Monographs Details: Trematolobelia grandifolia (Rock) O.Deg.
Authority: Lammers, Thomas G. Revision of the Endemic Hawaiian genus Trematolobelia (Campanulaceae: Lobelioideae), 61: 126-143.
Family:Campanulaceae
Discussion:

Type: Hawaiian Islands. Hawai'i: Kohala Mts., 4200 ft., Oct 1909, leg. R. S. Hosmer, J. E Rock 6090 (holotype: BISH; isotypes: A, BISH[3], GH). The GH isotype is a mixed gathering; a raceme of Tremato- lobelia wimmeri is mounted on the same sheet (see below). A sheet of Hosmer s.n. at US with the same label data is interpreted as an unnumbered isotype

I previously (Lammers, 1990) circumscribed this species more broadly , including within it nearly all specimens of Trematolobelia from Hawai'i. As such, T. grandifolia was extremely variable in leaf shape and size, flower size and color, and pubescence of the inflorescence. In the present study, I realized that nearly all of the speciments from Hawai'i acutally fall into two distinct morphological groups. The first, which includes the type of T. grandifolia, is restricted to the Kohala Mountains of northwestern Hawai'i and is characterized by broadly oblanceolate or oblong leaves only 4.3 -6.2 times longer than wide, glabrous racemes, and white corollas 65- 75 mm long. The second group is sympatric with T. grandifolia in the Kohala Mountains, but also occurs eastward and southward in South Hilo, Puna, and Ka'ΓΌ Districts. It differs in bearing oblanceolate, narrowly oblong, or linear leaves 7-19 times longer than wide, pubescent racemes, and yellowish green corollas suffused or streaked with pink that are 54- 67 mm long.

My original decision to identify all these plants as Trematolobelia grandifolia was occasioned by a pair of specimens from the Kohala Mountains {Degener et al 20044, DS, W; Rock 6090, GH) in which mature fruiting racemes from dead or dying (and hence leafless) plants were added to flowering (leafy) specimens, creating a sheet on which one inflorescence was glabrous and the other pubescent. This created the mistaken impres- sion that pubescence varies within a popula- tion, and that leaf and corolla features thus are extremely variable. It was these two mixed collections that were responsible for the erroneous description of T. grandifolia as having racemes "glabrous or pubescent" by both myself (Lammers, 1990) and St. John (1983). By considering only those organs on a sheet that were physically attached to one another, it is now clear that glabrous racemes always produce larger white corollas and are subtended by relatively broad leaves, while pubescent racemes always bear smaller yel- lowish green corollas suffused or streaked with pink and are subtended by relatively narrow leaves. I have seen no genuinely intermediate specimens from the area of sympatry, which suggests that the two groups are reproductively isolated and merit specific rank

There is a fragmentary sheet ('Hawaii Natl. Park," 28 Aug 1961, B. Templeton s.n. LAM) that may be referable here. The racemes are glabrous as in T. granidifolia, and the leaves are of the same general shap, but smaller (just 8.5 -10 cm long x 2.3- 2.6cm wide vs. 16-32 cm x 2.7 -6 cm), relatively wider (just 3.3 4.3 times longer than wide vs. 4.3 - 6.2 times), and acute (vs. obtuse) at apex. Unfortunatly, the flowers are mere buds, precluding a complete comparison