You selected Haworthia cooperi var. gracilis (Poelln.) M.B.Bayer. This is a synonym for:

Accepted scientific name:
Haworthia gracilis Poelln. (accepted name) 1 literature reference for Haworthia gracilis Poelln.
Synonyms:
Haworthia arachnoidea var. gracilis (Poelln.) Halda (synonym) 1 literature reference for Haworthia arachnoidea var. gracilis (Poelln.) Halda
Haworthia cooperi var. gracilis (Poelln.) M.B.Bayer (synonym) 1 literature reference for Haworthia cooperi var. gracilis (Poelln.) M.B.Bayer
Infraspecific taxon: Haworthia gracilis var. gracilis
Haworthia gracilis var. isabellae (Poelln.) M.B.Bayer
Haworthia gracilis var. picturata M.B.Bayer
Haworthia gracilis var. tenera (Poelln.) M.B.Bayer
Haworthia gracilis var. viridis M.B.Bayer
Common names: -
Classification:
Plantae
Phylum Magnoliophyta
Class Liliopsida
Order Asparagales
Family Xanthorrhoeaceae
Genus Haworthia
Distribution: S. Cape Prov.
Additional data: -
Source database: World Checklist of Selected Plant Families, 27 Nov 2009
Latest taxonomic scrutiny: Govaerts R., 09-Jul-2004
Online resource: http://apps.kew.org/wcsp/namedetail.do?accepted_id=277163&repSynonym_id=-9998&name_id=277163&status=true
CoL taxon LSID: urn:lsid:catalogueoflife.org:taxon:ee6379a0-29c1-102b-9a4a-00304854f820:ac2010