SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4abc4fa7192f2319efd2f144055902f7dffba71eb9deed1d76bfa09e93abfb55' 
  AND token = 'wYKVS+NjuYr4FOWw0bsDabbRrtEFhuAdeWe55jbqZsk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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