Awesome... Antennae? or Forks?

 Walliserops, a genus consisting of four recognized species, is a really interesting group of trilobites. Known from Devonian rocks of Morocco, there are a number of interesting anatomical features in these trilobites. All species of Walliserops exhibit some asymmetry, that is, the halves of their bodies are not identical on both sides, due to the curvature of the spine on the occipital lobe of the cephalon. Three spines in total originate from the cephalon. The occipital spine in the middle and farthest back (most caudal) and two more lateral spines located near or on the palpebral lobes, caudal to the compound eyes. Many trilobites have some kinds of spines on the cephalon or on the thorax (or both) and these are not what make this genus so interesting. What makes them truly interesting is the trident shaped fork protruding from the forward-most ridge of the cephalon. Each species has a distinctly shaped and different length trident. The exact purpose these tridents is not understood and, at one point, it was thought that they signalled differences between the sexes. This has been considered an interesting hypothesis, but is not considered a fact, as there is not enough evidence to support this claim. A plausible hypothesis states that the tridents were likely similar to the horns of the rhinoceros beetle, which are used for sparing against rivals during mating season and occasionally for digging. Of course, whatever the reason for the trident, it is a very interesting anatomical structure and makes the members of this genus appear very well protected (considering all of their spines as well).

Sources to Consider:

Brett, K. and Chatterton, N. (2001). Parabolops, a new asteropygine trilobite from southern Morocco with an unusual trident-like anterior cephalic frontal process. 3rd International Conference on Trilobites and their Relatives. University of Oxford.

Knell, R. J. and Fortey, R. A. (2005). "Trilobite spines and beetle horns: sexual selection in the Palaeozoic?". Biology Letters. 1: 196–199. doi:10.1098/rsbl.2005.0304. 

Whittington, H. B. (1997). "Mode of Life, Habits and Occurrence". In R. L. Kaesler (ed.). Treatise on Invertebrate Paleontology, Part O, Arthropoda 1, Trilobita, revised. Volume 1: Introduction, Order Agnostida, Order Redlichiida. Boulder, Colorado & Lawrence, Kansas: The Geological Society of America, Inc. & The University of Kansas.