Bonnaya ruelloides (Duckbill Lindernia) was a new plant added to my website recently. It was spotted on 18 September in the early afternoon in a nature park. While the few plants found were bearing fruits (capsules), there was no flower on them. Most likely it was due to the time of the day that I saw it. I went back to the same spot this week in the early part of the morning and got the flower pictures that I was looking for. In addition, I also found another larger population nearby.

This low-lying herbaceous plant was treated as a native species in the 2022 Singapore flora checklist (page 411) and presumed to be nationally extinct (“NEx”) according to the assessment in the publication. The accepted botanical name used in the checklist was Lindernia ruelloides, a synonym of Bonnaya ruelloides as indicated in the Plants of the World Online (POWO) website.

In the older Singapore flora checklist published in 2009, the accepted botanical name used was Lindernia ruellioides (with an extra “i”) and assessed to be a “weed of uncertain origin”. A flora survey done at Sisters’ Islands and reported in 2017 [1] had listed this species. The table in Appendix 2 of the article indicated that specimen of this plant was available at the herbarium of the National University of Singapore. A check on Bonnaya ruelloides in the iNaturalist website on 29 September 2024 yielded 3 observations from Singapore; one was reported in 2022 while 2 were reported in 2023. In conclusion, Bonnaya ruelloides had not extinct in Singapore yet.

This plant is from the family Linderniaceae. So far, I had collected the pictures of 8 of the members found in Singapore. The last time I added a new member (Yamazakia viscosa) in this family was in September 2020.

Except for Torenia fournieri, the accepted botanical names used in my website were not the same as the ones used in the 2022 Singapore flora checklist (page 409-412). In general, I followed the naming system used by the POWO website. The table below illustrated the differences among the 2 checklists and the 2 most referenced websites in the plant world.

Two of the species, Lindernia rotundifolia (Roundleaf Lindernia) and Vandellia diffusa (Spreading False Pimpernel), that I spotted years back in Singapore in 2013 and 2012 respectively were not listed in the both the 2022 and 2009 Singapore flora checklists. In the iNaturalist website (viewed on 29 September 2024), the observation records for these 2 species from Singapore were 17 and 19 respectively. Moreover, Lindernia rotundifolia was displayed in NParks Flora & Fauna Web.

References:

[1] Hung SMX, Chong KY, Yee ATK, Lim RCJ, Loh JW, Neo L, Seah WW, Tan SY, Teo AXY, Tun K, Tong CHY, Koh KS, Tan HTW.The vascular plant flora and vegetation of the islands associated with Singapore’s first Marine Park (I): The Sisters’ Islands. Nature In Singapore 2017;10:7-24. | Read article |