|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Trilobita - Redlichiida - Holmiidae
It was assigned to Holmiidae by Whittington et al. (1997); to Olenellida by Sepkoski (2002); and to Holmiinae by Palmer and Repina (1993), Lieberman (1999) and Ebbestad et al. (2003).
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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.
|A. R. Palmer and L. N. Repina 1993||Holmiinae with outline of cephalon subpentagonal; genal spine prominent, originating oppo- site or anterior to S3; short intergenal spine or node lo- cated at or on axial side of intergenal angle. Glabella expanded anteriorly. Posterior tips of ocular lobes opposite or posterior to Li. Pygidium large, wider than long, of at least 3 segments; anterior two segments extended into short border spines.|
|B. S. Lieberman 1999||Anterior cephalic border developed as flattened plane, prominently separated from extraocular area by furrow; frontal lobe contacts anterior border furrow, lateral mar- gins distal to lateral margins of L0, expands prominently dorsally; anterolateral margins of glabella prominently separated from extraocular area by furrow; length (sag.) of frontal lobe 1 to 1.1 times length (sag.) of L0 and L1; dorsal notch-like truncation in ocular lobes where they contact frontal lobe of the glabella; anterodistal margins of L3 formed by axial furrows; distal margins of L3 straight; S3 evenly convex, medial and distal tips as far for- ward; lateral margins of glabella opposite L2 subparallel; S1, S2 and S3 not conjoined me- dially; medial and distal tips of S2 as far forward; line from posterior edge of ocular lobe to junction of lobe with glabella forms roughly 10 to 15 degree angle with sagittal line; poste- rior margin of ocular lobe opposite distal tip of S0; lateral lobes present on L0; node or spine on L0 posterior of midline; intergenal angle with small spine directly behind distal tip of ocular lobe; intergenal angle forms 80 to 90 degree angle with transverse line; extraocu- lar region prominently vaulted, very narrow, width (tr.) at L1 10% to 15% width of glabella at L1; genal spine angle opposite distal tip of L3 or L4; lateral margin of genal spine near spine angle forms roughly 60 to 70 degree angle relative to sagittal line; pygidium twice as wide (tr.) as long (sag.), posterior margin notched.|