Order: Proetida Salter, 1864
Family: Aulacopleuridae Angelin, 1854
Cyphaspis is a small to medium-sized Devonian trilobite belonging to the Otarioninae. Moroccan species occur from the Pragian to the Givetian and show a remarkable diversity of head shape, eye size, spines, and ornamentation. The genus is especially common in the Anti-Atlas region, including localities such as Foum Zguid, Zguilma, Tadachacht, Khraid, Issoumour, Boudib, Oufatène, Maharch, Mdâour el Kbîr, Talawarite, and Zireg.
Moroccan Devonian species include:
- Cyphaspis agayuara
- Cyphaspis bluhmi
- Cyphaspis cf. ceratophthalmus
- Cyphaspis eberhardiei
- Cyphaspis eximia
- Cyphaspis foumzguidensis
- Cyphaspis hamidi
- Cyphaspis heisingi
- Cyphaspis ihmadii
- Cyphaspis juergenhollandi
- Cyphaspis khraidensis
- Cyphaspis kippingi
- Cyphaspis lerougei
- Cyphaspis maharchensis
- Cyphaspis smeenki
- Cyphaspis tadachachtensis
- Cyphaspis walteri
How to identify Cyphaspis
Most Cyphaspis species can be recognized by:
- A strongly inflated glabella (central lobe of the head).
- Large eyes, often elevated above the cheeks.
- Long genal spines extending from the rear corners of the head.
- A dorsal spine or tubercle on the sixth thoracic segment.
- A relatively small pygidium.
How to separate Cyphaspis from similar genera
Cyphaspis is similar to Chamaeleoaspis and Aulacopleura.
These genera are both small spiny trilobites and can appear similar at first glance.
If your trilobite has a swollen glabella, large eyes and a compact body, it is more likely you have a cyphaspis.
If the head has strong spines, is flatter overall and eyes are less prominent, you likely have a Chamaeleoaspis.
If the body is longer and the cepahlon is relatively simple, you likely have an Aulacopleura.
2. KEY FEATURES OF CYPHASPIS
- Inflated glabella.
- Small to moderately sized pygidium.
- Long genal spines in many species.
- Eyes ranging from small to very large depending on species.
- Usually 11 thoracic segments.
- Sixth thoracic segment commonly bears a spine or tubercle.
- Ornamentation varies from nearly smooth to densely granulated.
3. SPECIES OF CYPHASPIS
Cyphaspis agayuara (Emsian)
- Primitive-looking species.
- Inflated glabella.
- Small eyes with coarse tuberculation around them.
- Long genal spines, reaching approximately the rest of the lenght of the body.
- Long dorsal thoracic spine.
Cyphaspis bluhmi (Eifelian)
- Small species with large eyes
- Weakly inflated glabella.
- Long genal spines reaching near the pygidium.
- Fine ornament over most of the cephalon.
Cyphaspis cf. ceratophthalmus (Eifelian)
- Tall eyes.
- Strongly inflated glabella.
- Long, slender genal spines.
- Similar to the German species ceratophthalmus
Cyphaspis eberhardiei (Emsian)
Similar to C. agayuara but generally has a less spinose occipital node, a more localized patch of coarse tubercles beside the eyes, and fewer coarse tubercles on the thorax.
Cyphaspis eximia (Eifelian)
- Extremely vaulted cephalon.
- Very high glabella.
- 4 distinctive short glabellar tubercles.
- Long dorsal and genal spines.
- One of the easiest Moroccan species to recognize.
Cyphaspis foumzguidensis (Eifelian)
- Weakly inflated and flattened glabella with dense granulation
- Weakly vaulted cephalon.
- Small teardrop-shaped L1 lobes.
Cyphaspis hamidi
Cyphaspis heisingi (Pragian)
- Primitive member of the genus.
- Inflated glabella.
- Small eyes.
- Long thoracic spine.
- Transitional between Silurian and later Devonian species.
Cyphaspis ihmadii (Givetian)
- Late survivor of the primitive agayuara group.
- Retains classic Cyphaspis appearance with inflated glabella and thoracic spine.
Cyphaspis juergenhollandi (Eifelian)
- Teardrop-shaped glabella.
- Long genal spines.
- Fine ornament on borders and cheeks.
- Intermediate in appearance between C. lerougei and C. kippingi.
Cyphaspis khraidensis (Emsian)
- Primitive agayuara-group species.
- Inflated glabella.
- Small eyes.
- Strong dorsal thoracic spine.
Cyphaspis kippingi (Emsian)
- Sword-shaped genal spines.
- Small dorsal spine on sixth thoracic segment.
- Weakly inflated cephalic border.
- Evenly distributed cephalic tubercles.
Cyphaspis lerougei (Emsian)
- Subcircular glabella.
- Very robust genal spines and sparse ornament
- Tiny pygidium with only weakly developed posterior rings.
Cyphaspis maharchensis (Pragian)
- Primitive agayuara-group species.
- Small eyes.
- Inflated glabella.
- Long thoracic spine.
Cyphaspis smeenki (Eifelian)
- Nearly smooth cephalon
- Straight genal spines.
- Trapezoidal cephalic outline.
- Very long thoracic spine.
- Easy to recognize because the head is almost smooth.
Cyphaspis tadachachtensis (Emsian)
- Primitive agayuara-group morphology.
- Inflated glabella.
- Small eyes.
- Well-developed thoracic spine.
Cyphaspis walteri (Eifelian)
- Eifelian species with typical Cyphaspis characters.
- Inflated glabella and genal spines.
- Has two very typical ‘devil’ horns on its glabella