颈果草属 jing guo cao shu

Herbs annual. Flowers solitary, axillary. Calyx 5-parted nearly to base; lobes lanceolate, slightly elongated in fruit. Corolla campanulate-tubular; tube somewhat longer than limb; limb 5-parted; lobes overlapping, suborbicular, with small appendages. Stamens inserted at middle of corolla tube, included; anthers ovate-triangular; filaments short. Ovary 4-parted. Style reaching middle of corolla; stigma depressed globose. Gynobase flat. Nutlets 4, horizontally rotate spreading from gynobase, dorsiventrally compressed, ovoid, marginal rib with triangular glochids, margin with smaller glochids; large prickles confluent into a broad wing; attachment scar apical.

One species: endemic to China.

Flower construction, nutlet morphology, and marginal glochids indicate that Metaeritrichium is closely related to Eritrichium, but it differs in having a flat gynobase and rotate-spreading nutlets with apical attachment scars. The gynobase, habit, and pollen grain morphology are similar to those of Microula, but Metaeritrichium differs in having nutlets with prickly marginal ribs and apical attachment scar.

Lower Taxon

• Metaeritrichium microuloides W. T. Wang