SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1fea54fcce1e6580f872c1846c54bb1d5ba1b3e65f6efb5b4991bec1c997b3d' 
  AND token = 'uXKD8TX9CYRJZM33xfY82AoSzBB1ehhBVW6JwB6jW7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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