Citation: L., Sp. Pl. 338 (1753).

Derivation: Greek treis, three; glochis, a point, alluding to the points of the carpels.

Synonymy: Not Applicable

Common name: Arrowgrasses.

Description:
Annuals or perennials, occurring in areas periodically or permanently marshy (fresh or salt).

Biology: No bulbous species occur in Australia.

Taxonomic notes: Rauschert (1974) Reprium nov. Spec. Regni veg. 85:654 is followed in treating Triglochin as neuter. As flowers are rarely collected and fruits are needed for identification, fruiting times are given.

Key to Species:

1. Aquatic freshwater perennials, with thick rhizomes (c. 8 mm); leaves to 2 m long; fertile carpels (in S.Aust.) usually 6; fruits c. 10 mm long	T. procerum 7.
1. Annuals or perennials of marshy places; leaves to 30 cm long; fertile carpels 3
2. Carpels 3, all fertile; fruits c. 4 mm long, conical at the apex	T. turriferum 10.
2. Carpels 6, 3 fertile alternating with 3 sterile
3. Fruit without hooks, spurs or wings
4. Perennials with fine (c. 1 mm thick) rhizomes; sterile carpels conspicuous	T. striatum 8.
4. Annuals; sterile carpels not well developed
5. Racemes loose; fruit c. 2 mm long	T. muelleri 5.
5. Racemes dense; fruit c. 1 mm long	T. ovoideum 6.
3. Fruit with wings, spurs or hooks
6. Fertile carpels each with 2 papery wings (so fruit has 6 wings)	T. hexagonum 3.
6. Fertile carpels without wings, but with hooks or spurs
7. Fertile carpels with conspicuous spreading tips, bases with-out hooks or spurs	T. mucronatum 4.
7. Fertile carpels with minute erect tips, bases with hooks or spurs
8. Fruits 5-6 mm long, basal spurs conspicuous and strongly recurved	T. calcitrapum 1.
8. Fruits 2-5 mm long, basal spurs short, either spreading or deflexed
9. Fruit pyramidal, 3-5 mm long	T. centrocarpum 2.
9. Fruit subellipsoid, 2-2.5 mm long	T. trichophorum 9.

Author: Not yet available