CHARACTER CLASSIFICATION

The general groups of characters I-XII are considered character classes which include several types of characters each of which is defined. The states of each character are arranged by order of importance and defined in Section B of this chapter. This arrangement of character states by character and ordering or ranking of types of character within a character class is an attempt to make this classification comparative and precise. See Chapter 5 for basic definitions of characters and kinds of characters as well as types of evidence.


I. POSITION AND ARRANGEMENT (A Character Class with character types 1-8 as listed below. States of each character type are in Section B I of this chapter).
  1. Location. Position of organs or parts in relation to their surrounding environment (See Section B I A for the character states of this character type).
  2. Position. Location or attachment of organs or parts with respect to other, dissimilar organs or major parts (See Section B I B).
  3. Arrangement. Disposition of organs or parts with respect to one another (See Section B I C).
  4. Orientation. Divergence of organs or parts with reference to a central axis or point (See Section B I D).
  5. Transverse Posture. The relation of the ends of a single organ or part to its center or transverse axis (See Section B I E).
  6. Longitudinal Posture. The relation of the margins of a single organ or part to its central longitudinal axis (See Section B I F).
  7. General Structural Position. The point, spot, local or general region of or on a single structure; e.g., the apical region of a leaf, the central point of a petal (See Section B I G).
  8. Embryonic Position. Position and arrangement of immature organs or parts.
    • Aestivation or Prefloration. Arrangement, in the strict sense of I 3, of embryonic floral parts. Note: aestivation for the calyx and corolla can be the same or different within a flower bud (See Section B I H).
    • Ptyxis. The rolling and folding of embryonic leaves in relation to a central point, transverse axis or longitudinal axis; a combination of transverse and longitudinal posture for embryonic parts (See Section B I H).
    • Vernation. The arrangement, in the strict sense of I 3, of embryonic leaves. Most authors treat ptyxis as this.

II. NUMBER AND SIZE
  1. Number. Any value or range of values expressing absolute count, sum or aggregate of individual units; or an expression of relative or comparative units (See Section B II A).
  2. Size. Spatial dimensions or proportions of any organ or its parts, usually expressed as number values in reference to length, width, and depth; or an expression of relative or comparative amounts (See Section B II B).
  3. Cycly. The absolute number of whorls of parts, such as number of whorls of floral parts or leaves (See Section B II C).
  4. Merosity. The absolute number of parts within a whorl, such as the number of petals in the corolla or number of stamens in an androecial whorl (See Section B II D).
  5. Fusion. The coalescence or union of like or unlike organs or parts (See Section B II E).
  6. Division. The separation, divergence, or forking into segments, parts, lobes, and branches of any organ or its parts (See Section B II F).

III. SHAPE AND OUTLINE
  1. Shape. An outline of specific form which is plane or two-dimensional; or a specific figure which is three dimensional (See Section B III A).
  2. Apex. The tip of a two-dimensional structure which is usually bounded by the upper 5-10% of the margins; or the top of a three-dimensional structure (See Section B III B).
  3. Margin. The border region of the side of a two-dimensional or plane structure (See Section B III C).
  4. Base. The lower portion of a two-dimensional structure which is usually bounded by the lower 5-10% of the margins; or the bottom of three-dimensional structure (See Section B III B).

IV. SURFACE, VENATION, TEXTURE
  1. Configuration. Surface pattern usually resulting from internal structural form, exclusive of venation (See Section B IV A).
  2. Venation. Vein arrangement visible on the surface (See Section B IV B). For internal venation features see Venation in Chapter 7.
  3. Surface. Features derived from epidermal outgrowths or excrescences, exclusive of trichome cover types (See Section B IV C).
  4. Vestiture or Indument. Trichome cover types (See Section B IV D). For individual trichome types see Trichomes in Chapter 7.
  5. Texture. Characteristic physical condition or consistency of an organ or its parts (See Section B IV E).

V. SEX
  1. Flower. Sexual condition of the individual flower (See Section B V A).
  2. Inflorescence. Arrangement of flowers by sexual condition within an inflorescence; or total diversity of flower sexual conditions within an inflorescence (See Section B V B).
  3. Plant. Total diversity of flower sexual conditions within a single plant (See Section B V C).
  4. Population or Species. Total diversity of flower sexual conditions within a population (See Section B V C).

VI. POLLINATION AND FERTILIZATION
  1. Pollination Type. Agent by which pollen is transferred from the pollen sac or anther to the stigma or ovule (See Section B VI A).
  2. Pollination Pathway. Structural route that the pollen tube traverses in reaching the ovule (See Section B VI B).
  3. Fertilization Type. Source(s) of male gametes for fertilization (See Section B VI C).
  4. Fertilization Pathway. Structural route that the pollen tube traverses to the embryo sac after reaching the ovule (See Section B VI D).

VII. TEMPORAL PHENOMENA
  1. Periodicity. Recurrence of growth phenomena at regular time intervals; or seasonality of occurrence of plant growth phenomena (See Section B VII A).
  2. Maturation. Relative development time of different plant organs or parts (See Section B VII B).
  3. Duration. Length of time that a plant or any of its component parts exists (See Section B VII C).

VIII. GROWTH AND DEVELOPMENT
  1. Growth Region. Location of meristematic region on or within an organ or its parts (See Section B VIII A).
  2. Growth Periodicity. Recurrence or duration of meristematic activity within an organ or its parts (See Section B VIII B).
  3. General Development. Direction of maturation within the plant of its organs or its parts; e.g., from the base upward or from the inside outward (See Section B VIII C).
  4. Developmental Shoot Types. Origin and maturation of different shoots (stem with leaves) (See Section B VIII D).

IX. PATTERNS
  1. Symmetry. Correspondence of parts in size, form and arrangement on opposite sides of a plane, line, or point (See Section B IX A).
  2. Arrangement Systems. Total disposition of organs with respect to each other based on the angle of divergence between succeeding similar parts (See Section B IX B).
  3. Branching Patterns. Position of branches on the main axis and the arrangement of the lateral branches (See Section B IX C).

X. SECRETORY AND EXCRETORY STRUCTURES
  1. Functional Types. The chemical nature of the substance secreted or excreted (See Section B X A).
  2. Positional Types. Location of glands on organs or parts (See Section B X B).

XI. COLORATION
  1. Standard. Color determinations based on accepted color charts and codes (See Section B XI A).
  2. Distribution. Patterns of color variegation on an organ or parts (See Section B XI B).

XII. GENERAL
  1. General. Descriptors applicable to any character.