Monographs Details: Hackelia bella (J.F.Macbr.) I.M.Johnst.
Authority: Gentry, Johnnie L. & Carr, Robert L. 1976. A revision of the genus Hackelia (Boraginaceae) in North America north of Mexico. Mem. New York Bot. Gard. 26: 121-227.
Description:Species Description - Stout perennial, 5-7 dm tall; stems several from a woody, often much branched caudex, erect, antrorosely strigose in inflorescence, mostly spreading puberulent or sometimes with subappressed hairs below, to nearly tomentose. Radical leaves very many, 15-26 cm long, 22-45 mm wide, elliptic, obtuse, often minutely apiculate, petiolate to not quite ½ their length; lower cauline leaves 8-13 cm long, 6-17 mm wide, linear to narrowly elliptic, early deciduous; mid to upper cauline leaves, 4-10 cm long, 14-42 mm wide, broadly lanceolate or ovate, sessile with cordate and subclasping bases. Pedicel 12-23 mm long in fruit. Calyx lobes (3.5-)4-5(-5.5) mm long, narrowly to broadly oblong. Corolla limb white, 12-19 mm wide; tube 4 mm long. Fornices with appendages very minutely papillate-puberulent, emarginate, the whole fornix much longer than broad. Anthers 0.7-1 mm long. Nutlets 5-6 mm long, ovate; dorsal surface verrucose-hispidulous, the intramarginal prickles minute, ca. 10; marginal prickles distinct to their bases or nearly so, mostly all 3-4 mm long but with a few shorter glochidia along the edges of the long prickles. Chromosome number, 2n = 24.
Discussion:Lappula bella Macbr., Contr. Gray Herb. 48: 39. 1916.
Lappula rattanii Brand, Feddes Repert. Sp. Nov. 18: 311. 1922.
Hackelia rattanii (Brand) Brand, Pflanzenr. IV. 252(Heft 97): 129. 1931. Type: CALIFORNIA. Mendocino County: in the Coast Range, north of San Francisco Bay, 1000-1300 m, June 1884, Volney Rattan 45.
Type. CALIFORNIA. Trinity County: Dorleska, in the Salmon Mountains, elevation 2,000 meters, July 21, 1909, H. M. Hall 8599 (holotype, GH!; isotypes, DS!, MO!, F!, UC!, US!, ORE!).
Hackelia bella is a very robust diploid (2n = 24) with large, distinct, showy white flowers, and large nutlets. Like its diploid relatives, it appears to be a much better competitor than any of the tetraploids. Although most frequently found in disturbed sites, it is commonly seen growing in stable, fairly complex communities.
The taxon is probably most closely related to Hackelia amethystina, which is found to the south of its range. It differs from the latter in having larger white flowers with a longer tube; having the appendages of the corolla longer, differently shaped, and only minutely papillate-puberulent; and in having larger calyx lobes, pedicels longer in fruit, and larger nutlets. These two taxa are without doubt related to H. micrantha.
Hackelia rattanii has been referred here by many recent workers including I. M. Johnston (1923). Without having seen the type, it is with some doubt that we place this taxon here. There are several parts of Brand’s description of Lappula rattanii that leave a question as to its relationship. The most disturbing statement is his description of the corolla appendages; “fornices minute papillosi, semilunares, latiores quam longi.” Although it is difficult to determine exactly what he means (due to the variable usage of terms) one could easily mistake this description as a characterization of Hackelia amethystina.
The taxonomy and evolution of Hackelia in northern California are very poorly understood. Further collecting in the region north of San Francisco will quite likely result in the delineation of several new taxa and from all indications may divulge extensive hybridization between them. Because of the large number of problematical and quite possibly undescribed forms from this area, we choose not to change the synonymy of H. bella at this time.
Examples of unusual material of this region are the collections of Howell & True numbered 43354, 43355, 43356, 43356A (CAS). These specimens appear to represent as many as three different taxa or possible hybrids and are all from the same locality of Hough Mountain in Plumas County. Collection number 43354 might well be H. bella, but further collecting would be necessary before such an extension of range could be accepted.
Distribution:United States of America North America