Brachyscias J.M.Hart & Henwood

Scientific Description

Family Apiaceae.

Formerly known by the phrase name Genus sp. Shannon.

Habit and leaf form. Minute, moss-like herbs; bearing essential oils, or without essential oils (?); resinous, or not resinous (?). Annual; to 0.012–0.022 m high. Helophytic, or mesophytic. Leaves small; clustered near base of stems; ‘herbaceous’; petiolate; gland-dotted, or not gland-dotted (?); aromatic, or foetid, or without marked odour (?); simple; pulvinate, or epulvinate (?). Leaf blades entire, or dissected; when entire, linear; when dissected, divided into 3 linear segments; pinnately veined, or palmately veined, or parallel-veined (?). Leaves with stipules, or without stipules (?); without a persistent basal meristem. Stem anatomy. Nodes multilacunar, or tri-lacunar (?). Secondary thickening developing from a conventional cambial ring, or anomalous (?); from a single cambial ring.

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

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in umbels. Inflorescences compound. The terminal inflorescence unit cymose, or racemose (?). Inflorescences terminal; irregular, not exceeding the leaves; with involucral bracts, or without involucral bracts (?); pseudanthial, or not pseudanthial (?). Flowers pedicellate; bracteate. Bracts leaf-like, entire. Flowers small; regular to somewhat irregular (?); 5 merous (except for the gynoecium); cyclic; tricyclic. Free hypanthium absent. Perianth petaline; 5; 1 -whorled; white. Corolla 5; 1 -whorled; polypetalous; valvate; unequal but not bilabiate, or regular; white. Androecium 5. Androecial members free of the perianth; all equal to markedly unequal (?); free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens 5; isomerous with the perianth; oppositisepalous; inflexed in bud. Anthers dehiscing via longitudinal slits; introrse; tetrasporangiate. Gynoecium 2 carpelled. The pistil 2 celled. Gynoecium syncarpous; synovarious; inferior. Ovary plurilocular; 2 locular. Gynoecium median. Epigynous disk present. Gynoecium stylate. Styles 2; free to partially joined (?); apical. Stigmas wet type; non-papillate; Group IV type. Placentation axile, or apical (?). Ovules 1 per locule, or 2 per locule (usually two, but one abortive ?); pendulous; epitropous; non-arillate; anatropous.

Fruit and seed features. Fruit non-fleshy; a schizocarp. Mericarps 2. Seeds endospermic. Endosperm oily. Embryo well differentiated. Cotyledons 2. Embryo achlorophyllous; straight. Seedling. Germination phanerocotylar.

Physiology, biochemistry. Aluminium accumulation not found. Photosynthetic pathway: C₃.

Geography, cytology, number of species. Native of Australia. Endemic to Australia. A genus of 1 species; 1 species in Western Australia; 1 endemic to Western Australia.