IB 168 – Plant Systematics Laboratory 10: “Basal “Angiosperms 2

In today’s lab we finish looking at the “basal” angiosperm families with two families of the so-called “paleo-herbs” in the Piperales and begin looking at a few basal families of the eudicots. The eudicots are a monophyletic group diagnosed by the shared feature of tricolpate pollen. There are more features that unite the eudicots that will be discussed in lecture and lab in the coming week. For vocabulary this week, note that “actinomorphic” = radially symmetric, and “zygomorphic” = bilaterally symmetric, and “-merous” = “in multiples of”.

PIPERALES (MAGNOLIID “PALEO-HERBS”)

Aristolochiaceae – 12 genera, ~475 spp., tropical and warm temperate Leaves alternate and simple, often heart shaped; stipules lacking; scrambling herbs or woody vines (rarely shrubs); bisexual flowers, actinomorphic to strongly zygomorphic; generally three sepals which are petaloid, connate and fused to the ovary at their base; petals usually absent; flowers generally solitary; stamens 6-12, connate at their base and partially adnate to the ovary; partially to fully inferior ovary of three to six fused carpels, each carpel having one locule; one style with 4-6 stigmas; flowers often smell of rotting meat.

Aristolochia Asarum

Piperaceae – 8 genera, ~3000 spp.; tropical Leaves usually spirally arranged, simple; stipules may be present or absent; often vines; may be herbs, shrubs, or trees; flowers very reduced, bisexual or unisexual, sunken in a fleshy spike, born in the axils of small peltate bracts; both sepals and petals absent; stamens one to ten in number, distinct; superior ovary composed of two to five connate carpels; ovary with one locule and a single ovule; stigmas two to five in number, sessile; inflorescence often appearing opposite to leaves due to development of axillary shoot.

Macropiper Peperomia Piper

All the families that follow are part of the Ranunculales

Ranunculaceae – 62 genera, ~2450 spp., mostly temperate and boreal Leaves usually alternate-spiral, simple or pinnately or palmately-compound or lobed; stipules generally absent; typically herbs, shrubs or vines; flowers bisexual and actinomorphic (rarely unisexual or zygomorphic) all parts free; sepals 5 (can be 3-15), sometimes petaloid; petals 5 (sometimes 4, many, or even absent); stamens generally numerous (>20), distinct, anthers opening via longitudinal slits; superior ovaries; five to many distinct carpels, each with a single locule and one to many ovules; one style per carpel; fruits usually dry achenes, also follicles & berries.

Aquilegia Clematis Delphinium Helleborus Ranunculus 1 IB 168 – Plant Systematics

Papaveraceae – 23 genera, ~225 spp., Leaves usually spirally arranged, simple or (pinnately) dissected; stipules lacking; herbs or shrubs, less often trees, usually with a milky or colored sap; flowers bisexual, actinomorphic (rarely zygomorphic); sepals two, (rarely 3 or 4), distinct, often deciduous; generally twice as many petals as sepals (4 or 6) (sometimes more or absent altogether); stamens numerous (occasionally 4 or 6), distinct; superior ovary of two to many fused carpels; ovary with one locule with numerous ovules; styles 1 or equaling number of carpels, stigma usually lobed; fruits usually capsules.

Argemone Dendromecon Eschscholzia Papaver Platystemon

Berberidaceae – 15 genera, ~675 spp., mostly Northern temperate Leaves usually alternate-spiral (opposite in Podophyllum), often lobed or pinnately-compound, commonly serrate-dentate or spiny; stipules generally lacking; herbs or shrubs; bisexual flowers, actinomorphic; sepals four to many in number, distinct; petals four to many in number, distinct, occasionally separated into inner and outer petal whorls; sepals and petals similar, in 2 or more series of 6 or 4 segments; stamens typically six, opposite petals, distinct, anthers opening by pores with lids; superior ovary of one carpel having a single locule with two to many ovules; one style or stigma sessile; wood and root tissue usually pale to bright yellow from berberine content.

Berberis Podophyllum Vancouveria

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