Suborder Eodiscina
: H$ r( _& W& k# {& n1 Z 简介:有争议的Eodiscina放置在Agnostida。在场的眼睛,缝合,典型胸结构表明Eodiscina显然是三叶虫(或者类似于Ptychopariida),整体相似,在Agnostida Agnostina(1997年)中普遍存在的系统处理当前的论述。. L. [8 a j# L* c( T* L9 ~5 V
proparian缝合-:当;有些保留的眼睛;glabella通常简单,可以缩小和塔楼。
) ]8 A( N, h i" A' x. ~2 P* |0 d 胸部:2 / 3的正常胸段表达形式half-rings牙
5 K4 o t4 v# q$ e3 h7 B+ [ Pygidium:轴可狭长,靠近边缘,一般截然分为超过3 ringlike区段;在某些物种的胸腔区域划分,有时pygidial分割抹你浇透地的犁沟,边境经常很深,有时spin-bearing轴。1 m" R" C9 ~$ k
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英文 Suborder Eodiscina
5 ?# g3 \' N' zIntroduction: There is some controversy over the placement of Eodiscina in the Agnostida. Presence of eyes, sutures, and typical thoracic structure suggest that Eodiscina are clearly trilobites (perhaps akin to Ptychopariida), and the overall similarity to Agnostina (and placement in Agnostida) prevails in the 1997 systematic treatment of the current Treatise. 6 D4 x7 m* f" A
Cephalon: with proparian sutures, when present; some retain eyes; glabella usually simple, may be narrow and tapering. / D4 u T# V `4 \; |& k. O
Thorax: 2 or 3 thoracic segments of normal trilobite form, with articulating half-rings ! I) P4 w9 }! e. i! c% O
Pygidium: axis can be long and narrow, extending close to margin, generally distinctly divided into more than 3 ringlike segments; pleural region segmented in some species, sometimes pygidial segmentation effaced; border furrows often very deep; axis sometimes spin-bearing. |