SIMPLIFIED IDENTIFICATION KEY FOR FOSSIL DIPTEROCARPACEAE BLUME

This identification key is based on Schweitzer (1958); with additional informations of Anisopteroxylon Ghosh & Kazmi and Hopenium Awasthi from Poole (1993) and Awasthi (1980) respectively.

1. Secretory canals diffuse or in short tangential lines up to 8. Rarely long lines .............................................. 2

— Secretory canals almost always in long tangential lines. Rarely isolated ........................................................ 4

2. Narrow vessels (mean diameter <150 µm) ..................................................................................................... ....................................................................................... Vaterioxylon Trivedi & Misra / Vaticoxylon Schweitzer

— Wide vessels (mean diameter> 150 µm) ..................................................................................................... 3

3. Diffuse and small canals, sheath cells abundant ............................................ Anisopteroxylon Ghosh & Kazmi

— Canals in short lines, solitary vessels ....................................................................... Dipterocarpoxylon Holden

4. Exclusively solitary vessels, fibre-tracheids ......................................................... Dryobalanoxylon Den Berger

— None of these combined ............................................................................................................................. 5

5. Upright or square cells interspaced with procumbent cells ................................................ Hopenium Awasthi

— Only procumbent cells in median portion (or sheath cells) ........................................ Shoreoxylon Den Berger