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Key to California Plant FamiliesDavid J. Keil, as revised by Alan R. Smith and Thomas J. Rosatti to include CyatheaceaeOnly vascular plants are treated in The Jepson eFlora. Vascular plants are a monophyletic group or clade that includes (1) Lycophytes (often superficially moss-like but with thicker scale-like leaves and axillary sporangia that are often borne in cones), (2) Ferns (most with sporangia borne on abaxial leaf surfaces, a few with sporangia on modified leaf segments or in hard sporangium cases), and Equisetum, with whorled scale leaves and sporangia grouped in terminal cones, (3) Gymnosperms (with seeds generally produced in cones of various forms), and (4) flowering plants (with seeds developing in ovaries of flowers). Flowering plants in California include five clades: Nymphaeales, Magnoliids, Ceratophyllales, Eudicots, and Monocots (see back inside cover). Unlike all other organisms, vascular plants have true roots, stems, and leaves, with water- and nutrient-conducting (vascular) tissues that also provide structural support. In terrestrial (and aquatic) environments, true mosses and leafy liverworts may appear superficially similar to vascular plants, but their minute leaves are filmy (generally only 1 cell layer in thickness), and their delicate, usually short stems are attached to soil or other substrate by fragile filaments of 1 or more cells (rhizoids) that lack conducting tissue. Mosses, the most diverse land plants in California other than vascular plants, have alternate, closely overlapping, scale-like or narrowly linear leaves and produce solitary sporangia (generally finely stalked) at the tips of leafy shoots. Some freshwater liverworts can be confused with free-floating vascular plants that lack clearly differentiated stems and leaves, but the liverworts can be recognized by their forking body plan or forked grooves on their upper surface. Although in aquatic environments an emergent habit distinguishes vascular plants from other aquatics, potential for confusion of vascular plants with organisms other than mosses and liverworts in fully submersed settings warrants attention. In particular, some marine algae, such as kelps and rockweeds, appear superficially similar to vascular plants because of leaf-like, stem-like, and root-like (holdfast) structures. These algae, however, have accessory pigments ranging in color from olive-green to reddish or brownish that distinguish them from marine vascular plants, which are grass-green in color. Some of these algae have gas-filled floats, which are not found in marine vascular plants, and all of them are somewhat rubbery in texture, in contrast to the papery texture of marine vascular plants. Green alga e are similar in color to vascular plants; of these, charophytes, with a central axis and whorled, cylindric branches (but no leaves) are most readily confused with vascular plants. Keys in the Jepson eFlora, are based primarily on structures associated with sexual reproduction (e.g., sporangia, cones, flowers, fruits). The eFlora does not provide a means for keying terrestrial vascular plants that are in strictly vegetative condition. For aquatic vascular plants, some of which reproduce mostly by vegetative means, a key is provided that allows identification using only vegetative characteristics. A key is also provided for identification of the few species in which tiny bulblets (small bulbs or corms) take the places of flowers in modified inflorescences or inflorescence-like clusters. — Scientific Editor: Bruce G. BaldwinKey To Groups
1. Specimens available for examination without flowers, these either not present on the specimen or not produced at all
2. Bulblets [small bulbs Short underground stem and the fleshy leaves or leaf bases attached to and surrounding it (e.g., an onion). or corms that are dispersed in place of seeds or fruits] formed in place of flowers in inflorescence or inflorescence-like cluster ..... Group 1
3. Sporangia, sporangium In non-seed plants, a case or sac in which spores are produced, and from which they are released. cases, seeds, cones, or cone-like structures 0 or not readily apparent [plants in strictly vegetative condition]
4' Plant terrestrial [Note: terrestrial plants in strictly vegetative condition cannot be identified with this key]
3' Sporangia, sporangium In non-seed plants, a case or sac in which spores are produced, and from which they are released. cases, seeds, cones, or cone-like structures present
5. Herbs reproducing by spores released directly from sporangia, the sporangia variously located [on abaxial leaf Organ arising from a stem, generally composed of a stalk (petiole) and a flat, expanded, green, photosynthetic area (blade); distinguished from a leaflet by the presence in its axil of a bud, branch, thorn, or flower; sometimes with lateral, basal appendages (stipules); either simple (toothed, lobed, or dissected but not divided into leaflets) or compound (divided into leaflets). face, in stalked cluster arising from petiole Leaf stalk, connecting leaf blade to stem; sometimes more or less indistinct. or blade Expanded portion of a leaf, petal, or other structure, generally flat but sometimes rolled, cylindric, wavy, or cupped. base, in hardened case at petiole base, in axils of linear Elongate, with nearly parallel sides; narrower than elliptic or oblong. or scale-like leaves, or in terminal cone-like structure], seeds and pollen never formed [LYCOPHYTES and FERNS] ..... Group 3
5' Herbs to trees reproducing by seeds
6. Ovules exposed to air at time of pollination, not enclosed in ovary; pollen grains deposited directly on ovule, stigma 0; seeds, if present, borne between scales of cone or naked on branches, fruit not produced; shrubs or trees [GYMNOSPERMS] ..... Group 4
