Rossi Natalia, Magalhães Célio, Mesquita Elis R, Mantelatto Fernando L
Laboratory of Bioecology and Crustacean Systematics (LBSC), Faculty of Philosophy, Sciences and Letters at Ribeirão Preto (FFCLRP), University of São Paulo (USP), Av. Bandeirantes 3900, 14040-901, Ribeirão Preto, São Paulo, Brazil..
Zootaxa. 2020 Feb 11;4732(1):zootaxa.4732.1.9. doi: 10.11646/zootaxa.4732.1.9.
A freshwater palaemonid shrimp from the São Francisco river basin in Brazil has been found to be a new species and is herein nominated as Macrobrachium veredensis sp. nov. It is morphologically similar to M. brasiliense (Heller, 1862), which is found in many rivers of South America. However, M. veredensis sp. nov. has a smooth carapace and few spinules on the second pereopods, while M. brasiliense has the anterolateral surface of the carapace with small spinules and the palm of the second pereopods with spines, spinules and setae. Despite their similar morphology with these subtle differences, the remarkable genetic different evidenced in DNA analysis. Molecular analyses were based on 43 sequences with 528 base pairs (bp) for 16S rDNA, and 16 new sequences with 581bp, without pseudogenes, for COI mtDNA. The nucleotide divergence between M. veredensis sp. nov. and M. brasiliense (7.0-8.5% for 16S and 11.8-12.5% for COI.), the phylogenetic topology and the haplotype network configuration and it is endemism to a region of the São Francisco river basin support the recognition of a new taxon.
在巴西圣弗朗西斯科河流域发现了一种淡水长臂虾，它是一个新物种，在此被命名为维氏沼虾（Macrobrachium veredensis sp. nov.）。它在形态上与巴西沼虾（Macrobrachium brasiliense，Heller，1862）相似，后者分布于南美洲的许多河流中。然而，维氏沼虾的头胸甲光滑，第二对步足上有少量小刺，而巴西沼虾的头胸甲前侧表面有小刺，第二对步足的掌节有刺、小刺和刚毛。尽管它们形态相似但存在这些细微差异，DNA分析显示出显著的遗传差异。分子分析基于43条16S rDNA序列（528个碱基对）和16条新的COI线粒体DNA序列（581个碱基对，无假基因）。维氏沼虾和巴西沼虾之间的核苷酸差异（16S为7.0 - 8.5%，COI为11.8 - 12.5%）、系统发育拓扑结构以及单倍型网络构型，再加上它是圣弗朗西斯科河流域一个区域的特有物种，这些都支持将其认定为一个新分类单元。
