Wingia cf. expansolobum (Upchurch and Dilcher) Wang & Dilcher, 2018

Wang, Hongshan & Dilcher, David L., 2018, Early Cretaceous angiosperm leaves from the Dakota Formation, Hoisington III locality, Kansas, USA, Palaeontologia Electronica (34 A) 21 (3), pp. 1-49 : 38

Wingia cf. expansolobum (Upchurch and Dilcher) comb. nov.

Figure 24

Description. Leaf simple, five-lobed, leaf 4 cm long and 8 cm wide (estimated maximum width); sinus deep, extending 75% to 80% of distance from apex to lamina base; medial lobe narrow ovate, symmetrical; lateral lobes asymmetrical, curved apically; apex of lobes obtuse or slightly acute; base of lamina obtusely cuneate or truncate; margin toothed; sinus rounded; serrations minute, simple; serration type ranging from concave to straight on apical side and straight to convex on basal side, spacing irregular; typically three veins entering a tooth, medial vein originating from exmedial side of secondary vein, basal vein tertiary in order and running very close to the margin before entering the tooth, vein of apical side not well developed. Petiole not observed. Primary venation basal actinodromous; primary veins thin, multi-stranded; medial primary vein straight in course; inner lateral primary veins apically curved; outer primary veins apically curved. Secondary venation semicraspedodromous; secondary veins thick relative to primary veins; originating from primary veins at moderate acute angle, slightly curved. One pair of secondary veins in each lobe originating from the extreme base of the leaf lamina and running almost parallel to the primary veins for almost half of the lobe length before joining the secondary veins originated from the primary veins within the lobes. Tertiary veins orthogonal reticulate. Veins of higher order not observed.

Number of species examined. 2.

Specimens illustrated. UF 15705-14824 ( Figure 24.1, 24.3 ); 24460 ( Figure 24.2 ).

Remarks. These two specimens are placed in Wingia cf. expansolobum . They differ from Wingia expansolobum in having smaller leaves, relatively thin secondary veins, a pair of distinctive secondary veins originating from the extreme base of the leaf lamina and running parallel to the primary veins for almost half of the lobe length, semicraspedodromous secondary venation, and a predominately toothed margin. Even leaves of the same size ( Figure 21.4 ) of Wingia expansolobum have different venation patterns. We currently separate these two specimens from Wingia expansolobum because of these differences.

Figures

FIGURE 21. Wingia expansolobum (Upchurch and Dilcher) comb. nov. 1, UF15706-30158a, specimen showing a complete leaf. Note the long petiole with a swollen base and the extension of lamina tissue on the petiole. Scale bar equals 1 cm. 2, Enlargement of the petiole in Figure 21.1 to show the swollen base. Scale bar equals 2 mm. 3, UF15706-30158b, enlargement of a leaf on the back of the same specimen to show high order venation and glandular teeth. Scale bar equals 3 mm. 4, UF15706-24788, specimen showing a deeply lobed leaf. Note apically curved outer lateral lobes. Scale bar equals 1 cm.

FIGURE 24. Wingia cf. expansolobum (Upchurch and Dilcher) comb. nov. 1, UF15706-14824, specimen showing two complete and two broken lobes. Note thin venation and glandular teeth. Scale bar equals 3 mm. 2, UF15706-24460, specimen showing five lobes. Note that two lobes (indicated by arrows) are broken. Scale bar equals 1 cm. 3, Enlargement of Figure 24.1 (area indicated by arrow) to show glandular teeth. Scale bar equals 1 mm.