SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '48f9fb720df5650ff98880ec1d53c3e6fa41b9dfd83b70e111147e30304cd002' 
  AND token = 'aXzmGcgLtI/DEKYssQH1Hc8LicDXPMsKHLPJ+EKMh/0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}