The families of flowering plants

L. Watson and M.J. Dallwitz

Petermanniaceae Hutch.

~ Philesiaceae p.p.

Habit and leaf form. Lianas (with prickly stems). Rhizomatous. Climbing; tendril climbers (the tendrils derived from inflorescences, the stems also twining). Mesophytic. Leaves alternate; spiral; petiolate to subsessile; non-sheathing; simple. Lamina entire; oblong; pinnately veined (pinnate-parallel); cross-venulate. Leaves exstipulate. Lamina margins entire.

Leaf anatomy. Stomata present; anomocytic. The mesophyll containing crystals. The crystals raphides. Foliar vessels absent.

Axial (stem, wood) anatomy. Secondary thickening absent. The axial xylem with vessels, or without vessels.

The vessel end-walls scalariform.

Root anatomy. Root xylem with vessels; vessel end-walls scalariform.

Reproductive type, pollination. Plants hermaphrodite. Floral nectaries present, or absent (? — no septal nectaries).

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in panicles. The ultimate inflorescence units cymose. Inflorescences leaf-opposed; raceme-like, paniculate. Flowers regular; 2 merous; cyclic; pentacyclic. Perigone tube absent.

Perianth of ‘tepals’; 6; free; 2 whorled; isomerous; sepaloid, or petaloid (?); similar in the two whorls.

Androecium 6. Androecial members free of the perianth; free of one another; 2 whorled. Androecium exclusively of fertile stamens. Stamens 6; diplostemonous. Anthers dehiscing via longitudinal slits; extrorse; tetrasporangiate. Pollen shed as single grains. Pollen grains aperturate; 1 aperturate; sulcate.

Gynoecium 3 carpelled. Carpels isomerous with the perianth. The pistil 1 celled. Gynoecium syncarpous; eu-syncarpous; inferior. Ovary 1 locular. Gynoecium stylate. Styles 1. Stigmas 1; capitate. Placentation parietal. Ovules in the single cavity 15–50 (‘fairly numerous’).

Fruit fleshy; indehiscent; a berry; 15–100 seeded (‘many’ seeded). Seeds endospermic. Testa without phytomelan (?).

Geography, cytology. Australian. Sub-tropical to tropical. Eastern Australia.

Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Liliiflorae; Dioscoreales. APG 3 core angiosperms; Superorder Lilianae; non-commelinid Monocot; Order Liliales.

Species 1. Genera 1; only genus, Petermannia.

Illustrations. • Petermannia cirrosa: Hook. Ic. Pl. 14 (1881).

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG). See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 13th March 2017.’.