You selected Rhynchospora divergens var. expansa Kük. This is a synonym for:

Accepted scientific name:
Rhynchospora divergens Chapm. ex M.A.Curtis (accepted name) 1 literature reference for Rhynchospora divergens Chapm. ex M.A.Curtis
Synonyms:
Phaeocephalum divergens (Chapm. ex M.A.Curtis) House (synonym) 1 literature reference for Phaeocephalum divergens (Chapm. ex M.A.Curtis) House
Rhynchospora divergens var. expansa Kük. (synonym) 1 literature reference for Rhynchospora divergens var. expansa Kük.
Rhynchospora lamprosperma C.Wright (synonym) 1 literature reference for Rhynchospora lamprosperma C.Wright
Rhynchospora ravenelii M.A.Curtis (synonym) 1 literature reference for Rhynchospora ravenelii M.A.Curtis
Common names: -
Classification:
Plantae
Phylum Magnoliophyta
Class Liliopsida
Order Poales
Family Cyperaceae
Genus Rhynchospora
Distribution: SE. U.S.A., SE. Mexico to Belize, Caribbean
Additional data: -
Source database: World Checklist of Selected Plant Families, 27 Nov 2009
Latest taxonomic scrutiny: Govaerts R., 21-Jun-2005
Online resource: http://apps.kew.org/wcsp/namedetail.do?accepted_id=261719&repSynonym_id=-9998&name_id=261719&status=true
CoL taxon LSID: urn:lsid:catalogueoflife.org:taxon:dd2c5cb0-29c1-102b-9a4a-00304854f820:ac2010