Micromalthidae is a small relictual family of archostematan beetles that is well known for its unusual asexual reproductive system characterised by parthenogenetic, viviparous, larviform females and sterile adults. Here we describe the first micromalthid beetle from mid-Cretaceous Burmese amber (ca.100Ma). Protomalthus burmaticus gen. et sp. nov. differs from all presently known micromalthid beetles by the presence of distinct frontoclypeal, labroclypeal, and medicranial sutures. The finding represents the first Mesozoic record of an adult micromalthid beetle and confirms a Gondwanan distribution of the family during the Cretaceous. A list of micromalthid beetles is provided, together with a key to extant and fossil species.

中文翻译：

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缅甸琥珀中一新属新种Micromalthidae（鞘翅目：Archostemata）

Micromalthidae 是一种小型孑遗甲虫科，以其不寻常的无性生殖系统而闻名，其特征是孤雌生殖、胎生、幼虫状雌性和不育成虫。在这里，我们描述了来自白垩纪中期缅甸琥珀的第一只微型甲虫（约100 毫安）。缅甸原虫将军 等人。十一月 与所有目前已知的微型甲虫的不同之处在于存在明显的前唇、唇裂和颅内缝合线。这一发现代表了成年微型甲虫的第一个中生代记录，并证实了该科在白垩纪期间的冈瓦南分布。提供了一份微型甲虫清单，以及现存和化石物种的钥匙。