Houstonia pusilla Schoepf (redirected from: Houstonia minima)
Family: Rubiaceae
[Hedyotis caerulea var. minima (Beck) Fosberg,  more...]
Houstonia pusilla image
Steven J. Baskauf  

Plant: annual; STEMS 1.5-15(-25) cm tall, slender

Leaves: usually elliptic, ovate, or spatulate, to 25 mm long, 0.5-5(-9) mm wide

Flowers: homostylous, solitary on long erect or nodding pedicels to ca. 4 cm long; corollas 3.5-10(-12.5) mm long, salverform, usually purple or violet with reddish or brownish center

Fruit: FRUITS 1.5-4 mm long, 2.5-6 mm wide, thin walled, 1/2 inferior. SEEDS 0.5-1 mm in diameter, subglobose, with a small orifice opening into a subglobose hilar cavity without a hilar ridge

Misc: Grassy places, fields, in open or forested areas; 1000-1350 m (3300-4400 ft); Apr-May

REFERENCES: Terrell, Edward E. 1995 Rubiaceae. Houstonia. J. Ariz. - Nev. Acad. Sci. 29(l): 36.

Levin 1995, Kearney and Peebles 1969

Duration: Annual

Nativity: Native

Lifeform: Forb/Herb

General: Small herbaceous annual with slender stems, erect and diffusely branching.

Leaves: Leaves elliptic, ovate, or spatulate, opposite.

Flowers: Flowers purple or violet with a reddish-brown center, trumpet-shaped with a narrow throat, to 10 mm long, the corolla with 4 lanceolate lobes, solitary on long pedicels to 4 cm long , the 4 calyx teeth awl-shaped.

Fruits: Capsules thin-walled, to 4 mm long. Seeds subglobose, with a small cup-like cavity that has no ridge within.

Ecology: Found open areas in grasslands, fields, and forests, from 3,300-4,400 ft (1067-1372 m); flowering April-May.

Notes: Look to the solitary flowers borne on long, slender flowers to help identify this species.

Synonyms: None

Editor: LCrumbacher, 2011

Much branched annual 5-15 cm, the stems glabrous; basal lvs ovate to elliptic, 5-10 mm, tapering to a short petiole, scaberulous on the margin; upper lvs narrower, subsessile; fls short-styled, solitary, terminal or also from the upper axils, on peduncles 1-3 cm; sep narrowly oblong to lance-ovate, 1.2-3 mm, half to fully as long as the cor-tube; cor blue or purple with a reddish eye, salverform, the tube 2.5-5 mm, glabrous within, the limb 4-8 mm wide; fr and seeds of no. 7 [Hedyotis caerulea (L.) Hook.]; 2n=16. Dry soil; coastal plain from se. Va. to Tex.; inland from Ill. to Nebr., s. to Tenn. and Tex. Apr. (Houstonia minima; Houstonia patens; Houstonia pusilla)

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.

Houstonia pusilla image
Steven J. Baskauf  
Houstonia pusilla image
Steven J. Baskauf  
Houstonia pusilla image
Steven J. Baskauf  
Houstonia pusilla image
Steven J. Baskauf