Trematolobelia wimmeri O. Deg. & I. Deg.

Genus: Trematolobelia

Range: Hawai'i; windward side from Kohala to Kīlauea; wet forest, 610-1,400 m. Note USGS map shows the old circumscription of T. grandifolia that included T. wimmeri.

Growth form: Treelet, 1-4 m tall.

This species ...

How to identify: T. wimmeri and T. grandifolia overlap in the Kohala mountains. T. wimmeri has smaller yellow-green corolla (5.4-6.7 cm long) on pubescent racemes subtended by narrow leaves 7-19 times longer than wide. T. grandifolia has larger, white corollas 6.5-7.5 cm long on glabrous racemes subtended by broad leaves, only 4 to 6 times longer than wide. My examination of various specimens in the Bishop Museum show that the leaf length/width ratio is imperfect and any specimen with a ratio between 5 and 8 cannot reliably be identified by this trait alone.

Images:

Sources:

• Hillebrand, 1888 (lists Lobelia macrostachys as occurring in Hawaii with narrow leaves and pink corollas);
• Not Rock, 1913 or Rock, 1919 (Rock notes white corollas which indicate var. grandifolia not var. wimmeri; also Hosmer's specimen is an isotype of Tr. grandifolia);
• Degener, 1934 (as Trematolobelia sandwicensis, in part: species from the big island);
• Wimmer, 1953 (as Trematolobelia macrostachys, in part: species from the big island);
• Wagner et al., 1990 (as part of Trematolobelia grandifolia);
• Lammers, 2009.