FIGURE 1. Distribution of Mesozoic Czekanowskiales fossils in China (Chinese basemap from the Standard Map Service, plan approval number: GS (2020) 4619).
FIGURE 2. Fossils and schematic diagram of the leaf morphology and epidermal structure of Czekanowskiales. (A) Phoenicopsis angustifolia; (B) Czekanowskia rigida; (C) Phoenicopsis speciosa; (D) schematic diagram of the leaf morphology of Czekanowskiales, dotted line ab indicating the leaf cluster length (or lobe length), dotted line cd indicating the leaf cluster width, line ef indicating the lobe width, and angle cbd indicating the angle between bc and bd (the most lateral lobes); (E) schematic diagram of the epidermal structure of Czekanowskiales. Scale bars (A-C) equal 1 cm.
FIGURE 3. Dendrogram of 35 species of the Czekanowskiales from China.
FIGURE 4. Trait importance scores for genus and species identification and heatmap of correlations between traits. (A) Importance scores for traits identified genus and species, with the solid symbols indicating key traits and the hollow symbols indicating nonkey traits; (B) proportion of importance scores for macro traits and cuticular traits identified at the genus and species; (C) heatmap of correlations between traits; serial numbers correspond to traits in Table 2.
FIGURE 5. Accuracy distributions of five supervised learning algorithms and confusion matrix of the best algorithm. (A) Accuracy distribution of the five algorithms in genus-level identification (using mixed-key traits); (B) CART algorithm confusion matrix (using mixed-key traits); (C) accuracy distribution of five algorithms in genus-level identification (using only macro-key traits); (D) CART algorithm confusion matrix (using only macro-key traits); (E) accuracy distribution of five algorithms for species-level identification (using mixed-key traits); (F) LR algorithm confusion matrix (using mixed-key traits); (G) accuracy distribution of five algorithms for species-level identification (using only macro-key traits); (H) CART algorithm confusion matrix (using only macro-key traits). Genus abbreviations: Cz., Czekanowskia; Ph., Phoenicopsis; Sp., Sphenarion; So., Solenites.
