Ancestral species:
Citrus maxima – Pomelo
Citrus medica – Citron
Citrus reticulata – Mandarin orange
Citrus micrantha – a papeda
Citrus hystrix – Kaffir lime
Citrus cavaleriei - Ichang papeda
Citrus japonica - Kumquat

Important hybrids:
Citrus × aurantiifolia – Key lime
Citrus × aurantium – Bitter orange
Citrus × latifolia – Persian lime
Citrus × limon – Lemon
Citrus × limonia – Rangpur
Citrus × paradisi – Grapefruit
Citrus × sinensis – Sweet orange
Citrus × tangerina – Tangerine
See also below for other species and hybrids.

Eremocitrus
Microcitrus