Quite an oddity: new worldwide records of <i>Renouxia</i> (Rhodogorgonales, Rhodophyta), including <i>R. marerubra</i> sp. nov.

The gelatinous, calciferous red alga <i>Renouxia antillana</i> was described in 1995 based on material from Guadeloupe, French West Indies, and accommodated in a new family and order (Rhodogorgonaceae, Rhodogorgonales) along with the genus <i>Rhodogorgon</i> from Belize and Caribbean Panama. For more than 20 years, <i>Renouxia</i> has remained monotypic, with rare reports in the Caribbean and the Indo-Pacific (from Réunion Island to French Polynesia). DNA-based analyses of recently collected <i>Renouxia</i> specimens from Egypt showed that they are not conspecific with the Caribbean <i>R. antillana</i> and are described as <i>R. marerubra</i> sp. nov. Uncorrected <i>p</i>-distances between the Red Sea specimens and the generitype were 8.0% for COI, 6.5-7.3% for <i>rbc</i>L and 3.1% for UPA. Morphological and anatomical features are also presented for the newly described species and compared to its congener, with the first documented report of monoecism in the Rhodogorgonales. Besides the new record of <i>Renouxia</i> from the Red Sea, the geographic distribution of the genus is here extended with additional records from Sri Lanka, Indonesia, as well as the islands of Guam and Kosrae in the Western Pacific. The UPA phylogeny suggests that these new distribution records may also represent undescribed species, with representatives in two distinct genetic groups.1995年，研究者基于法属西印度群岛瓜德罗普岛的标本，对胶状钙化红藻*安的列斯雷诺克斯藻（Renouxia antillana）*进行了正式描述，并将其与来自伯利兹及加勒比巴拿马的*红枝藻属（Rhodogorgon）*一同归入新设立的红枝藻科（Rhodogorgonaceae）与红枝藻目（Rhodogorgonales）。二十余年来，雷诺克斯藻属（Renouxia）始终为单型属，仅在加勒比海及印太海域（留尼汪岛至法属波利尼西亚）有零星分布报道。对近期采集自埃及的雷诺克斯藻标本开展DNA分析后发现，其与加勒比海的安的列斯雷诺克斯藻并非同种，因此将其描述为新种*红海雷诺克斯藻（R. marerubra sp. nov.）*。红海标本与该属模式标本之间的未校正p距离分别为：COI基因8.0%、rbcL基因6.5%~7.3%、UPA基因3.1%。本文还报道了该新描述物种的形态及解剖特征，并将其与同属物种进行比对，同时首次记录了红枝藻目中的雌雄同体现象。除此次红海雷诺克斯藻的新分布记录外，本文还补充了该属在斯里兰卡、印度尼西亚以及西太平洋关岛和科斯雷州的分布记录，进一步扩大了其地理分布范围。基于UPA基因的系统发育分析显示，这些新的分布记录所对应的类群可能均为尚未描述的新物种，且分属两个独立的遗传支系。