Oldenlandia corymbosa
(flat-top mille graines)

Preferred Common Name

• flat-top mille graines

Other Scientific Names

• Gerontogea biflora Cham. & Schltdl.
• Gerontogea corymbosa (L.) Cham. & Schltdl.
• Gerontogea herbacea Cham. & Schltdl.
• Hedyotis burmanniana Wight & Arn.
• Hedyotis corymbosa (L.) Lam.
• Hedyotis depressa (Willd.) Roem. & Schult.
• Hedyotis diantha Schult.
• Hedyotis graminicola Kurz
• Hedyotis intermedia Wight & Arn.
• Hedyotis pseudocorymbosa Bakh.f.
• Hedyotis pusilla Hochst. ex A.Rich.
• Hedyotis ramosa (Roxb.) Blume
• Hedyotis scabrida Steud.
• Hedyotis sperguloides A.Rich.
• Oldenlandia alsinifolia G.Don
• Oldenlandia burmanniana G.Don
• Oldenlandia capillaris DC.
• Oldenlandia depressa Willd.
• Oldenlandia mollugoides O.Schwarz
• Oldenlandia praetermissa Bremek.
• Oldenlandia pseudocorymbosa (Bakh.f.) Raizada
• Oldenlandia ramosa Roxb.
• Oldenlandia scabrida DC.

International Common Names

• English: old world diamond-flower
• French: mille-grainers
• Chinese: san fang hua er cao

Local Common Names

• El Salvador: hierba de corral
• India: daman papra; diamond flower; parpata; parpataka; pitpappar; wild chayroot
• Indonesia: parpatah; parpatakah
• Madagascar: ahibitsiki
• Malaysia: parpatakam; parpatakapullu; pokok telur belangkas; siku dengan; siku-siku
• Philippines: malaulasiman; ulasimanaso
• Thailand: yaa linnguu

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Gentianales
•                         Family: Rubiaceae
•                             Genus: Oldenlandia
•                                 Species: Oldenlandia corymbosa

The family Rubiaceae comprises 611 genera and about 13,150 species distributed worldwide, but with most species located in tropical regions. This family is particularly diverse in Madagascar and the Andes (Davis et al., 2009; Stevens, 2017). Oldenlandia and Hedyotis are two of the largest genera within the Rubiaceae and are commonly grouped as the Hedyotis-Oldenlandia complex. This complex contains approximately 500–600 species occurring throughout tropical and subtropical regions worldwide. Species within this complex are very similar and share a herbaceous or shrubby habit with relatively small, mostly 4-merous flowers, bilobed stigmas, and dry, two-celled capsular fruits (Sivarajan and Biju, 1990; Neupane et al., 2009; Guo et al., 2013).

Due to the broad geographic distribution, species richness and morphological diversity, the generic delimitation in the Hedyotis–Oldenlandia complex has a long taxonomically confused history. Previous systematic treatments have varied from accepting a very broad-sensed Hedyotis, to partially or completely segregating these two taxa into different numbers of smaller genera (Guo et al., 2013; Wikström et al., 2013; Neupane et al., 2015; Hsu and Chen, 2017).

The following description is from Flora of China Editorial Committee (2018): Slender herb, annual, to 40 cm tall; stems 4-angled to flattened, 2-sulcate, with sides glabrous and angles thickened to winged and puberulent and/or scaberulous or terete to flattened and sparsely to densely scaberulous to puberulent throughout. Leaves subsessile; blade drying membranous, linear, narrowly lanceolate, or narrowly elliptic, 0.8-2 × 0.1-0.5 cm, adaxially sparsely scaberulous to glabrescent, abaxially glabrescent, base cuneate to acute, margins usually at least shortly revolute when dry, apex acute; secondary veins not visible; stipules fused to petiole bases, tubular, 1-2 mm, puberulent to glabrous, rounded to triangular, with 1-5(or 7) linear lobes or bristles 0.2-2.5 mm, these sometimes bifid. Inflorescence axillary, 1-flowered or usually cymose and 2-5-flowered, glabrous, pedunculate; peduncles 1(or 2) per axil, filiform, 1-16 mm; bracts lacking or stipuliform and 1-1.2 mm; pedicels slender, 2-12 mm. Flowers homostylous, pedicellate. Calyx glabrous to puberulent; hypanthium portion subglobose to narrowly ellipsoid, 0.5-0.8 mm; limb lobed essentially to base; lobes narrowly triangular, 0.5-1.2 mm, entire to ciliate. Corolla white or pink, funnelform to rotate; tube 0.8-1 mm, inside pubescent or glabrous; lobes spatulate-oblong to narrowly triangular, 0.5-0.8 mm. Anthers included, ca. 0.6 mm. Stigma 0.3-0.5 mm, included. Fruit capsular, subglobose, ovoid, or oblate, 1.2-2 × 1.2-2.2 mm; seeds 20 or more, dark brown.

Soil drainage

• seasonally waterlogged

Soil reaction

• acid
• neutral

Soil texture

• heavy
• light
• medium

Oldenlandia corymbosa spreads mainly by seed, but plants can sometimes root at the nodes. The species produces numerous tiny seeds (~0.25 mm length) that can be easily dispersed by animals, water, vehicles, and in contaminated soil and agricultural produce. Stem and root fragments can be broken off and spread during cultivation or road maintenance, and can also be dispersed in contaminated soil (Wagner et al., 1999; Fern, 2014; Flora of China Editorial Committee, 2018; PIER, 2018; PROSEA, 2018; PROTA, 2018).

Oldenlandia corymbosa is a weed in cassava, pineapple, maize, soybean and rice plantations (Olorunmaiye and Olorunmaiye, 2008; Habimana et al., 2013; Flora of China Editorial Committee, 2018; PROSEA, 2018) and also in lawn areas in parks and gardens (Shahid and Rao, 2014).

Oldenlandia corymbosa is a cosmopolitan weed that often invades forest edges, disturbed areas, riversides, foreshores, lowland forests, coastal thickets and grasslands. Under suitable environmental conditions, it can rapidly dominate an ecosystem, with the potential to displace and outcompete native plants at early successional stages in disturbed areas. It has also been listed as a common weed in Biscayne National Park in Florida, USA (Wagner et al., 1999; Khuroo et al., 2012; GRIIS, 2018; National Park Service, 2018; PIER, 2018; PROTA, 2018).

• Proved invasive outside its native range
• Abundant in its native range
• Highly adaptable to different environments
• Is a habitat generalist
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Pioneering in disturbed areas
• Highly mobile locally
• Benefits from human association (i.e. it is a human commensal)
• Long lived
• Fast growing
• Gregarious

• Damaged ecosystem services
• Ecosystem change/ habitat alteration
• Modification of successional patterns
• Negatively impacts agriculture
• Reduced native biodiversity

• Competition - monopolizing resources
• Competition - smothering
• Rapid growth
• Rooting

• Highly likely to be transported internationally accidentally
• Difficult to identify/detect as a commodity contaminant
• Difficult to identify/detect in the field

Oldenlandia corymbosa is a common medicinal herb across tropical Asia. In Indo-China, it is also used as antirheumatic. In India, the plant is a common ingredient in mixtures used to treat fever and as a tonic. It is also used to treat jaundice. The roots are reported to have vermifuge properties (PROSEA, 2018). In Chinese folk medicine, the plant is used to treat skin sores, ulcers, sore throat, bronchitis, gynecological infections and pelvic inflammatory diseases. The plant contains flavonols, phenolic acids, anthocyanidins, irridoids and alkaloids. In India, it is used to produce natural dyes (Patel et al., 2014; PROTA, 2018).