There are more than 20 different
Fragaria species worldwide. A number of other species have been proposed, some of which are now recognized as subspecies. One key to the classification of strawberry species is that they vary in the number of
chromosomes. They all have seven basic
types of chromosomes, but exhibit different
polyploidy. Some species are diploid, having two sets of the seven chromosomes (14 chromosomes total), but others are tetraploid (four sets, 28 chromosomes total), hexaploid (six sets, 42 chromosomes total), octoploid (eight sets, 56 chromosomes total), or decaploid (ten sets, 70 chromosomes total). As a rough rule (with exceptions), strawberry species with more chromosomes tend to be more robust and produce larger plants with larger berries. The oldest fossils confidently classifiable as
Fragaria are from the
Miocene of Poland. Fossilised
Fragaria achenes are also known from the
Pliocene of China.
Diploid species '', a species from the Himalayas ''), a Northern Hemisphere species '', an Asian species '') from
Sosnovka, Penza Oblast, Russia '' fruit photographed in
Keila,
Estonia •
Fragaria × bifera Duchesne -
F. vesca ×
F. viridis (Europe) •
Fragaria bucharica Losinsk. (China) •
Fragaria chinensis Losinsk (China) •
Fragaria daltoniana J.Gay (Himalayas) •
Fragaria emeiensis Jia J. Lei (China) •
Fragaria gracilis Losinsk. (China) •
Fragaria hayatae Makino (Taiwan) •
Fragaria iinumae Makino (East Russia, Japan) •
Fragaria mandshurica Staudt (China) •
Fragaria nilgerrensis Schlecht. ex J.Gay (
South and
Southeast Asia) •
Fragaria nipponica Makino (Korea, Japan) •
Fragaria nubicola Lindl. ex
Lacaita (
Himalayas) •
Fragaria pentaphylla Losinsk. (China) •
Fragaria vesca L. - woodland strawberry (
Northern Hemisphere) •
Fragaria viridis Duchesne (Europe, Central Asia)
Tetraploid species •
Fragaria corymbosa Losinsk. (northern China) •
Fragaria × intermedia (Bach) Beck (Europe) •
Fragaria moupinensis Cardot (China) •
Fragaria orientalis Losinsk. (Eastern Asia, Eastern Siberia) •
Fragaria tibetica Staudt & Dickoré (China)
Pentaploid hybrids •
Fragaria × bringhurstii Staudt (
coast of California)
Hexaploid species •
Fragaria moschata Duchesne - musk strawberry (Europe)
Octoploid species and hybrids •
Fragaria × ananassa Duchesne ex Rozier - garden strawberry, pineapple strawberry •
Fragaria chiloensis (
L.) Mill. - beach strawberry (Western
Americas) •
Fragaria chiloensis subsp.
chiloensis forma
chiloensis •
Fragaria chiloensis subsp.
chiloensis forma
patagonica (
Argentina,
Chile) •
Fragaria chiloensis subsp.
lucida (E. Vilm. ex Gay) Staudt (
coast of
British Columbia,
Washington,
Oregon,
California) •
Fragaria chiloensis subsp.
pacifica Staudt (coast of
Alaska, British Columbia, Washington, Oregon, California) •
Fragaria chiloensis subsp.
sandwicensis (
Decne.) Staudt -
ōhelo papa (
Hawaii) •
Fragaria virginiana Mill. - Virginia strawberry (
North America)
Decaploid species and hybrids •
Fragaria cascadensis K.E. Hummer (Cascade Mountains in
Oregon) •
Fragaria iturupensis Staudt - Iturup strawberry (
Iturup,
Kuril Islands) •
Fragaria × Comarum hybrids •
Fragaria × vescana Polyploidy unknown •
Fragaria tayulinensis S.S.Ying (Taiwan)
Uncategorized hybrids • 'Lipstick' (
Fragaria ×
Comarum hybrid), red-flowered runnering ornamental, sparse small globular fruits. •
Fragaria vesca and certain other diploid species can be hybridized and produce fertile offspring (although
Fragaria nilgerrensis appears less compatible). •
Fragaria moschata can hybridize with diploid species such as
Fragaria viridis and
Fragaria nubicola but producing a lower proportion of viable seeds. •
Fragaria moschata can hybridize with
Fragaria × ananassa. ==Ecology==