阿加斯菊石（学名：Agathiceras sp.），是古生代末期及中生代早期繁盛的菊石类，现已灭绝。牠主要产于印尼、东帝汶及哈萨克斯坦等地区，其中以前两者为最多。

由于是用人名当做学名，所以是直接音译的。阿加斯菊石在大陆也翻译为团线菊石。

阿加斯菊石属于阿加斯菊石属（学名：Agathiceras），属于独自的阿加斯菊石科（学名：Agathiceratidae），是一种广泛存在（例如：在乌拉尔，西西里岛和得克萨斯州。）而存量丰富的近球状的棱菊石目物种，从下宾夕法尼亚到中二叠世的沉积物广泛出现。

阿加斯菊石属由Gemmellaro在1887年的中二叠世的西西里岛物种A. suessi命名。

Agathiceras is a subglobose goniatitid from the family Agathiceratidae, widespread and locally abundant in Lower Pennsylvanian to Middle Permian sediments, e.g. the Urals, Sicily, and Texas.

Agathiceras, named by Gemmellaro in 1887 from the Middle Permian Sicilian species, A. suessi, has a broadly rounded outer edge, known as the venter, being at the lower side of the animal during life, and a deeply impressed innerside, the dorsum which corresponds with the back or dorsal side of the animal. The sutures are goniatitic with three lateral and one dosolateral lobes on either side. Those that are external are spatulate, those hidden are V-shaped. The siphuncle is primitive with the septal necks pointing to the rear, a condition known as retrosiphonate.