Family Grubbiaceae

Grubbiaceae Endl.

Including Ophiraceae Reichb., Ophiriaceae Arn.

Habit and leaf form. Ericoid shrubs. Xerophytic. Leaves opposite (decussate); rolled; leathery; simple. Lamina entire; linear, or lanceolate. Leaves exstipulate (but the opposite bases connected on either side by transverse ridges). Lamina margins strongly revolute.

Leaf anatomy. Stomata present; anomocytic.

Lamina dorsiventral.

Stem anatomy. Cork cambium present; initially superficial. Nodes tri-lacunar. Secondary thickening developing from a conventional cambial ring. Xylem with tracheids; with vessels. Vessel end-walls oblique; scalariform. Wood parenchyma scanty, diffuse.

Root anatomy. Lateral roots without a conspicuous endodermis.

Reproductive type, pollination. Plants hermaphrodite.

Inflorescence, floral, fruit and seed morphology. Flowers aggregated in ‘inflorescences’; in cymes. The fruiting inflorescences conelike. The ultimate inflorescence unit cymose. Inflorescences axillary; small, axillary, often villous 3-flowered dichasia, or many-flowered compound dichasia. Flowers bracteate; minute (sessile); regular; cyclic. Free hypanthium absent.

Perianth sepaline (apetalous according to Cronquist 1981); 4 (cf. Cronquist, but interpreted by Fagerlind (1947) as K2 bracteiform plus 2 vestigial, C 2+2 diagonally disposed and valvate); 1 whorled, or 4 whorled (depending on interpretation). Calyx 4 (by either interpretation, as applied to the calyx of Cronquist or the corolla of Fagerlind); 1 whorled (Cronquist), or 2 whorled (under Fagerlind’s interpretation); polysepalous (small); valvate.

Androecium 8. Androecial members free of the perianth and adnate (the antesepalous members slightly adnate to the base of the sepals); markedly unequal (the antesepalous members somewhat longer); free of one another; 2 whorled. Androecium exclusively of fertile stamens. Stamens 8; diplostemonous; alternisepalous (if the ostensible calyx is actually corolla, cf. Fagerlind), or oppositisepalous; filantherous (liguliform, laterally compressed). Anthers adnate (to the distal part of the filament); becoming inverted during development, their morphological bases ostensibly apical in the mature stamens; dehiscing via longitudinal slits; ostensibly extrorse (as a result of ontogenetic inversion). Pollen shed as single grains. Pollen grains aperturate; 3 aperturate; colporate.

Gynoecium 2 carpelled. Carpels isomerous with the perianth. The pistil 1 celled, or 2 celled. Gynoecium syncarpous; eu-syncarpous; inferior. Ovary 2 locular (at least initially, but with an ephemeral partition, and subsequently becoming unilocular). Epigynous disk present (annular, hairy). Gynoecium stylate. Styles 1; apical. Stigmas 1; 1 lobed, or 2 lobed. Placentation apical. Ovules 1 per locule; pendulous; anatropous; unitegmic; tenuinucellate. Endothelium differentiated. Embryo-sac development Polygonum-type. Endosperm formation cellular. Endosperm haustoria present; chalazal and micropylar.

Fruit non-fleshy; dehiscent; achene-like, or a drupe. Gynoecia of adjoining flowers combining to form a multiple fruit (the compact cluster representing each inflorescence resembling a cupressaceous cone). The multiple fruits more or less coalescing. Dispersal unit the inflorescence. Fruit (the true fruit) 1 seeded. Seeds endospermic. Endosperm oily. Cotyledons 2. Embryo straight (long, cylindrical).

Physiology, biochemistry. Iridoids not detected.

Geography, cytology. Cape. Temperate to sub-tropical. South Africa.

Taxonomy. Subclass Dicotyledonae; Tenuinucelli (?). Dahlgren’s Superorder Rosiflorae; Cunoniales (?). Cronquist’s Subclass Dilleniidae; Ericales. APG 3 core angiosperms; core eudicot; Superorder Asteranae; Order Cornales.

Species 5. Genera 2; only genera, Grubbia, Strobilocarpus.

Not yet seen: Fagerlind (1947). Sv. Bot. Tidskr. 41, 315–320.