File:Guiyu oneiros trunk scales.webp

English: Trunk scales (M2) of Guiyu oneiros. (A,B) Gross anatomy of a trunk scale in crown (A) and basal (B) views. (C,D) Landmarks and length variables of a scale in crown (C) and basal (D) views. (E) Scatter plot of the scales in the CVA space of the first two canonical variate (discriminant) axes. b.m.v, ventral margin of base; c.m.d, dorsal margin of crown; c.m.p, posterior margin of crown; c.m.v, ventral margin of crown; g.a, anterior groove of the base; g.p, posterior groove of the base; h.s, scale height; l.a, anterior ledge; l.p, posterior ledge; p.ad, anterodorsal process; se, serration; L1–L8, first to eighth length variables; 1–11, landmarks 1–11. Landmark 1, tip of the peg; Landmark 2, tip of the anterodorsal process; Landmark 3, midpoint of the dorsal margin of crown; Landmark 4, intersection of the anterior margin of crown and the anterodorsal process; Landmark 5, intersection of the dorsal and posterior margins of crown; Landmark 6, projective point in the anterior margin

of crown (or base) of Landmark 5; Landmark 7, intersection of theposterior and ventral margins of crown; Landmark 8, projective point in the posterior margin of the base of Landmark 5; Landmark 9, intersection of the posterior and dorsal margins of base; Landmark 10, intersection of the posterior and ventral margins of base; Landmark 11, the intersection of the keel and the ventral margin of base (or the rim of the socket). L1, the

length of the peg; L2, the length of the keel; L3, the length of the anterodorsal process; L4, the length of scale in the longitudinal body axis; L5, the length of the scale; L6, the length of the posterior margin of crown (or the height of the scale); L7, the length of the concealed field; and L8, the length of the posterior margin of base. Scale bar = 0.5 mm.