| Collector | Larsen, K. |
| Number | 42470 |
| Collected with | S. S. Larsen, C. Niyomdham, W. Ueachirakan & P. Sirirugsa. |
| Country | Thailand |
| Subpart | SONGKHLA |
| County | |
| Locality | Tham Ru Nok Sak w of Saba Yoi |
| Coordinates | 6° 35' N 100° 50' E |
| Minimum elevation (m) | 100 |
| Maximum elevation (m) | 100 |
| Start date | 1991/10/21 |
| End date | 1991/10/21 |
| Family | Acanthaceae |
| Identification | Justicia ptychostoma Nees |
| Determined by | K.Rueangsawang |
| Identification qualifier | |
| Field notes | Covering large areas in clearing along limestone cave. Flowers greenish with violet-pink spots on lip. Alc. |
|