''Rubus biformispinus'', the pasture dewberry, is an uncommon North American species of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the

rose family Rosaceae (), the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera. The name is derived from the type genus ''Rosa''. Among the most species-rich genera are '' Alchemilla'' (270), ''Sorbus ...

. It is found in eastern and central Canada (from

Ontario Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central C ...

Nova Scotia Nova Scotia ( ; ; ) is one of the thirteen provinces and territories of Canada. It is one of the three Maritime provinces and one of the four Atlantic provinces. Nova Scotia is Latin for "New Scotland". Most of the population are native Eng ...

) and the northeastern United States (

Maine Maine () is a state in the New England and Northeastern regions of the United States. It borders New Hampshire to the west, the Gulf of Maine to the southeast, and the Canadian provinces of New Brunswick and Quebec to the northeast and ...

, New York (state), New York, Pennsylvania).Blanchard, William Henry. 1906. Rhodora 8(93): 178–179
/ref> The epithet ''biformispinus'' means "with spines of two shapes," referring to the two distinct sizes of prickles on the stems. 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. biformispinus'' may have originated as a hybrid between ''Rubus setosus, R. setosus'' and ''Rubus flagellaris, R. flagellaris. ''Flora of North America, ''Rubus setosus'' Bigelow, 1824. Bristly blackberry, ronce sétuleuse
/ref>

References

Rubus, biformispinus Plants described in 1906 Flora of Canada Flora of the Northeastern United States {{Rubus-stub