The families of flowering plants

L. Watson and M.J. Dallwitz

Phormiaceae J.G. Agardh

~ Variously Agavaceae, Hemerocallidaceae, or Asphodelaceae-Hemerocallidoideae

Including Dianellaceae Salisb.

Habit and leaf form. Sub shrubs, or herbs (medium to tall). Perennial; with a basal aggregation of leaves, or without conspicuous aggregations of leaves; rhizomatous, or tuberous. Helophytic to xerophytic. Leaves medium-sized to very large; alternate; distichous; flat, or folded; commonly leathery (or rigid); ambiguously petiolate to subsessile (by the edgewise compression at the blade/sheath junction), or sessile; sheathing. Leaf sheaths with free margins. Leaves borne edgewise to the stem to ‘normally orientated’ (often semi-equitant, being very strongly compressed proximally but flattened in the normal plane above); simple. Lamina neither inverted nor twisted through 90 degrees; entire; linear; parallel-veined; without cross-venules. Lamina margins often rough or serrulate with antrorse teeth.

Leaf anatomy. The leaf lamina dorsiventral. Stomata present; anomocytic. The mesophyll containing crystals. The crystals raphides (often), or solitary-prismatic (‘pseudoraphides’). Foliar vessels absent.

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

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

Reproductive type, pollination. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in panicles. The ultimate inflorescence units cymose. Inflorescences scapiflorous (often more or less), or not scapiflorous; terminal; sparingly to densely branched, few- to many-flowered panicles. Flowers small to medium-sized; regular to somewhat irregular; when irregular, somewhat zygomorphic. The floral irregularity involving the perianth, or involving the perianth and involving the androecium. Flowers 3 merous; cyclic; pentacyclic. Perigone tube present (short), or absent.

Perianth of ‘tepals’, or with distinct calyx and corolla (dubiously); 6; free, or joined; 2 whorled; isomerous; petaloid (including the outer series); similar in the two whorls, or different in the two whorls (the outer often smaller, sometimes of different texture). Tepal apex trichomes (TAT) present (Agrostocrinum, Corynotheca, Dianella, Excremis, Phormium, Stypandra, Thelionema). Calyx (if the outer whorl so designated) 3; 1 whorled; polysepalous, or gamosepalous; regular, or unequal but not bilabiate. Corolla (if the inner whorl so designated) 3; 1 whorled; polypetalous, or gamopetalous; unequal but not bilabiate, or regular; green, or white, or yellow, or orange, or blue (or violet).

Androecium 6. Androecial members free of the perianth; all equal, or markedly unequal; free of one another (usually), or coherent (rarely); when joined 1 adelphous; 2 whorled (3+3). Androecium exclusively of fertile stamens. Stamens 6; diplostemonous; alterniperianthial. Anthers dorsifixed, or basifixed; dehiscing via pores, or dehiscing via longitudinal slits; introrse; tetrasporangiate. The endothecial thickenings spiral. Microsporogenesis simultaneous. Anther wall of the ‘monocot’ type. Tapetum glandular. Pollen shed as single grains. Pollen grains aperturate; 1 aperturate, or 3 aperturate; predominantly trichotomo- sulcate.

Gynoecium 3 carpelled. Carpels isomerous with the perianth. The pistil 3 celled. Gynoecium syncarpous; eu-syncarpous; superior, or partly inferior (slightly embedded, in Phormium). Ovary 3 locular. Gynoecium stylate. Styles 1; attenuate from the ovary; apical. Stigmas 1; dry type. Placentation axile. Ovules 4–30 per locule (to ‘rather numerous’); arillate, or non-arillate; anatropous; bitegmic; weakly crassinucellate, or tenuinucellate (Dianella). Embryo-sac development Polygonum-type. Antipodal cells formed; 3; not proliferating. Synergids pear-shaped (with filiform apparatus). Endosperm formation helobial.

Fruit fleshy, or non-fleshy; dehiscent, or indehiscent; a berry (sometimes blue), or a capsule. Capsules loculicidal, or septicidal. Seeds endospermic. Endosperm oily. Seeds winged (Phormium), or wingless. Cotyledons 1. Embryo achlorophyllous (2/2). Testa usually encrusted with phytomelan (even in fleshy fruits, though Dianella bambusifolia may be an exception); black (usually), or brown (e.g., Dianella bambusifolia).

Seedling. Hypocotyl internode present (short). Seedling collar not conspicuous. Cotyledon hyperphyll elongated, or compact; assimilatory (when elongated), or non-assimilatory; more or less circular in t.s. Coleoptile absent. Seedling cataphylls present. First leaf dorsiventral. Primary root persistent.

Physiology, phytochemistry. Not cyanogenic. Anthraquinones detected; polyacetate derived. Proanthocyanidins present (Dianella), or absent (Phormium); when present, cyanidin. Flavonols absent. Ellagic acid absent.

Geography, cytology. Holarctic, Paleotropical, Neotropical, Australian, and Antarctic. Boreal. Southeast Asia, Australia, Pacific Islands, New Zealand, with Dianella extending to Africa, Madasgascar and Mascarene Is. X = 8.

Taxonomy. Subclass Monocotyledonae. Dahlgren et al. Superorder Liliiflorae; Asparagales. APG III core angiosperms; Superorder Lilianae; non-commelinid Monocot. APG IV Order Asparagales (as Asphodelaceae-Hemerocallidoideae).

Species about 30. Genera 7; Agrostocrinum, Corynotheca (or Anthericaceae), Dianella, Excremis, Phormium, Stypandra, Thelionema.

Illustrations. • Phormium tenax: Bot. Mag. 19 (1804). • Floral diagram (Phormium). • Dianella caerulea (Chittenden). • Dianella aff. longifolia: Bot. Reg. 734, 1823. • Dianella strumosa, cf. D. longifolia: Bot. Reg. 751, 1823. • Dianella archeri and D. tasmanica: Hooker, Fl. Tasmaniae (1860).

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: 15th April 2018.’.