Mesonacis wileyi Gapp & Lieberman, 2014, sp. nov.

• Main Authors: Gapp, I. Wesley, Lieberman, Bruce S.
• Format: Other/Unknown Material
• Language: unknown
• Published: 2014
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Trilobita; Redlichiida; Olenellidae; Mesonacis; Mesonacis wileyi; Northwest Territories; Canada; Mackenzie mountains
• Online Access: https://zenodo.org/record/6136072; https://doi.org/10.5281/zenodo.6136072

Mesonacis wileyi sp. nov. Fig. 4 Type material. Holotype KUMIP 355550. Paratypes KUMIP 355551 and PWNHC-2013.23.4- 5. Olenellus zone or Waucoban Series, Dyeran stage, sensu Webster (2011 a, b) and Webster et al. (2011), early Cambrian, Sekwi Formation, Mackenzie Mountains, Northwest Territories, Canada, Section 4, 430 – 435m above the base of section; Section 3, 700 – 800m above the base of the section. Etymology. In honour of Edward O. Wiley, University of Kansas, for his fundamental contributions to the field of phylogenetics. Diagnosis. LA does not contact anterior cephalic border furrow; width of extraocular area approximately equal to width (tr.) of glabella at L 1; posterior border between LO and intergenal angle parallel to a transverse line; intergenal angle 45 to 50 degrees relative to a transverse line; genal spines terminate posteriorly opposite T 5 or T 6. Description. Anterior cephalic border developed as a raised ridge, length (sag.) directly anterior of LA is approximately 0.5 times length (sag.) LO; small preglabellar field; anterolateral margin of LA directed posteriorly at approximately 45 degrees; LA length (sag.) equal to the combined length (sag.) of LO and L 1; ocular furrow present; ocular lobes extend back to SO; S 3 convex anteriorly, conjoined adaxially; abaxial margins of L 2 adaxial of abaxial margins of L 3; S 1 and SO both conjoined adaxially; L 1 length (sag.) approximately length (sag.) of LO; abaxial margins of L 1 adaxial to abaxial margins of LO; posterior margin of LO convex posteriorly; extraocular area relatively wide, with prominent anastomosing ridges; posterior border between intergenal angle and LO is parallel to a transverse line; intergenal angle deflected anteriorly at 45 to 50 degrees; genal spine narrow, developed opposite L 1 or S 1, extends back to T 5 or T 6; prothorax consists of 13 (?) segments and opisthothorax about 5 or 6; pleural spines long and directed posteriorly; T 3 is macropleural with spines extending posterior of pygidium; axial spine is present, ...