SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e5bb60552175baf07abfb9e3b65390ff2132f223abf1a95dc5b7f23bd6987bea' 
  AND token = 'D5k1Kfyk3WtaKzEjyijCvyiFAhKcmkvMf4drhejux90=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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