Bi 321 (2010) Floras, Manuals, & Botanical Descriptions Dr. Dutton

(Including Identification & Keys)

How To Put a Name on it?

•

• Compare unknown with labeled specimens

• Compare unknown with labeled illustrations

• Keys

– ____________________ = with analysis on a character by character basis (Most)

– ____________________ = with a brief statement or general view about the characters of a species

Construction of Keys

• Indented (or yoked)

• Bracketed (or parallel)

– See Overheads & Lab Packet

• Indented – Advantages

–

– Places similar plants closer together

• Bracketed – Advantages

–

– Saves paper

Indented key to 5 genera of Ranunculaceae:

1. Fruit a group of achenes; flower not spurred

2. Petals none

3. Sepals usually 4; involucre none. . . . .. . . . . …. Clematis

3. Sepals usually 5; involucre present . . . . . . . . . Anemone

2. Petals present . .. . . . . . . . . . . . . . . . . . . . . . . . . Ranunculus

1. Fruit a group of follicles; flowers spurred

4. Flowers regular; spurs 5 . . . . . . . . . . . . . . . . . . . .. Aquilegia

4. Flowers irregular; spur 1 . . . . . . . . . . . . . .. . . . . .Delphinium

Bracketed key to 5 genera of Ranunculaceae

1. Fruit a group of achenes; flowers not spurred . . . .. . . . .. . . . 2

1. Fruit a group of follicles; flowers spurred . . . . . . . .. . . . . ….. . 4

2. Petals none . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2. Petals present . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Ranunculus

3. Sepals usually 4; involucre none . . . . . . . . . . . . . . . . . Clematis

3. Sepals usually 5; involucre present . . . . . . . . . . . . . . Anemone

4. Flowers regular; spurs 5 . . . . . . . . . . . . . . . . . . . . . . . Aquilegia

4. Flowers irregular; spur 1 . . . . . . . . . . . . . . . . . . . . . .Delphinium

The “Structure” of “Good” Keys

• ____________________ - “leads” arranged in couplets

• Each lead takes user to a couplet or a name

• Each lead may refer to one or more characters

• Sequence of characters in the leads of a couplet are contrasting

• Each lead begins with the same noun followed by an adjective(s)

• Consecutive leads commonly emphasize different structures

• Most “reliable” characters listed ____________________ in a lead

• Both leads in a couplet are usually numbered or lettered

• Avoid unnecessary ____________________

• Avoid all-inclusive ____________________

• Use ____________________ measurements (not “large” or “small”) with constant units

• Try to use characters that are usually present (these tend to be vegetative)

• Use comparison charts whenever possible

Let’s Make a Key!

• See the overheads and handouts

Computers & Plant Identification

• Computer technology is providing character data handling opportunities not previously possible

– Detailed and possibly large data bases of taxa and their characters

– Sort and search capabilities for …

• Making comparisons

• Constructing keys

– Interactive keys

• Not constrained to following a printed topology (i.e., following a series of steps thorough dichotomous choices)

• Users can access features that are readily available for key

• We will see a detailed example later and soon

Floras & Manuals

• Floras & Manuals are sometimes treated/used interchangeably (the term Handbook is also sometimes used)

– They are taxonomic treatments of all plants occurring within a specific geopolitical area

– They utilize results obtained in monographs & revisions

• Floras can be:

– World wide

– Continental

– National

– Regional

– Local

– see your Handbook

• They typically include:

– keys to identification

– descriptions of plants

– ecology, geology, soils information

– distributions, including maps

– phenology (timing of life history events)

– associated species

– habitat

– notes on abundance/conservation concern

– ethnobotanical information

Botanical Descriptions

• Are important!

• They allow you to confirm the identity of a plant (or plants) you are trying to identify

• Compare the information in a key to species with a botanical species description of one of the species in a key

• Look at:

– Ranges of measurements

– Adjectives used in both keys and descriptions

– Note the use of parentheses

Sample Treatments

• Most manuals include:

– A key to families

– A taxonomic description of each family

– A key to genera within each family (for families > 1 genus)

– A taxonomic description of each genus

– A key to species within each genus (for genera > 1 species)

– A taxonomic description of each species

– Keys and description for infraspecific taxa may be included as well