SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '893895c819353eb6db388a1520744eb697dbcf603b44827adda95a33944f4704' 
  AND token = 'Fny0XsY+iH7t6jHS8MZtYI2yX5V/cSoS2npff+W3xq0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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