Citation: L., Sp. Pl. 570 (1753).

Synonymy: Not Applicable

Common name: Horehound.

Description:
Perennial shrubs to 60 cm high, much-branched mainly from the base with branches usually quadrangular but usually obscured by a woolly to villous cover of long stellately branched hairs becoming woody at the base; leaves with the petiole 0.2-3.5 cm long; blade ovate, rhombic-ovate to orbicular, 1-3.5 x 0.8-3 cm, more or less deeply dentate to dentate-serrate, reticulate-crinkled, hairy to subglabrous above, villous below.

Inflorescence a thyrse without a distinct peduncle, with sessile cymose part-inflorescences usually with many flowers and subtended by leaf-like bracts, becoming shorter towards the apex; sepals almost completely connate, 10-veined, 4-7 mm long, woolly, ending in 10 glabrous hooked spines; corolla white, funnel-shaped, with tube about half its length, zygomorphic, strongly 2-lipped, 6-12 mm long, hairy outside and on the inside of the posterior lip, with posterior lip with 2 narrow straight lobes, with anterior lip spathulate, divided into 2 narrow lateral ones and the broadly spathulate central one often with an undulate margin; stamens inserted at about the middle of the corolla tube, with filaments longer than the anther, bulging at the base and with a tuft of hairs; anthers oblong in surface view, glabrous, included; ovary on a thick disc, deeply 4-lobed, with a slender style inserted near the base, with a 2-fid stigma included.

Mericarps oblong-obovoid, c. 2 mm long, truncate, slightly centripetally compressed and triangular in section, usually with sharply keeled margins, with the attachment scar at the base of the inside keel, irregularly pusticulate.

	Flowering branch and calyx.
Image source: fig. 553I in Jessop J.P. & Toelken H.R. (Ed.) 1986. Flora of South Australia (4th edn).

Published illustration: Parsons (1973) Noxious weeds of Victoria, figs 170-173; Ross-Craig (1967) Drawings Brit. Pl. 24:pl. 25.

Distribution:  S.Aust.: NU, GT, FR, EA, EP, NL, MU, YP, SL, KI, SE.   All States except the N.T.   New Zealand. Native to most parts of Europe. Conservation status: naturalised Flowering time: July — Dec., but if conditions favourable more or less continuous.

SA Distribution Map based on current data relating to specimens held in the State Herbarium of South Australia

Biology: No text

Author: Not yet available