1. Nyssa Linnaeus, Sp. Pl. 2: 1058. 1753; Gen. Pl. ed. 5, 478. 1754.
Tupelo [Classical Greek name for a water nymph, alluding to habitat] Tupelo [Classical Greek name for a water nymph, alluding to habitat]
Gordon C. Tucker
Tracy J. Park
Shrubs or trees; bark gray brown, rough, ridged; twigs with transverse diaphragms; winter buds scaly. Leaves: petiole terete or winged; blade usually elliptic to oblanceolate or obovate, rarely ovate, base cuneate to rounded. Pedicels: staminate present or absent, bisexual and pistillate absent [present]. Flowers: sepals forming a low rim; petals greenish to greenish white; style subulate or conic. Drupes usually blue-black (sometimes reddish purple in N. aquatica; yellow, orange, or red in N. ogeche), topped by persistent remnants of sepals; mesocarp juicy, acidic.
Species ca. 13 (5 in the flora): c, e North America, Mexico, Central America (Costa Rica, Panama), e Asia.
Plant sexuality in Nyssa is complicated and often difficult to determine. R. E. Burckhalter (1992) described all North American species as dioecious, without elaboration. The most widely distributed species in the flora area, N. sylvatica, has both staminate and morphologically bisexual flowers and appears to be androdioecious, but is functionally dioecious, as anthers of bisexual flowers do not dehisce (R. H. Eyde 1963; M. L. Cipollini and E. W. Stiles 1991). Similarly, the Chinese N. yunnanensis W. Q. Yin ex H. N. Qin & Phengklai appears to be androdioecious but is functionally dioecious; in this case pollen from the morphologically bisexual flowers is inaperturate and inviable, rendering the trees that bear these flowers functionally pistillate (Sun B.-L. et al. 2009). Nyssa ogeche appears to be polygamodioecious and other North American species appear to be monoecious or polygamomonoecious, but their reproductive biology has not been examined carefully.
Measurements of leaves refer to fully expanded ones from mid shoot (earlier leaves typically are smaller).
SELECTED REFERENCES Burckhalter, R. E. 1992. The genus Nyssa (Cornaceae) in North America: A revision. Sida 15: 323–342. Wen, J. and T. F. Stuessy. 1993. The phylogeny and biogeography of Nyssa (Cornaceae). Syst. Bot. 18: 68–79.
