- genus calendula
- genus calidris
- genus calla
- genus calliandra
- genus callicebus
- genus callimorpha
- genus callinectes
- genus calliophis
- genus calliphora
- genus callirhoe
- genus callisaurus
- genus callistephus
- genus callithrix
- genus callitriche
- genus callitris
- genus callophis
- genus callorhinus
- genus calluna
- genus calocarpum
- genus calocedrus
- genus calochortus
- genus calophyllum
- genus calopogon
- genus calosoma
- genus caltha
- genus calvatia
- genus calycanthus
- genus calycophyllum
- genus calymmatobacterium
- genus calypso
- genus calystegia
- genus camassia
- genus cambarus
- genus camelina
- genus camellia
- genus camelus
- genus campanula
- genus campephilus
- genus camponotus
- genus camptosorus
- genus campyloneurum
- genus campylorhynchus
- genus canachites
- genus cananga
- genus canangium
- genus canavalia
- genus cancer
- genus candida
- genus canella
- genus canis
- genus canna
- genus cannabis
- genus cantharellus
- genus capella
- genus capparis
- genus capra
- genus caprella
- genus capreolus
- genus capricornis
- genus caprimulgus
- genus capros
- genus capsella
- genus capsicum
- genus caragana
- genus caranx
- genus carassius
- genus carcharhinus
- genus carcharias
- genus carcharodon
- genus cardamine
- genus cardiospermum
- genus cardium
- genus carduelis
- genus carduus
- genus caretta
- genus carex
- genus cariama
- genus carica
- genus carissa
- genus carlina
- genus carnegiea
- genus carpenteria
- genus carphophis
- genus carpinus
- genus carpobrotus
- genus carpocapsa
- genus carpodacus
- genus carthamus
- genus carum
- genus carya
- genus caryocar
- genus caryota
- genus casmerodius
- genus cassia
- genus cassiope
- genus castanea
- genus castanopsis
- genus castanospermum
- genus castilleia
- genus castilleja
- genus castor
- genus castoroides
- genus casuarina
- genus casuarius
- genus catacala
- genus catalpa
- genus catananche
- genus catasetum
- genus catha
- genus catharacta
- genus catharanthus
- genus cathartes
- genus cathaya
- genus catoptrophorus
- genus catostomus
- genus cattleya
- genus caulophyllum
- genus cavia
- genus cebuella
- genus cebus
- genus cecropia
- genus cedrela
- genus cedrus
- genus ceiba
- genus celastrus
- genus celosia
- genus celtis
- genus cenchrus
- genus centaurea
- genus centaurium
- genus centranthus
- genus centrocercus
- genus centrolobium
- genus centropomus
- genus centropristis
- genus centropus
- genus centrosema
- genus centunculus
- genus cephalanthera
- genus cephalopterus
- genus cephalotaxus
- genus cephalotus
- genus cepphus
- genus cerapteryx
- genus cerastes
- genus cerastium
- genus ceratitis
- genus ceratodus
- genus ceratonia
- genus ceratopetalum
- genus ceratophyllum
- genus ceratopogon
- genus ceratopteris
- genus ceratosaurus
- genus ceratostomella
- genus ceratotherium
- genus ceratozamia
- genus cercidiphyllum
- genus cercidium
- genus cercis
- genus cercocebus
- genus cercopithecus
- genus cercospora
- genus cercosporella
- genus cereus
- genus ceroxylon
- genus certhia
- genus cervus
- genus ceryle
- genus cestrum
- genus cestum
- genus ceterach
- genus cetonia
- genus cetorhinus
- genus cetraria
- genus chaenactis
- genus chaenomeles
- genus chaenopsis
- genus chaetodipterus
- genus chaetodon
- genus chalcis
- genus chalcostigma
- genus chamaea
- genus chamaecrista
- genus chamaecyparis
- genus chamaecytisus
- genus chamaedaphne
- genus chamaeleo
- genus chamaeleon
- genus chamaemelum
- genus chara
- genus charadrius
- genus charina
- genus charronia
- genus chateura
- genus chauna
- genus cheilanthes
- genus cheiranthus
- genus chelidonium
- genus chelifer