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Kitty Kohout  

Key to Wisconsin Aspleniaceae

Author: Robert F. Freckmann

    • 1a.Blades simple (rarely with a basal lobe separated as a pinna), long-tapering to a slender tip; margins entire to deeply lobed 2

    • 1b.Blades compound with several separate pinnae, or rarely with many deep lobes slightly connected by soft tissue; apex of blades not forming a long slender tip 3

    • 2a.Margins entire or shallowly undulate; blade tips often rooting, producing new plantlets; veinlets rejoining to form a network A. rhizophyllum

    • 2b.Margins deeply lobed; tip not rooting and forming plantlets; veinlets free at tips A. pinnatifidum

    • 3a.Blades 2 --3 times compound, with 2--5 widely-spaced pairs of irregular pinnae, deeply-lobed or divided into spatulate pinnules toothed at apex A. ruta-muria

    • 3b.Blades once compound with many closely-spaced pairs of regular oblong pinnae, not divided into pinnules 4

    • 4a.Fertile leaves erect, usually more than 20 cm tall, much longer than the spreading sterile leaves; pinnae with broad overlapping basal lobes projecting upward along the rachis; largest pinnae more than 8 mm long A. platyneuron

    • 4b.Fertile and sterile leaves similar, usually less than 20 cm tall; pinnae narrowed at base, not lobed or overlapping, less than 8 mm long 5

    • 5b.Upper part of petiole and rachis green to light tan A. viride

This is a worldwide family of two genera and about 730 species, especially notable for 23 recognized diploid hybrids involving almost every pair of North American species. Polyploidy is widespread, producing several fertile allopolyploid hybrid derivatives.