Tuesday, August 27, 2019

[Botany • 2019] Diastema fimbratiloba (Gesneriaceae) • A New Species of Diastema from the eastern Andean Slopes of Peru


Diastema fimbratiloba Moonlight & J.L.Clark

in Clark & Moonlight, 2019. 

Abstract
striking new species of DiastemaD. fimbratiloba, is described from Ucayali Region, along the eastern Andean slopes in central Peru. The new species has a fimbriate lower corolla lobe, a feature not previously documented in the genus. We also provide a general comparison of the newly described species and morphologically related species in the context of the taxonomy and phylogeny of the poorly known genus Diastema.

Keywords: Diastema, Gesneriaceae, Peru.


Diastema fimbratiloba Moonlight & J.L.Clark, sp. nov.
Photograph taken by P. W. Moonlight 
of the type collection in the field.

Diastema fimbratiloba Moonlight & J.L. Clark, sp. nov.
 A, Habit; B, dissected corolla tube, showing the androecium; C, abaxial view of the calyx lobes; D, gynoecium, side view; E, nectary and base of the gynoecium, side view; F, stigma, side view; G, anthers, bottom view. Scale bars: A, 3 cm; B–D, 6 mm; E–G, 3 mm. Illustration by C. Banks from the type collection.

Diastema fimbratiloba Moonlight & J.L.Clark, sp. nov. 


Etymology. The species is named for the distinctive fimbriations on the lower corolla lobe. Fimbriations are common in several genera of New World Gesneriaceae (especially Drymonia Mart.), but no currently known described species in Diastema is known for this feature. It is possible that other species of Diastema have fimbriate corolla margins (cf. note above regarding the population without collection from Atalaya, Peru), but this is a difficult character to evaluate from collections, because the flowers are delicate and ephemeral. As a result, corolla features in Diastema are not readily available on most herbarium specimens.



J. L. Clark and P. W. Moonlight. 2019. A New Species of Diastema (Gesneriaceae) from the eastern Andean Slopes of Peru. Edinburgh Journal of Botany: An International Journal of Plant Systematics and Biodiversity. DOI:  10.1017/S0960428619000192