Walliserops
sp
Often called
the short fork Trident Comura
Trilobites
Order Phacopida, Suborder Phacopina, Superfamily Acastoidea, Family Acastidae
Geological
Time: Middle Devonian
Size: Walliserops
trilobite is 65 mm long
Fossil Site:
Foum Ziguid, Zagora , Morocco
Description:
This trilobite is a member of the Order Phacopida, Family Acastidae
from the Devonian deposits of Ziguilma, Morocco known commercially
as the Short Fork Trident Comura. The Chatterton and Brett had
erected the genus Parabolops, with the long-forked trident being
Parabolops neptunis and the short-forked Parabolops hammi (see
my other examples for a fine long-forked example), but the genus
remains Waliiserops at present. Some think the differences may
be the result of sexual dimorphism. Radical differences between
the sexes are common in Arthropods (see some of the scarab beetles,
for example). However, there are some half dozen known variants,
so unless trilobites had a panoply of sexes the theory does not
hold up to scrutiny. Whatever you call it, this is a spectacular
example. It has similarities to Walliserops
hammi in the fact
that it possess a flattened , laterally-projecting occipital
spine,
but also shows features of Walliserops
lindoei in the shape of
the broadened “tines” on the fork, but lacks the
tubular occipital spine of that species. There are several trident
trilobites
yet to be described and this one falls into
that category. For now, I choose to simply refer to it as “Short
Fork Trident”.
Reference: Palaeontograhica Canadiana, No 25, 2006, pp 33-36. |
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