1. Having a lower than normal ceiling

See also: ceilinged

• genus Rangifer
• genus Ranunculus
• genus Raoulia
• genus Raphanus
• genus Raphia
• genus Raphicerus
• genus Raphus
• genus Ratibida
• genus Rattus
• genus Rauvolfia
• genus Rauwolfia
• genus Ravenala
• genus Recurvirostra
• genus Regalecus
• genus Regnellidium
• genus Regulus
• genus Reithrodontomys
• genus Remilegia
• genus Reseda
• genus Retama
• genus Reticulitermes
• genus Retrophyllum
• genus Rhagoletis
• genus Rhamnus
• genus Rhapis