SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7573c9d3c1769d15b5d95a1867740ad427b1ef9affec6d6d1d5869190fcfa310' 
  AND token = 'AIcLl4pxIpT1IIqSTkcw+5B26OvGxbJ1vZHnSXjxOdE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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