6' Ovules enclosed in ovaries that on available specimens have matured as dehiscent Opening at maturity to release contents; usually pertaining to anthers or fruits. or indehiscent Not opening inherently to release contents; usually pertaining to fruits. fruits; seeds enclosed within ripened pericarp of fruit [if dry remains of flowers are present it may be possible to determine the family of a fruiting specimen under 1' in this key, but not all fruiting specimens may be identifiable here]
1' Specimens available for examination with flowers, often also producing seeds within fruits [ANGIOSPERMS]
7. Specimens with only cleistogamous flowers — fruits developing without flowers opening ..... Group 5
7' Specimens with open flowers
8. Specimens with unisexual flowers of only 1 kind [staminate or pistillate, but not both]; plants dioecious or monoecious
9. Specimen with only staminate flowers
10. Herb or subshrub, woody only at base ..... Group 6
10' Tree or shrub, conspicuously woody ..... Group 7
9' Specimen with only pistillate flowers
11. Herb or subshrub, woody only at base ..... Group 8
11' Tree or shrub, conspicuously woody ..... Group 9
8' Specimens with bisexual Both male and female reproductive parts occurring and functional in the same plant or structure (e.g., flower, spikelet, inflorescence). flowers or with both staminate and pistillate flowers [on same or different individuals]; plants bisexual, dioecious, or monoecious (occasionally with mixture of bisexual and unisexual flowers)
12. Pistils 2 or more per flower [carpels > 1, free to the base] ..... Group 10
12' Pistil 1 per flower [carpel 1 or carpels > 1 fused at least proximally]
13. Perianth 0 or in a single whorl [appearing to be either sepals or petals but not both], sometimes reduced to scale-like or bristle-like structures
14. Tree or shrub, conspicuously woody
15. Inflorescence, at least the staminate, a catkin Spike or spike-like (e.g., Alnus) inflorescence of unisexual flowers with inconspicuous perianths (generally wind-pollinated), usually pendent and often with conspicuous bracts. or catkin-like spike 1. In flowering plants excluding Asteraceae, Cyperaceae, Poaceae, and some other groups, an unbranched inflorescence in which the flowers are sessile and nearly always open from the bottom to the top of the inflorescence. 2. In Asteraceae, Cyperaceae, Poaceae, and some other groups, a spike-like inflorescence is one in which the inflorescence units (e.g., heads in Asteraceae; spikelets in Cyperaceae and Poaceae), instead of individual flowers, are sessile and attached directly to the main axis of the inflorescence, not to branches, and in which floral development may or may not proceed as in 1. ; flowers unisexual ..... Group 11
15' Inflorescence various but not catkin-like; flowers bisexual Both male and female reproductive parts occurring and functional in the same plant or structure (e.g., flower, spikelet, inflorescence). or unisexual ..... Group 12
14' Herb or subshrub, woody proximally if at all
16. Leaf venation parallel or leaves and stem not differentiated ..... Group 13
16' Leaf venation generally pinnate Feather-like; pertaining to veins, lobes, leaflets, or other structures arranged in two dimensions (i.e., in one plane) along either side of an axis; a leaf is odd-pinnate if there is a terminal leaflet, even-pinnate if there is not, and either odd- or even-pinnate may be 1-pinnate (blade divided into primary leaflets), 2-pinnate (primary leaflets divided into secondary leaflets), 3-pinnate (secondary leaflets divided into tertiary leaflets), etc. or palmate More than two structures or parts (e.g., veins, lobes, or leaflets) radiating from a common point in two dimensions (i.e., in one plane). (sometimes only midvein evident) or leaves reduced to bladeless scales
13' Perianth in 2 or more whorls (generally both sepals and petals) or perianth parts spiraled 2 or more times around floral axis
18' Perianth parts generally 4 or 5 per whorl (rarely some other number or whorls differing in number of parts) or in a spiral with the number of parts indefinite
19. Petals fused into a ring or a tube, the corolla generally falling as a unit [corolla of free petals fused to a hypanthium Structure generally in the shape of a tube, cup, or bowl, derived from the fused lower portions of the perianth and stamens, from which these parts seem to arise, and to which the ovary wall is fused in an inferior ovary (to which the ovary wall is partially fused in a half-inferior ovary; from which the ovary is free in a superior ovary). should be keyed under 19']
21. Corolla bilateral Divisible into mirror-image halves in only one way. ..... Group 18
21' Corolla radial Divisible into mirror-image halves in three or more ways. ..... Group 19
19' Petals free, at least at base, attached and generally falling singly (sometimes individually joined to a hypanthium Structure generally in the shape of a tube, cup, or bowl, derived from the fused lower portions of the perianth and stamens, from which these parts seem to arise, and to which the ovary wall is fused in an inferior ovary (to which the ovary wall is partially fused in a half-inferior ovary; from which the ovary is free in a superior ovary). ; in a few families ± joined and falling in groups, but not forming a ring or a tube, or petal 1)
22. Leaf compound or so deeply divided as to appear compound ..... Group 20
22' Leaf simple Composed of a single part; undivided; unbranched. , sometimes much reduced
24' Stamens <= 2 × as many as petals
25' Herb or subshrub, woody only at base ..... Group 24
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