The Families of Flowering Plants

L. Watson and M. J. Dallwitz


Myoporaceae R. Br.

Including Bontiaceae Horan., Spielmannieae (Spielmanniaceae) J.G. Agardh

Habit and leaf form. Small trees, or shrubs; non-laticiferous and without coloured juice; resinous, or not resinous. Mesophytic, or xerophytic. Leaves deciduous; minute to small (often), or medium-sized; alternate, or opposite to whorled (rarely); usually spiral; often more or less leathery; petiolate to sessile; non-sheathing; gland-dotted (often), or not gland-dotted (Oftia); simple; epulvinate. Lamina entire. Leaves exstipulate. Lamina margins entire, or crenate, or serrate, or dentate. Leaves without a persistent basal meristem.

Leaf anatomy. Lamina isobilateral (nearly always), or dorsiventral (Oftia); with secretory cavities (usually), or without secretory cavities (Oftia). Secretory cavities containing oil, or containing resin. Minor leaf veins without phloem transfer cells (Myoporum).

Stem anatomy. Young stems cylindrical. Secretory cavities present; with resin, or with oil. Cork cambium present; initially superficial. Nodes unilacunar. Primary vascular tissue centrifugal (usually), or bicollateral (Oftia). Internal phloem present (Oftia), or absent. Secondary thickening developing from a conventional cambial ring. Xylem with fibre tracheids. Vessel end-walls simple. Wood storied, or partially storied (VP, VPI); parenchyma paratracheal.

Reproductive type, pollination. Unisexual flowers absent. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’; in cymes. The terminal inflorescence unit cymose. Inflorescences axillary. Flowers ebracteate; small, or medium-sized; regular to very irregular; when irregular, more or less zygomorphic. The floral irregularity involving the androecium, or involving the perianth and involving the androecium (not the calyx). Flowers 5 merous; cyclic; tetracyclic. Floral receptacle with neither androphore nor gynophore. Free hypanthium absent.

Perianth with distinct calyx and corolla; (9–)10; 2 whorled; isomerous (usually), or anisomerous. Calyx (4–)5; 1 whorled; more or less polysepalous (commonly), or gamosepalous; when gamosepalous, blunt-lobed, or toothed; unequal but not bilabiate (sometimes), or regular; persistent (scarious); accrescent, or non-accrescent; basally imbricate, or open in bud; with the median member posterior. Corolla more or less disguisedly 5; 1 whorled; gamopetalous; imbricate; bilabiate (often, more or less), or regular.

Androecium (3–)4, or 5. Androecial members adnate (to the corolla tube); all equal, or markedly unequal (mostly); free of one another; 1 whorled. Androecium exclusively of fertile stamens (the upper, posterior member lacking), or including staminodes. Staminodes when present, 1; in the same series as the fertile stamens; representing the posterior median member. Fertile stamens representing the posterior-lateral pair and the anterior-lateral pair. Stamens (3–)4(–5); usually didynamous; reduced in number relative to the adjacent perianth (nearly always), or isomerous with the perianth (rarely); oppositisepalous; alternating with the corolla members. Anthers connivent, or separate from one another; versatile; dehiscing via longitudinal slits, or dehiscing transversely; introrse; unilocular to bilocular (the cells confluent above). Tapetum glandular. Pollen grains aperturate; 2–4 aperturate; colporate (sometimes with two pores per furrow), or rugate; 2-celled.

Gynoecium 2 carpelled. Carpels reduced in number relative to the perianth. The pistil 2 celled, or 3–8 celled. Gynoecium syncarpous; synstylovarious to eu-syncarpous; superior. Ovary 2 locular (but sometimes with secondary segmentation of the locules). Locules secondarily divided by ‘false septa’, or without ‘false septa’. Gynoecium median; stylate. Styles 1; from a depression at the top of the ovary; apical. Stigmas 1; 1–2 lobed; dry type; papillate; Group II type. Placentation axile, or apical. Ovules (1–)2 per locule (from near the summit), or 4–8 per locule (superposed in pairs), or 1 per locule (per locellus); pendulous; non-arillate; anatropous; unitegmic; tenuinucellate. Endothelium differentiated. Embryo-sac development Polygonum-type. Polar nuclei fusing prior to fertilization. Antipodal cells formed; 3; not proliferating; persistent. Synergids pear-shaped. Endosperm formation cellular. Endosperm haustoria present; chalazal and micropylar. Embryogeny onagrad.

Fruit fleshy to non-fleshy; indehiscent, or a schizocarp. Mericarps when schizocarpic, 2–10 (? — one-seeded); comprising drupelets. Fruit when non-schizocarpic, a drupe. The drupes with separable pyrenes (these one-seeded). Seeds scantily endospermic, or non-endospermic. Cotyledons 2; semi-cylindric. Embryo straight.

Seedling. Germination phanerocotylar.

Physiology, biochemistry. Cyanogenic, or not cyanogenic. Cynogenic constituents phenylalanine-derived. Alkaloids present, or absent. Iridoids detected; ‘Route II’ type (+decarb.). Verbascosides detected (Eremophila). Proanthocyanidins absent. Flavonols absent. Ellagic acid absent (3 species, 2 genera). Saponins/sapogenins present (rarely), or absent. Aluminium accumulation not found.

Peculiar feature. Lamina tip not abaxially pouched.

Geography, cytology. Temperate to tropical. Mainly Australasia and the South Pacific islands, a few in South Africa, Mauritius, Eastern Asia, Hawaii, West Indies. X = 27. Supposed basic chromosome number of family 27.

Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren’s Superorder Lamiiflorae; Scrophulariales. Cronquist’s Subclass Asteridae; Scrophulariales. APG (1998) Eudicot; core Eudicot; Asterid; Euasterid I; Lamiales. Species 90. Genera 4–7; Bontia, Eremophila, Myoporum, Oftia(?), Pholidia, Ranopisoa, Spielmannia (or Scrophulariaceae?).

Illustrations. • Technical details (Myoporum, Stenochilus).


Cite this publication as: ‘L. Watson and M. J. Dallwitz (1992 onwards). The Families of Flowering Plants: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 14th December 2000. http://biodiversity.uno.edu/delta/’. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993, 1995, 2000), and Watson and Dallwitz (1991) should also be cited (see References).

Index