A systematic treatment of fruit types

A SYSTEMATIC TREATMENT OF FRUIT TYPES
©The World Botanical Associates Web Page
Prepared by Richard W. Spjut
April 2003, March 2004
Abstract
The concept "fruit" and the terminology descriptive of fruit morphology are defined to distinguish the different kinds (types).  Some of the advantages and disadvantages to previous classifications of fruit types are discussed; the criteria considered tobe the most useful are adopted for a new systematic treatment.  This new treatment includes: (1) a key to 95 fruit types, (2) a systematic review of their names and definitions, and (3) an index to carpological terms. In the key up to six examples for each kind of fruit are indicated by reference to family (genus) name.  In the systematic review each fruit is defined; this is followed by (1)references to the original author and others who have applied the accepted term and/or its synonyms; (2) a discussion of its relationships to other kinds of fruits, and (3) citations of specimens, illustrations, and/or descriptions of taxa studied.  Thirty-seven new names or nomenclatural modifications to previous names for fruit types are made.  The materials studied are referenced by species namesunder family names according to the classification of Cronquist (1981) for angiosperms (Magnoliophyta), and accepted family names by Airy Shaw (1973) for gymnosperms.  Names for all fruit types are also listed in the index with reference to the original author, the date and place of publication, and the definition as originally presented by the author for each term; additionally, the index includesother carpological terms and their definitions.
What is a fruit: A fruit is a propagative unit developing from one or more fertilized egg cells (or rarely by parthenocarpy) enclosed by integuments and attached to megasporophylls, or a megasporophyll-scale complex, in a strobilus, cone, gynoecium, concrescent gynoecia, or gynoecia that disseminate together at the time it or its seed(s) aredispersed from the plant, or just prior to germination on the plant, and it may also include any other attached scales, bracts, modified branches, perianth, or inflorescence parts.




CLASSIFICATION OF FRUIT TYPES
A. Spermatocarpia (“naked seeds”)
     Spermidium. Seed lacking bracts or scales, integuments drupaceous, the outer fleshy, inner hardened (Gingoaceae).
     Arillocarpium. Seed witharil-like covering (Cephalotaxaceae, Taxaceae).
     Epispermatium.  Seed on a swollen or receptacle stalk (Podocarpaceae)
     Arcesthida. Seeds covered by fleshy bracts or scales (Gnetaceae, Cupressaceae [Juniperus]).
     Galbulus.  Scale and seed bract fused. (Araucariaceae, Cupressaceae, Taxodiaceae).
     Strobilus.  Seeds on frondlike sporophylls loosely aggregate at ends of shoots(Cycadaceae).
     Simple Cone. Seeds on scale-like sporophylls in a cylindrical arrangement (cone).
           (Ephedraceae, Stangeriaceae, Zamiaceae).
     Compound Cone.  Seed scales subtended by a distinct bract (Pinaceae, Welwitschiaceae).
 
B. Eucarpia (“covered seeds”)
     I. Simple Fruits. Seeds not dispersed from pericarpium, developing from one flower.
          Angiocarpi. Accessory (floral) parts enlarging with maturation of pericarpium (Anthocarp).
Dehiscent
               Tryma. Anthocarp dehiscent (Arecaceae [Atrocaryum munbaca], Juglandaceae [Carya], Thymelaeaceae [Thymelaea velutina]).
Indehiscent
Aril-like
               Glans.  Pericarpium subtended (basally) by accrescent floral parts (receptacle, peduncle, pedicel, bracts, or sepals) (17+ families:Anacardiaceae [Anacardium], Arecaceae [Calamus], Fagaceae [Quercus], Lauraceae [Aniba, Licaria, Ocotea], Urticaceae [Laportea]).
Not aril-like
Dry
               Pseudoanthecium. Anthocarp of the Cyperaceae, the pericarpium in a sac-like structure (Carex).
               Pseudosamara.  Anthocarp winged at one end (17+ families: Cunoniaceae [Aphanopetalum],
                    Diptercarpaceae,...