SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '71d380dedc1454989420d1fd200e652083f18e45e357f971c4caac6ab7ad5931' 
  AND token = 'r+zymRPssf3GIc/WgGaBjBNXVcTI327KFsxsF4sUhBk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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