|Basic info||Taxonomic history||Classification||Relationships|
|Morphology||Ecology and taphonomy||External Literature Search||Age range and collections|
Trilobita - Redlichiida - Holmiidae
It was assigned to Callaviinae by Palmer and Repina (1993); to Holmiidae by Whittington et al. (1997); to Olenellida by Sepkoski (2002); and to Holmiinae by Nikolaisen (1986), 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||Callaviinae with posterior margin of cephalon nearly straight or deflected slightly forward distal to intergenal swellings, which are located closer to genal angle than to axial furrows|
|B. S. Lieberman 1999||Anterior cephalic border not prominently separated from extraocular area by deep furrow, developed as flattened, angled plane; frontal lobe contacts anterior border fur- row, does not expand prominently dorsally; lateral margins of L4 directly anterior to lateral margins of L0; anterolateral margins of glabella not prominently separated from extraocu- lar area by furrow; length (sag.) of frontal lobe equal to 1.5 times length (sag.) of L0 and L1; pre-ocular furrow on frontal lobe directed inward and forward from glabellar margin; an- terodistal margins of L3 formed by ocular lobes; postero- and anterodistal margins of L3 with same orientation; lateral margins of glabella opposite L2 diverging when proceeding anteriorly; posterior margins of ocular lobes opposite distal tip of S0; line from posterior margin of ocular lobe to junction of posterior margin of lobe with glabella forms 20 to 25 degree angle relative to sagittal line; S3 evenly convex, distal tip further forward than medial tip; distal tip of S2 further forward than medial tip; S0, S1, S2 and S3 conjoined medially; S0 sinuous; L0 with spine posterior of midline of L0; lateral lobes on L0 present; intergenal angle developed midway between ocular lobe and genal spine, with small spine; intergenal angle forms 10 to 15 degree angle with transverse line; extraocular area gently sloping from eye to lateral border furrow, width (tr.) opposite L1 equal to 45% to 55% width of glabella at L1; genal spine angle opposite medial part of distal margin of L0; genal spine close to genal spine angle forms roughly 10 to 15 degree angle relative to sagittal line; genal spine extends back roughly 4 to 5 thoracic segments.|