Dolichostachys elongata Benoist, 2022

Manzitto-Tripp, Erin A., Darbyshire, Iain, Daniel, Lucinda A. McDade Thomas F. & Kiel, Carrie A., 2022, Revised classification of Acanthaceae and worldwide dichotomous keys, TAXON 71 (1), pp. 103-153 : 141-142

Dolichostachys elongata Benoist , sp. nov. – Holotype: Mada-

gascar: Fénérive, fl. 1912, Perrier de la Bâthie 9448 (P [P00089215]*).

Validating description in Bull. Soc. Bot. France 109: 133. 1962.

Additional material seen. – Madagascar, R. Mananara , fl. Aug. 1912, Perrier de la Bâthie 9445 ( P [ P00089214 ]*).

Notes. – When describing Dolichostachys elongata, Benoist (1962) cited the two specimens listed above but did not designate a type specimen, thus the names of the genus and species were not validly published under Art. 40 of the Code ( Turland & al., 2018). This is rectified here by selection of a type specimen. As Benoist provided full descriptions for the genus and species (in Latin), the names can continue to be attributed to him but with priority from the present publication.

Dolichostachys remains unplaced within Justicieae . The combination of an androecium comprising two stamens with parallel thecae and (apparently) lacking staminodes, a 2-lipped corolla with the lower lip deeply divided into 3 lobes and lacking raised venation in the throat, and a slender spiciform inflorescence suggests possible affinity to Tetrameriinae, but Isoglossinae cannot be ruled out. Benoist (1962) described the pollen as spherical and smooth with three pores. Triporate pollen is observed in some Isoglossinae, notably in Brachystephanus ( Champluvier & Darbyshire, 2009) , but in those cases the grains are still conspicuously “girdled” as in other Isoglossinae. It is possible that Benoist misinterpreted this pollen type.