重新描述了湖南中泥盆世的锥石Changshaconus carinata Zhu ,1985。通过比较 ,笔者认为Chang- shaconus与产自南非泥盆系和南、北美洲下泥盆统中的Reticulaconularia Babcock et Feldmann ,1986非常相似。Changshaconus和Reticulaconularia两属由于锥管表面横肋间具有纵向脊状构造 ,与横肋构造一起构成了网状的表面装饰 ,从而区别于其它所有锥石类化石。两属的其它特征还包括 :(1)在角沟处 ,横肋成交错状排列 ;(2 )横肋在角沟的肩部向口端明显弯曲 ;(3)面中线呈明显的脊状隆起。以上 3个特征在Climacoconus Sinclair,195 2属中存在 ,因此Changshaconus、Reticulaconularia和Climacoconus构成了一个单系类群 ,而不同于其它锥石类。这 3属又与Notoconularia Thomas,1969和Paraconularia Sinclair,1952两属相似 ,横肋都在角沟处呈交错状排列。

Changshaconus carinata Zhu 1985 a Middle Devonian conulariid from Hunan Province southeastern China is redescribed and refigured．Changshaconus probably was most closely related to Reticulaconularia Babcock et Feldmann 1986 which occurs in the Devonian of South Africa and the Lower Devonian of Bolivia New Jersey and Quebec．Changshaconus and Reticulaconulariadiffer from all other conulariids in having transverse ribs and interspace ridges that are arranged in such a way as to form a reticulate facialornament．Additional characteristics of Changshaconus and Reticulaconularia include （1） interruption plus alternate arrangement and interlocking of the transverse ribs in the corner sulcus；（2） sharp bending of the transverse ribs toward the aperture on the shoulders （edges）of the corner sulcus；（3） midline of the four faces marked by an external ridge．Together these three additional similarities are uniquelyshared with Climacoconus Sinclair 1952 and can be interpreted as evidence that Changshaconus Reticulaconularia and Climacoconuswere members of a single monophyletic taxon that excluded all other conulariids．This group in turn may have been most closely relatedto Notoconularia Thomas 1969and Paraconularia Sinclair 1952 both of which exhibit interruption plus alternation and interlocking ofthe transverse ribs in the corner sulcus．

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