Kipling and Warren, electronic supplement

Appendix S2: Definitions and sources for floral shape categories

Shape Category Description from sources Sources and notesa

Disk Petals are spread out in a (+/-) flat circle. Pollen and A (and B as dish/bowl nectar easily accessible. type)

Brush External surface exclusively or partly formed by A, B sexual organs, perianth split into filiform segments between. Sometimes brush can be dominated by perianth segments or bracts

Club-like Flowers in club-like inflorescence A (not described in detail in source)

Umbel Umbels of many tiny disk-shaped flowers Divided from singly presented disk flowers to take into account visual difference

Basket Assemblage of many flowers with florets or bracts at A, B the edge specifically for display. Individual flowers often long, thin tubes

Funnel Tubular flower with a straight or concave contour, A, B nectar at base of tube

Stalk-plate A disk-shaped, flattened part at the top of a tube or A with spur; when the corolla tube is narrow only insects with a long proboscis can access basal nectar

Butterfly With upright standard and wings covering the keel. A (and B as flag type) Access through weight/forcing of larger insects

Lip Dorsiventral structure with upper and lower lip. A (and B as variant of Narrow corolla tube broadens to lower lip which gullet type) provides a landing platform for insects

Bell Similar to funnel flowers but with the opening A, B pointing down; contour convex a Sources are: A = Barth (1985) and B = Faegri and van der Pijl (1979). Full references can be found in the main paper