SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47fbbac2e052652af3b83c5429dfaf1df5b479476d443d9d08742ec52f3fe817' 
  AND token = 'HqYBYSswwe/c0mPi+4U6BuhURHFSJpgNymST9n4ZkoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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