Taxonomic uncertainty of Stachytarpheta (Verbenaceae) in the Asia-Pacific and implications for invasive weed recognition and management (vol 16, pg 83, 2014)

Stachytarpheta indica has been regarded as an agricultural weed occurring throughout south-east Asia. In Australia, it is classified as an invasive weed by the Northern Australia Quarantine Strategy (NAQS) (Brown et al. 2008). After examining several papers from the 1990s, we conclude that there is no evidence to support S. indica being in this region and that the name has been historically misapplied to several other species of Stachytarpheta. We recommend its removal from the NAQS invasive weed target list. A table of morphological characters is provided for four species of Stachytarpheta showing major differences in several character and highlights the confusion still surrounding some of the species. Stachytarpheta cayennensis should be added to the flora of Christmas Island, whereas the taxonomic status of S. urticifolia needs to be examined in further detail.