Corylus cornuta Marshall subsp. cornuta

Holstein, Norbert, Tamer, Sarah el & Weigend, Maximilian, 2018, The nutty world of hazel names - a critical taxonomic checklist of the genus Corylus (Betulaceae), European Journal of Taxonomy 409, pp. 1-45 : 21

7a. Corylus cornuta Marshall subsp. cornuta

Note: it has been recognized as having two subspecies by Flora of North America ( Furlow 1997) and World Checklist and Bibliography of Fagales ( Govaerts & Frodin 1998) .

C. rostrata Aiton, Hortus Kewensis 3: 364 ( Aiton 1789). – Original citation: “Cult. [since] 1745 by Archibald Duke of Argyle” [sic!, Archibald Campbell, third Duke of Argyll, who laid the groundstock for Kew Botanical Gardens] and “Nat. of North America.” Material from the cited Gronovius (1762): “Crescit in Dragon swamps” [a river in Virginia, USA]. – Type: Cult., Hort. Bni [Botanici] Collinson, Mill Hill, s. coll., s.n. (neo-, designated here: BM001191197!). – Note: the first author did not find any original material in the relevant herbaria. In order to explore which material might be taken into account, we briefly discuss the origin of the name here. As there is no explicit indication of an author, the name is to be attributed to Aiton (Art 46.8. ICN, McNeill et al. 2012). However, the original author of C. rostrata is apparently Daniel Carlsson Solander. Although the third volume was mainly edited by Dryander ( Stafleu & Cowan 1976 –1988), Dryander largely used Solander’s manuscripts ( Britten 1912), and in the Linnean herbarium, there is a specimen of what is now understood as C. cornuta (LINN 1132.2) where J.E. Smith writes “ C. rostrata Mss. 83. 931” and “ C. rostrata Soland [er] Ait. H. Kew v.3 364.” As a contemporary of the publication, Smith likely knew who the author of the name was, while 81 and 931 might be interpreted as manuscript fragments. Therefore, possible original material needs to be linked to Solander’s collections. Two sources are cited in the protologue, material from Duke Argyll’s garden and Gronovius’ Flora Virginica ed. 2 ( Gronovius 1762). Material from Gronovius is usually found in the Clayton Herbarium ( Stafleu & Cowan 1976 –1988), but there appears to be no original material of this taxon. Also, the number cited for Clayton’s herbarium in Gronovius’ Flora Virginica ed. 2 is erroneous, because Clayton 747 is a Juglans sp., which is already cited on the previous page. There is a specimen in BM (BM001191197) by Peter Collinson (1694–1768) from Mill Hill, where Collinson lived from 1749 on ( Living & Braithwaite 2013). Collinson obtained material from Gronovius for cultivation ( Reveal & Pringle 1993), and Collinson was also in contact with Solander. Thus, the specimen might be derived from Gronovius’ collection. In addition, as a student of Linnaeus, Solander had access to his herbarium, so the LINN specimen (LINN 1132.2) might also be taken into consideration. However, neither Collinson’s specimen nor the one from the Linnean herbarium can unambiguously linked to Solander, so they are not original material, making a neotypification necessary. Due to be possible link and the completeness of the specimen, we choose the specimen from Collinson’s garden as neotype.

C. cornuta f. inermis Fernald , Rhodora 38: 76 ( Fernald 1936). – Original citation: “ Quebec: abundant in border of woods, East Broughton”. – Type: Canada, Quebec, East Broughton, 28 Aug. 1915, M.L. Fernald and H.B. Jackson 12073 (holo-: GH).

C. cornuta var. megaphylla Vict. & Rousseau, Contributions de l’Institut Botanique de l’Universite de Montréal 36: 13 ( Marie-Victorin & Rousseau 1940). – Type: Canada, Quebec, Matapédia, sur les îles de la Restigouche, à l’embouchure de la Matapédia (frontière du Nouveau-Brunswick), 15 Aug. 1928, J.L.C. Marie-Victorin and Rolland-Germain 28690 (lecto-, designated here: MT00132174!; isolecto-: MT00132175!). – Additional type material: Canada, Quebec, thickets and borders of woods, near mouth of Marsouin River (Gaspé Co.), 26 Jul. 1922, M.L. Fernald and A.S. Pease 25014 (syn-: MT00206842!). – Note: Marie-Victorin & Rousseau cited the two collections and mentioned that the type is in the herbarium of the Université de Montreal (MT). However, there are two specimens of Marie-Victorin and Rolland-Germain 28690 in MT, of which one is annotated as a type, and one specimen of Fernald and Pease 25014 (Geoffrey Hall, MT, pers. com.). The annotated specimen is here formally designated as lectotype.