Сообщество, посвящённое ра - Post a comment
( Read Comments )
TimeText
12:53 pm

[info]industrialterro

[Link]

Corynexochida

 Corynexochida is an order of trilobite that lived from the Lower Cambrian to the Middle Devonian. Like many of the other trilobite orders, Corynexochida contains many species with widespread characteristics.

 The middle region of the cephalon (the glabella) is typically elongate, with the sides often spreading forward (pestle-shaped). Some species have glabellae that are effaced, meaning they are smooth and show little detail. The glabellar furrows (when not effaced) typically have a splayed arrangement. In most species, the hind pair on either side of the cephalon become spines that point sharply backwards, and the spinose tips of the anterior pairs of thoracic segments tend to become more and more forward directed toward the pygidium. The eyes are typically large. Pygidia are typically large, competing in size with the cephalon in some species.

 The tips of the thoracic segments of many Corynexochida species are spine-like (though in some species they are flush with the sides and smooth). The thorax can have 2-12 segments (rarely more), but they more typically have 7-8.

 

 Репродукция:

 

   

      Oryctocephalus

 

 Временные рамки:

 

  

 

 Ископаемые останки:

 

 

 

 

Reply:
 
From:
Identity URL: 
имя пользователя:    
Вы должны предварительно войти в LiveJournal.com
 
E-mail для ответов: 
Вы сможете оставлять комментарии, даже если не введете e-mail.
Но вы не сможете получать уведомления об ответах на ваши комментарии!
Внимание: на указанный адрес будет выслано подтверждение.
Username:
Password:
Subject:
No HTML allowed in subject
Message:


Powered by LJ.Rossia.org