Reis Vinícius J C, Dos Santos Sergio A, Britto Marcelo R, de Assis Volpi Thaís, de Pinna Mário C C
Museu de Zoologia da Universidade de São Paulo, 481 Av. Nazaré, São Paulo, São Paulo, 04263-000, Brazil.
Institut de Systématique, Evolution, Biodiversité, Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles CP 30, Paris, France.
J Fish Biol. 2020 Dec;97(6):1607-1623. doi: 10.1111/jfb.14490. Epub 2020 Oct 6.
This paper reports on a new species of Trichomycterus from the Rio Doce basin. Unusually for new taxa in the genus during the past few decades, the new species is not narrowly endemic but instead widely distributed in its major drainage, the Rio Doce. The species has been collected and deposited in scientific collections for some years, but has been systematically misidentified as the more abundant Trichomycterus immaculatus or, to a lesser degree, as other morphologically similar species from south-eastern Brazil such as T. nigricans and T. pradensis. A combination of several morphological characteristics, such as vertebral number, pectoral-fin ray counts, pigmentation pattern and barcoding distance, were iteratively used and unambiguously distinguish the new species from all congeners. The present case reveals a pattern of diversity-discovery in which rare and narrowly endemic morphologically conspicuous species are discovered and described before visually inconspicuous taxa, even when the latter are more abundant and widespread. The morphological similarities among south-eastern Brazilian species with a uniform dark-grey color serve as basis for a brief discussion about the concepts of cryptic and pseudo-cryptic species in Trichomycterus and their consequences for potentially hidden diversity in the genus.
本文报道了一种来自多西河盆地的新的三毛鲶属物种。在过去几十年里，该属新分类群的情况不同寻常，新物种并非狭域特有，而是广泛分布于其主要流域——多西河。该物种已被采集并保存在科学标本馆数年，但一直被系统地误鉴定为更为常见的无斑三毛鲶，或者在较小程度上被误鉴定为来自巴西东南部的其他形态相似的物种，如黑三毛鲶和普拉德三毛鲶。通过反复使用多种形态特征的组合，如脊椎骨数量、胸鳍鳍条数、色素沉着模式和条形码距离，明确地将新物种与所有同属物种区分开来。本案例揭示了一种多样性发现模式，即形态显著的稀有和狭域特有物种在形态不显眼的分类群之前被发现和描述，即使后者更为常见和广泛分布。巴西东南部颜色均一深灰色的物种之间的形态相似性，为简要讨论三毛鲶属中隐存物种和拟隐存物种的概念及其对该属潜在隐藏多样性的影响提供了依据。
