Here are some representative Asaphoidea:
| ORDER ASAPHIDA Superfamily Anomocaroidea Superfamily Asaphoidea Superfamily Cyclopygoidea Superfamily Trinucleioidea Superfamily Dikelokephaloidea Superfamily Remopleuridoidea |
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Superfamily
Asaphoidea |
Ogygiocaris |
Asaphus |
Isotelus |
Neoasaphus |
Compare the pictorial approach to the narrative equivalent below (salient features in color):
| ORDER ASAPHIDA
Introduction: A large (comprising perhaps 20% of trilobite species) and morphologically diverse order of trilobites, most advanced families united by similar ontogeny (the ovoid, effaced "asaphoid" protaspid form with enrolled doublure); most members also have a median ventral suture (only secondarily lost via fusion in two advanced families). Cephalon: often equal/subequal to pygidium (e.g., Asaphoidea), but some not so (e.g., Trinucleioidea); usually with a high degree of cephalic effacement so glabellar furrows are faint or not visible; eyes usually large (some forms secondarily blind); preoccipital glabellar tubercle in advanced forms; cephalic doublure often wide, with terrace ridges; librigena are typically separated by a ventral median suture; dorsal anterior facial sutures often curve adaxially to meet in front of the glabella; sutures opisthoparian; hypostome conterminent or impendent, with only primitive forms (e.g., the Anomocaroidea) natant. Thorax: typically 5 – 12 segments, but 2 - 3 in a few Trinucleioidea, 13+ in some Anomocaroidea, up to 30 in an Alsataspidid (Trinucleioidea). Pygidium: typically large (subisopygous to macropygous), with a wide doublure. Occurrence: Middle-Upper Cambrian boundary to upper Ordovician-lower Silurian. Suborders: None (or nominate Asaphina). Superfamilies: Anomocaroidea, Asaphoidea, Dikelokephaloidea, Remopleuridoidea, Cyclopygoidea, Trinucleioidea. Superfamily Asaphoidea
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| Anomocaroidea | Asaphoidea | Cyclopygoidea | Trinucleioidea | Dikelokephaloidea | Remopleuridoidea |
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