphology are evaluated in individuals of different MOTUs originated from the same morphospecies (putative cases of cryptic species), and by recording if individuals of different genders in different morphospecies merge together in the same MOTU (putative cases of sexual dimorphism). The results of two other clustering methods (i.e. Automatic Barcode Gap Discovery and 2% threshold) were very similar to those of the BIN approach. Using empirical data we have shown that DNA barcoding performed substantially better than the morphospecies approach, based on superficial morphology, to delimit species of a highly diverse moth taxon, and thus should be used in species inventories.
形态物种界定（即形态种）长期以来一直是避免分类学障碍并比较高度多样化的热带和亚热带地区昆虫类群生物多样性的最佳方法。然而，DNA条形码技术的发展显示出巨大潜力，有望取代（或至少补充）形态种方法，其优势在于依赖计算机程序甚至在线实现的自动化方法，而非常常具有主观性的形态特征。我们在巴西极度濒危的大西洋森林的一片区域使用诱虫灯对蛾类进行了为期两年的广泛采样，以对灯蛾科（夜蛾总科：灯蛾科）进行近乎完整的普查，并使用不同的形态学和分子方法（DNA条形码技术）比较其物种丰富度。共分析了286个形态种的1075条条形码序列。基于条形码索引号（BIN）聚类方法，我们发现在最初的形态学评估中存在约30%的分类偏差。然而，形态学重新评估显示，如果对源自同一形态种（疑似隐存种情况）的不同分子操作分类单元（MOTU）个体的生殖器形态差异进行评估，并记录不同形态种的不同性别个体是否合并到同一MOTU中（疑似性二态性情况），形态种与分子操作分类单元（MOTU）之间的对应率可达94%。另外两种聚类方法（即自动条形码间隙发现法和2%阈值法）的结果与BIN方法非常相似。我们利用实证数据表明，基于表面形态学的DNA条形码技术在界定高度多样化的蛾类分类单元的物种方面比形态种方法表现出色得多，因此应将其用于物种编目。
