gymnosperms: nonflowering seed plants

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gymnosperms non-flowering seed plants
Alpha Families Beta Families Cycadales
(Order) Welwitschiaceae Ginkgoaceae Podocarpaceae
Pinaceae Araucariaceae Cupressaceae
(including Taxodiaceae) Taxaceae Ephedraceae Gnet
aceae
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Cycadales -- (Cycadaceae, Zamiaceae,
Stangeriaceae) the cycad families (11/185
tropical and subtropical)
gymnosperms
Plants seed plants, dioecious Habit shrubs or
trees with leaves arranged in terminal
rosettes Leaves tightly alternate forming a dense
terminal rosette pinnately compound some with
circinate vernation Pollen borne on strobili
with many spirally arranged scales 6-many pollen
sacs per scale (microsporophylls), on underside
(abaxial) Ovules borne on strobili with many
spirally arranged peltate scales or
megasporophylls Cycadaceae 2-8 ovules on
margin of megasporophyll Zamiaceae 2 ovules
underneath peltate-shaped megasporophyll Seeds
large, fleshy coat
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Ginkgoaceae -- the maidenhair tree family (1/1
found in Se Asia)
gymnosperms
Plants seed plants, dioecious Habit trees Leaves
alternate simple, fan-shaped with dichotomous
venation borne on long and short shoots
petiolate Pollen borne on spike-like clusters of
sporangiophores arising from axil of bud scale
or leaf on short shoot 2 reflexed pollen
sacs/sporangiophore Ovules borne on forking
peduncle arising from axil of leaf on short
shoot 2 (3) erect ovules each with subtending
collar Seeds large, fleshy coat
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Pinaceae -- the pine family (9-12/210
cosmopolitan)
gymnosperms
Plants seed plants, monoecious Habit shrubs or
trees Leaves alternate or closely fascicled on
determinate or indeterminate short shoots simple
and linear to needle-like Pollen borne on
strobili with many spirally arranged scales 2
pollen sacs per scale, on underside of scale
(abaxial) Ovules borne on cones (scale/bract
complex) woody at maturity with many spirally
arranged scales, flattened and free from
subtending bracts 2 ovules per cone scale, on
top of scale (adaxial) Seeds usually winged
(rarely wingless)
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Cupressaceae -- the cypress family (includes
Taxodiaceae) (28/156 cosmopolitan)
gymnosperms
Plants seed plants, monoecious or dioecious Habit
shrubs or trees Leaves alternate, opposite, or
whorled simple and scale-like, awl-shaped or
linear Pollen borne on strobili with many scales
2-9 pollen sacs per scale, on underside of scale
(abaxial) Ovules borne on cones (scale/bract
complex) usually woody at maturity (fleshy in
Juniperus) with several to many scales,
flattened or often peltate wholly adnate to
subtending bract 2-many ovules per cone scale,
on top of scale (adaxial) Seeds small, wingless
or narrowly winged
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Taxaceae -- the yew family (5/17-20 widely
distributed, mostly northern hemisphere)
gymnosperms
Plants seed plants, dioecious (rarely
monoecious) Habit shrubs or trees Leaves
alternate simple and linear or needle-like,
decurrent on twigs Pollen borne on strobili (look
like cones) with several flattened sterile basal
scales and 4-32 spirally arranged or whorled,
peltate or flattened structures called
sporangiophores that each bear 2-9 pollen
sacs Ovules solitary or in pairs, borne on
reduced cones (one scale) terminal on short
shoots Seeds solitary, surrounded by a tubular
green or red fleshy aril
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Taxaceae -- comments
gymnosperms
Comments interesting coniferous family you
commonly see Taxus cultivated around Cornell
campus. Which is more commonly planted, female
plants or male plants? Taxus brevifolia (from the
Pacific Northwest) is the source of Taxol, a
treatment for breast cancer. The aril is bright
red in Taxus and green in Torreya, which is named
after the famous American botanist John Torrey
(1796-1873).
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Ephedraceae -- the mormon-tea family (1/40
desert and semidesert regions of Northern
Hemisphere and South America)
gymnosperms
Plants seed plants, dioecious Habit shrubs, woody
vines (rarely trees) with jointed green,
photosynthetic stems Leaves opposite or whorled,
simple, scale-like, often deciduous Pollen borne
on spike-like strobili with 1-8 polleniferous
structures on a filament (each with 1-several
pollen sacs) each subtended by a pair of
bracts Ovules borne on strobili with 1-3 ovulate
structures each subtended by 2-4 pairs or whorls
of scale-like bracts Seeds dry or seeds and
subtending structures fleshy
Comments long-used in Chinese medicine, also as
a tea by western settlers. Synthetic analog
(pseudoephedrine) of active compound in many cold
remedies.
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Gnetaceae -- the gnetum family (1/30 Pantropical)
gymnosperms
Plants seed plants, dioecious (monoecious) Habit
shrubs, woody vines or trees Leaves opposite,
simple, entire, pinnately veined,
petiolate Pollen borne on aggregations of
polleniferous structures with 1 or 2 pollen sacs
(on filaments?) each structure surrounded by
a tubular bract Ovules borne whorled on
spike-like clusters with a solitary ovule
surrounded by a tubular bract Seeds large, with
tubular bracts forming a fleshy outer layer
Comments leaves, seeds, and tubers of several
species eaten in Southeast Asia and Africa
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Welwitschiaceae -- the welwitschia family (1/1
coastal desert of southwest Africa)
b family gymnosperms
Plants seed plants, dioecious Habit woody/fleshy
obconical stem with long tap root Leaves 2
opposite, strap-shaped, persisting throughout the
life of the plant and growing from the base
Pollen stalked polleniferous structures with 3
pollen sacs born in strobili with a
non- functional ovule in the center strobili
borne on branched axes Ovules also in strobili on
branched axes, ovule borne in bract axile
enclosed by two pairs of bracts, the inner pair
fused around the ovule Seeds with conspicuous
wings formed by inner pair of bracts
Comments a truly bizarre plant, very slow
growing and long-lived (more than 1000 years)
vessels present
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Araucariaceae -- the araucaria family (3/40
Asian tropics and south temperate South American
and Australian region)
b family gymnosperms
Plants seed plants, dioecious (rarely
monoecious) Habit trees Leaves alternate or
opposite, simple and needle-like, awl-shaped or
ovate Pollen borne on strobili with many scales
many pollen sacs per scale, on underside of
scale (abaxial) Ovules borne on cones
(scale/bract complex) woody with many spirally
arranged, flattened scales, wholly or partially
adnate to subtending bract ovules usually 1
(rarely 2) per cone scale, on top of scale
(adaxial) or embedded in scale cones
disarticulating at maturity Seeds winged and
breaking free from cone or wingless and
disspersed as a unit with scale/bract complex
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Podocarpaceae -- the podocarp family (13-17/172
south temperate and tropical)
b family gymnosperms
Plants seed plants, dioecious or monoecious Habit
trees or shrubs, rarely root parasites, branches
sometimes flattened and leaf-like
(cladodes) Leaves alternate ( rarely opposite),
simple and needle-like, scale like or with
flattened blades Pollen borne on strobili with
many spirally-arranged scales 2 pollen sacs per
scale, on underside of scale (abaxial) Ovules
borne on spikelike or reduced cones with 1-2
terminal ovules, each adnate to a cone scale and
bract and to a swollen fleshy cone axis Seeds dry
or fleshy sometimes with fleshy aril