SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab2e71546c7811b4d9b186dd21261225504b5502b499ff81189e523bb08cf91c' 
  AND token = '2zDBMKhpgURjORibJiEoZlscmF6zTcto3ZLeZWa0LVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}