摘要：The researchers said the 16-centimeter-long tadpole died during the larval period, or stage, of frog development.

Scientists in Argentina have discovered the oldest-known remains of the tadpole.

阿根廷科学家发现了已知最古老的蝌蚪化石。

The animal belonged to a large frog species that lived alongside dinosaurs about 161 million years ago.

这种动物属于大约1.61亿年前与恐龙生活在一起的一种大型青蛙。

The researchers said the 16-centimeter-long tadpole died during the larval period, or stage, of frog development.

研究人员说，这只16厘米长的蝌蚪在青蛙发育的幼虫期或阶段死亡。

The discovery is providing new information about the development of frogs and toads.

这一发现为青蛙和蟾蜍的发育提供了新的信息。

The remains suggest tadpoles today are largely unchanged from their ancestors in the ancient time called the Jurassic period.

这些化石表明，今天的蝌蚪与它们在侏罗纪时期的祖先在很大程度上没有变化。

The oldest-known frog remains date back even further, though no older tadpole fossils have been found.

虽然没有发现更古老的蝌蚪化石，但已知最古老的青蛙化石可以追溯到更久远的年代。

The remains are in good condition.

遗骸保存完好。

In fact, researchers say, the ancient tadpole has some soft tissues rarely seen in fossils.

事实上，研究人员说，这只古老的蝌蚪有一些在化石中很少见到的软组织。

The tadpole's eyes and nerves, for example, appear as dark markings in the fossil.

例如，蝌蚪的眼睛和神经在化石中呈现为黑色标记。

Fossil hunters found the tadpole in 2020, during a dig for dinosaur remains on a ranch in the southern province of Santa Cruz.

化石猎人于2020年在南部圣克鲁斯省的一个牧场挖掘恐龙遗骸时发现了这只蝌蚪。

The fossil includes the tadpole's head and most of its body.

化石包括蝌蚪的头部和大部分身体。

Frogs have a two-stage life cycle, with the tadpole larva developing into the adult form.

青蛙的生命周期分为两个阶段，由蝌蚪幼虫发育为成虫。

This tadpole was in the late stages of development.

这只蝌蚪处于发育的后期。

Adults of this species are a similar length as the tadpole, the researchers said.

研究人员说，这个物种的成虫和蝌蚪一样长。

"It's not only the oldest tadpole in the world and amazingly preserved, but it also tells us about the size of one of the few frog species known from that time," said biologist Mariana Chuliver of Fundación Azara-Universidad Maimónides.

Fundación Azara-Universidad Maimónides的生物学家Mariana Chuliver说：“它不仅是世界上最古老的蝌蚪，保存得非常完好，而且它还告诉我们当时已知的一种青蛙的大小。”

Chuliver was the lead writer of the study that appeared recently in the scientific publication Nature.

Chuliver是最近发表在科学杂志《自然》上的这项研究的主要作者。

Chuliver said the soft tissue remains are important because they permit researchers to "know the diet and lifestyle of these organisms." The remains, Chuliver added, show that the form and structure of tadpoles have "remained almost unchanged over the last 160 million years." I'm John Russell.

Chuliver说，软组织遗骸很重要，因为它们能让研究人员“了解这些生物的饮食和生活方式”。Chuliver补充说，这些遗骸表明，蝌蚪的形态和结构“在过去的1.6亿年里几乎没有改变”。我是约翰·罗素。

来源：英语东