美國(guó)生物學(xué)家最近在巴西境內(nèi)的亞馬遜雨林發(fā)現(xiàn)了一種新螞蟻，初步認(rèn)定這可能是最古老螞蟻的后代,。由于這種螞蟻有許多前所未見的特征,，生物學(xué)家稱之為“火星來(lái)的螞蟻”,。
來(lái)自得克薩斯大學(xué)的克里斯蒂安·拉伯爾等人在新一期美國(guó)《國(guó)家科學(xué)院院刊》（PNAS）上介紹說(shuō)，這種螞蟻通體呈金黃色,，在土壤中生存,，體長(zhǎng)2到3毫米，沒(méi)有眼睛,，但有很大的大顎,。由于它是肉食性螞蟻，拉伯爾等人猜測(cè)它的大顎是捕食的利器,。
經(jīng)過(guò)形態(tài)學(xué)和基因分析,，拉伯爾等人將這種螞蟻歸入單獨(dú)一個(gè)亞科。這是自1923年以來(lái),，科學(xué)家第一次發(fā)現(xiàn)隸屬于新亞科的活螞蟻,，其他的新亞科螞蟻都是以化石形式被發(fā)現(xiàn)的。目前已知的螞蟻亞科共有21個(gè),。
對(duì)這種螞蟻腿部的DNA（脫氧核糖核酸）分析結(jié)果顯示,，這種螞蟻很可能是最古老螞蟻家族的后裔，處于螞蟻進(jìn)化樹的最初始階段,。
螞蟻和黃蜂有著共同的祖先,，大約在距今1.2億年前，在進(jìn)化道路上“分家”,。螞蟻的種類相當(dāng)豐富,，具有重要的生態(tài)學(xué)研究?jī)r(jià)值。拉伯爾說(shuō),，這一新發(fā)現(xiàn)將有助于生物學(xué)家更好地理解螞蟻的生物多樣性和進(jìn)化歷程,，“這種新螞蟻的發(fā)現(xiàn)說(shuō)明，可能還有很多新的螞蟻種類,，甚至是巨大的進(jìn)化線索埋藏在熱帶雨林的土壤中”,。（生物谷Bioon.com）
生物谷推薦原始出處：
PNAS，doi: 10.1073/pnas.0806187105,，Christian Rabeling,，Manfred Verhaagh
Newly discovered sister lineage sheds light on early ant evolution
Christian Rabeling, Jeremy M. Brown, and Manfred Verhaagh
Ants are the world's most conspicuous and important eusocial insects and their diversity, abundance, and extreme behavioral specializations make them a model system for several disciplines within the biological sciences. Here, we report the discovery of a new ant that appears to represent the sister lineage to all extant ants (Hymenoptera: Formicidae). The phylogenetic position of this cryptic predator from the soils of the Amazon rainforest was inferred from several nuclear genes, sequenced from a single leg. Martialis heureka (gen. et sp. nov.) also constitutes the sole representative of a new, morphologically distinct subfamily of ants, the Martialinae (subfam. nov.). Our analyses have reduced the likelihood of long-branch attraction artifacts that have troubled previous phylogenetic studies of early-diverging ants and therefore solidify the emerging view that the most basal extant ant lineages are cryptic, hypogaeic foragers. On the basis of morphological and phylogenetic evidence we suggest that these specialized subterranean predators are the sole surviving representatives of a highly divergent lineage that arose near the dawn of ant diversification and have persisted in ecologically stable environments like tropical soils over great spans of time.
