关于墨西哥淡水鱼的新闻

创建者 Juan Miguel Artigas Azas (10-6月-2026)

一项发表在 Nature 上的新研究探讨了亚马孙摩利鱼 Poecilia formosa 如何在克隆繁殖的情况下延续了超过 100,000 年。该论文由 Edward S. Ricemeyer、Nathan K. Schaefer、Manfred Schartl 和 Wesley C. Warren 等人主导，研究了进化生物学中的一个长期谜题：为什么一个不进行有性繁殖的物种没有出现理论所预测的基因组衰退？

Poecilia formosa 是一种全雌性、具有杂交起源的鱼，源自 Poecilia mexicana 和 Poecilia latipinna 之间的一次古老杂交。由于它产生的女儿本质上是母亲的遗传复制品，它缺少有性繁殖通常带来的基因重组。这种重组通常帮助自然选择清除有害突变，并传播有用突变。

利用高质量的基因组组装，研究人员将亚马孙摩利鱼基因组中的两个祖先来源部分分离出来，并将它们与其有性亲缘物种的基因组进行比较。他们发现，克隆基因组确实比有性物种的基因组更快地积累了变化。然而令人惊讶的是，这并没有导致预期中的遗传衰退。

关键似乎在于基因转换，这是一种类似 DNA 修复的过程，其中一个遗传副本可以覆盖另一个副本。在 Poecilia formosa 中，基因转换似乎有助于清除有害突变、保存有用变异，并减少由其杂交起源带来的问题。

这项研究并不是说有性繁殖在进化中不重要。相反，它表明某些克隆动物可能拥有意想不到的基因组工具，使自然选择能够继续发挥作用。对于水族爱好者和自然爱好者来说，亚马孙摩利鱼不只是一个生物学奇观：它是一个活生生的提醒，说明进化常常会在水族箱过滤器里藏着一个备用小妙招.

Ricemeyer, Edward S & Nathan K. Schaefer, Kang Du, Irene da Cruz, Susanne Kneitz, Rafael D. Acemel, Darío G. Lupiáñez, Rachel A. Carroll, Rosie Drinkwater, Manfred Schartl, Wesley C. Warren. 2026. "Gene conversion empowers natural selection in a clonal fish species". Nature. (652):398–404 - [摘要] · (ffm01333)

创建者 Juan Miguel Artigas Azas (14-8月-2025)

一种新的淡水年鱼——Profundulus hectori，在墨西哥东南部的梅斯卡拉帕河上游流域及特万特佩克地峡的河流中被描述。该发现发表在期刊《Neotropical Ichthyology》上，增加了人们对中美洲淡水生物多样性的认识，并凸显了该地区的生态重要性与脆弱性。

该研究的作者均来自墨西哥，他们结合了形态学特征和遗传数据，确认了该物种的独特性。随着这一新增，Profundulus 属现已包括 12 个有效物种，全部为中美洲特有。

Profundulus hectori 的特征是体侧鳞片上具有一组大型黑斑，其中许多至少达到眼径的一半。这一特征将其与该属所有其他已知物种区分开来。它还表现出沿侧线和背鳍前方具有更多的鳞片数。

基于线粒体 DNA 的遗传分析显示，与其他 Profundulus 物种相比，其差异至少为 3.86%，支持其作为独立物种的认定。系统发育结果将 P. hectori 定位为 P. chimalapensis 的姐妹种，并与 P. punctatus 和 P. oaxacae 组成一支。

种加词 hectori 用以纪念已故的墨西哥著名鱼类学家、墨西哥国立自治大学生物学院的 Héctor Espinosa Pérez 博士。作者们肯定了 Espinosa 博士在墨西哥淡水鱼研究上的杰出贡献，以及他对新一代研究者的指导。

目前，该物种已知仅分布于恰帕斯东部梅斯卡拉帕河及邻近流域的少数地点。这些河流通常清澈、凉爽，水流适中至湍急，底质为砾石和岩石。尽管部分栖息地仍保持良好状态，但其他一些面临污染、栖息地改造和人类活动的威胁。

Domínguez-Cisneros, Sara Elizabeth & Ernesto Velázquez-Velázquez, Omar Domínguez-Domínguez, Rosa Gabriela Beltrán-López. 2025. "A new species of Profundulus (Cyprinodontiformes: Profundulidae) from southeastern Mexico". Neotropical Ichthyology. 23(2): - [摘要] · (ffm01319)

创建者 Juan Miguel Artigas Azas (30-7月-2025)

After being lost to science for nearly 90 years, the rare killifish Cynodonichthys myersi has been rediscovered in the mangroves of northern Yucatán. Originally described in 1936, it was later thought to be the same species as C. tenuis, but new research confirms it’s a distinct species. DNA analysis shows that C. myersi is actually more closely related to species found far away in Panama than to its Mexican neighbors, suggesting a surprising and separate evolutionary path. With its unique coloration—males have blue-green hues with dark spots and females have speckled tails—and a possible ability to survive briefly out of water, this rediscovered fish adds a fascinating twist to the story of Central American freshwater biodiversity.

Dominguez-Castanedo, Omar & Stefano Valdesalici, Waldir M. Berbel-Filho, Liliana García-Calva, Sharon Valdez-Carbajal. 2025. "Rediscovery and redescription of Cynodonichthys myersi from the mangroves of northern Yucatan Peninsula, Mexico (Cyprinodontiformes, Rivulidae)". Journal of Fish Biology. 1–11 - [摘要] · (ffm01307)

创建者 Juan Miguel Artigas Azas (25-10月-2021)

A new species of killifish in the genus Profundulus has been described in the journal Ichthyology & Herpetology 109(4):949–957 2021 by Sara E Dominguez-Cisneros, Ernesto Velázquez-Velázquez, Caleb D. McMahan, and Wilfredo A. Matamoros.

The new species significantly extends the known distribution of Profundulus in the Atlantic slope of Mexico to the upper reaches of the Papaloapan drainage in Oaxaca [México], from which Profundulus until now wasn’t known. The new species has been given the name Profundulus adani, to honor the Mexican ichthyologist Adán E. Gómez González, who tragically passed away in January 2018. P. adani is diagnosed from all congeners by the absence of a humeral spot in individuals larger than 45 mm SL.

Dominguez-Cisneros, Sara E & Ernesto Velázquez-Velázquez, Caleb D. McMahan, Wilfredo A. Matamoros. 2021. "A new species of killifish of the genus Profundulus (Atherinomorpha: Profundulidae) from the upper reaches of the Papaloapan River in the Mexican state of Oaxaca". Ichthyology & Herpetology. 109(4):949–957 - [摘要] · (ffm01006)

创建者 Juan Miguel Artigas Azas (05-2月-2020)

A new species of livebearer fish: Poeciliopsis jackschultzi from the state of Sonora in Mexico has been recently described by Kevin Conway, Mariana Mateos and Robert C. Vrijenhoek in the journal Zookeys. The new species is currently only known from four sites in the Río Concepción, where it is sympatric with P. occidentalis. It is mainly diagnosed by the absence of a black spot at base of the frontal part of the dorsal fin on males, unique in the Leptorhaphis species group of Poeciliosis. The specific name is given to honor Jack Schultz, a pioneer of studies on hybridization and all-female reproduction in Poeciliopsis.

Conway, Kevin W & Mariana Mateos, Robert C. Vrijenhoek. 2019. "A new species of the live-bearing fish genus Poeciliopsis from northern Mexico (Cyprinodontiformes, Poeciliidae)". Zookeys. (883):91-118 - [摘要] · (ffm00905)