|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Trilobita - Redlichiida - Holmiidae
If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
|B. S. Lieberman 1999||Anterior cephalic border prominently separated from extraocular area by fur- row, border developed as rounded ridge; frontal lobe does not contact anterior cephalic border furrow (variably developed in “P.” cometes); frontal lobe expands prominently dor- sally; anterolateral margins of glabella prominently separated from anterior extraocular area; length (sag.) of frontal lobe equal to 1 to 1.1 times length (sag.) of L0 and L1; S3 evenly convex; notch in ocular lobes where they contact frontal lobe (not in “P.” cometes); S1, S2 and S3 conjoined medially; posterior margin of ocular lobe opposite distal tip of S0 or me- dial part of distal margin of L0; line from posterior margin of ocular lobe to junction of posterior margin of lobe with glabella forms roughly 0 to 15 degree angle with sagittal line; L0 with spine, posterior of midline; intergenal angle with small spine directly behind distal tip of ocular lobe; extraocular region prominently vaulted, width (tr.) at L1 45% to 55% width of glabella at L1; genal spine extends back roughly eight thoracic segments; thoracic pleural spines very short (exsag.), extend back only one segment, lateral margins inclined at 10 to 20 degree angle relative to sagittal line (see Fritz 1995 for additional characters).|