-
agnostid trilobite. It has a
headshield (or cephalon)
wider than the
tailshield (pygidium), and in
between them
three thoracic body
segments (somites)...
- (or pleurae) are furrowed, and the
articulating facets distinct. The
tailshield (or pygidium) is
always smaller than the
headshield (or cephalon), a situation...
- a small,
rather flat
trilobite with an oval outline, a
headshield and
tailshield of
approximately the same size, 7
articulating segments in the middle...
-
anterior segment to
slightly pointing inwards for the
posterior segment. The
tailshield (or pygidium) is large, subtriangular, and
about two-thirds to three-fourths...
-
genal spines, 5
thorax segments also
ending in
stubby genal spines, and a
tailshield (pygidium) with a pair of m****ive tusk-like spines, and two
smaller spines...
- (or
palpebral area) is flat. The
headshield has a
finer sculpture. The
tailshield (or pygidium) is
weakly furrowed.
These characters distinguish it from...
- (Newfoundland). It can be
recognized by its
strongly effaced headshield and
tailshield, with
narrow but
distinct furrows and
borders along its margins, and three...
- may have an exta
large and wide rib (a
state called macropleural). The
tailshield (or pygidium) is
small but
appears to be
composed of more than one segment...
- sickle-shaped
spines that to the back
curve increasingly further backwards. The
tailshield (or pygidium) is small. HAWLE, J. & CORDA, A. J. C. 1847.
Prodrom einer...
- oval or semi-circular
headshield (cephalon), and a
circular to long oval
tailshield (pygidium)
equal to or
longer than the cephalon,
without any body segments...