The Families of Flowering Plants

L. Watson and M. J. Dallwitz


Achatocarpaceae Heimerl.

~ Phytolaccaceae

Habit and leaf form. Small trees, or shrubs (the branchlets sometimes spiny). Plants non-succulent. Leptocaul. Leaves alternate; spiral; non-sheathing; simple. Lamina entire; pinnately veined; cross-venulate. Leaves exstipulate. Lamina margins entire.

Stem anatomy. Internal phloem absent. Secondary thickening developing from a conventional cambial ring. ‘Included’ phloem absent. Xylem with vessels. Vessel end-walls simple. Sieve-tube plastids P-type; type III (a).

Reproductive type, pollination. Plants dioecious. Female flowers without staminodes. Gynoecium of male flowers absent.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes, or in racemes, or in fascicles, or in panicles. The terminal inflorescence unit cymose. Inflorescences small, branched cymes, racemes, panicles or fascicles. Flowers bracteate; small. Free hypanthium absent.

Perianth sepaline; 4, or 5; 1 whorled; green. Calyx 4, or 5; 1 whorled; polysepalous; regular; persistent; imbricate.

Androecium in male flowers, 10–20. Androecial members free of the perianth; coherent (basally connate); 1 adelphous. Androecium exclusively of fertile stamens. Stamens 10–20. Anthers basifixed (elongate-oblong); non-versatile; dehiscing via longitudinal slits; extrorse. Pollen grains aperturate (the apertures poorly defined, irregular in shape and distribution); 4–7 aperturate; foraminate, or rugate, or colpate (Phaulothamnus); spinulose.

Gynoecium 2 carpelled. Carpels reduced in number relative to the perianth. The pistil 1 celled. Gynoecium syncarpous; synovarious (the styles simple, divergent, uncinate); superior. Ovary 1 locular. Gynoecium stylate. Styles 2. Stigmas 2. Placentation basal. Ovules in the single cavity 1; funicled; ascending; non-arillate; campylotropous.

Fruit fleshy; indehiscent; a berry. Dispersal unit the fruit. Fruit 1 seeded. Seeds (strictly) non-endospermic. Perisperm present (copious, mealy). Embryo well differentiated. Cotyledons 2. Embryo curved.

Physiology, biochemistry. Ellagic acid absent.

Geography, cytology. Sub-tropical to tropical. Warm America.

Taxonomy. Subclass Dicotyledonae; Crassinucelli. Dahlgren’s Superorder Caryophylliflorae; Caryophyllales. Cronquist’s Subclass Caryophyllidae; Caryophyllales. APG (1998) Eudicot; core Eudicot; neither Rosid nor Asterid; Caryophyllales. Species 10. Genera 2; Achatocarpus, Phaulothamnus.

Illustrations. • Technical details.


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