Sunday, October 15, 2023

[Botany • 2023] Burttianthus rejangicus & B. solus (Araceae) • Two New Species from Sarawak, Malaysian Borneo [Schismatoglottideae of Borneo LXXVI]


Burttianthus rejangicus S.Y.Wong, M.Lo & P.C.Boyce, 

in Wong, Lo et Boyce, 2023. 
  facebook.com: Michael Lo

Abstract
Two new species of Burttianthus are described from Sarawak: B. rejangicus from the Rejang and Balleh rivers of the western Rejang Basin, and B. solus from the Similajau Basin, Bintulu. Both novelties are illustrated from living plants and the spadices of eight of the nine Burttianthus species are compared in accompanying figures.

Keywords: Araceae, Burttianthus, Malaysia, Kapit Division, Bintulu Division, Borneo



Burttianthus rejangicus S.Y.Wong, M.Lo & P.C.Boyce, sp. nov.

Diagnosis: Burttianthus rejangicus is unique by the fusiform pistillate floret zone narrower than the staminate floret zone, the almost inflated rims to the stamens, and by the dull pale green stigmas with a central depression.

Etymology: From Rejang, plus Greek -ikos [-icos], indicating belonging to

Distribution: Known only from the Rejang and Balleh rivers of the western Rejang basin where the small populations are widely scattered.


Burttianthus solus S.Y.Wong, M. Lo & P.C.Boyce.
A. Plants in habitat. B. Bloom during pistillate anthesis. C. Bloom at pistillate anthesis, nearside spathe artificially removed. D. Bloom at onset of staminate anthesis, spathe limb beginning to shed. E. Lower persistent splash-cup spathe with the fruits decomposing and seed beginning to germinate.
 Photos: P.C.Boyce.


Burttianthus solus S.Y.Wong, M.Lo & P.C.Boyce, sp. nov.
 
Diagnosis: Burttianthus solus is distinguished from all other species by the pistillate and staminate zones of florets separated by a naked interstice, and further by the lax (not congested) pistillate florets.

Etymology: Latin, sōlus (feminine sōla, neuter sōlum); alone, sole, only, by oneself with no others around – in allusion to the separation of the pistillate and staminate zones, and the laxly arranged pistillate florets.



Sin Yeng Wong, Michael Lo and Peter C. Boyce. 2023. Schismatoglottideae (Araceae) of Borneo LXXVI — Two new Burttianthus species from Sarawak. Webbia. 78(2); 123-129. DOI: 10.36253/jopt-15209  oaj.fupress.net/index.php/Webbia/article/view/15209