Rubus elegantulus Blanchard

Rubus amicalis Blanchard, Rhodora 13: 56. 1911
Rubus amabilis Blanchard, Rhodora 8: 173. 1906. Not R. amabilis Focke. 1905.
Stem erect, 1-2 m. high, glabrous, glandless, 5-angled and furrowed, almost unarmed; prickles small, straight, slender; leaves of the turions 5-foliolate; leaflets rather thick, darkgreen, shining, when young sparingly appressed-hairy above, lighter-green and glabrous beneath, oblanceolate or lanceolate, long-acuminate, finely doubly serrate, acute or obtuse at the base; middle leaflet 7-13 cm. long, its petiolule 2-3 cm. long; outermost leaflets 5-10 cm. long, subsessile; stipules subulate, about 1 cm. long; petioles 5-8 cm. long, glabrous, glandless, unarmed or armed with minute recurved prickles; leaves of the floral branches much smaller, ternate; leaflets less acuminate; inflorescence racemose, 7-10 cm. long, sparingly villous but glandless; bracts broadly lanceolate; sepals ovate, acuminate, 5 mm. long, glabrous without, tomentose within; petals white, 12-18 mm. long, oval; fruit black, oblong, 12-18 mm. long, 9-12 mm. thick; drupelets 15-40, coherent, pulpy; putamen strongly reticulate, keeled, 2.5 mm. long.
Type locality: Grove Depot, Kennebunk, Maine. Distribution: Maine to Nova Scotia.

Rubus elegantulus Blanchard, Rhodora8: 95. 1906
Stems biennial, erect, 1-1.5 m. high, glabrous, red, angled and furrowed, rather slender, armed on the angles with slender, slightly retrorse prickles; leaves of the turions 5-foliolate; stipules subulate, 1-1.5 cm. long; petioles, petiolules, and midveins armed with slender, retrorse prickles, glabrous; leaflets dark-green above, slightly lighter beneath, glabrous or nearly so on both sides, oval or ovate, long-acuminate at the apex, 5-10 cm. long, finely and sharply double-serrate, with ovate-lanceolate teeth; terminal leaflet usually rounded at the base and with a petiolule about 2 cm. long, the others usually acute at the base, the lateral ones with petiolules about half as long and the outermost subsessile; branches of the floral stems 1-3 dm. long, sparingly pubescent and somewhat prickly; leaves 3-foliolate or some of the. upper 1-foliolate; leaflets 2-7 cm. long, more oval or obovate, and more coarsely toothed than those of the turions, the median one with a petiolule 1 cm. long or less, the lateral ones sessile, all acute at the base; inflorescence corymbose or short-racemose; peduncles and pedicels sparingly villous, often with a few prickles; sepals ovate, acuminate, 5-6 mm. long, puberulent without, tomentose within; petals white, oval, 10-12 mm. long; fruit hemispheric, or somewhat elongate, 8-10 mm. long, black, sweet; drupelets rather large, glabrous.
Type locality : Signal Hill and its northern borders in Alstead, New Hampshire. Distribution: Maine to Vermont.

Rubus elegantulus, the showy blackberry, is an uncommon North American species of flowering plant in the rose family. It grows in the northeastern and north-central United States (from Maine to West Virginia, plus Wisconsin and Minnesota) and eastern Canada (Québec, Newfoundland, and all 3 Maritime Provinces).

Rubus elegantulus is an erect perennial 2–4 feet (30–120 cm) tall, with prickles but no hairs. Leaves are palmately compound with 5 leaflets, slightly darker on the upper surface than on the lower. Fruits are black, nearly spherical.

The genetics of Rubus is extremely complex, so that it is difficult to decide on which groups should be recognized as species. There are many rare species with limited ranges such as this. Further study is suggested to clarify the taxonomy. Some studies have suggested that R. elegantulus may have originated as a hybrid between R. allegheniensis and R. pensilvanicus.