SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc38e73925f10adfa29cb518be242ce20fe7ccc44c12b20be79c6d55e1589ab4' 
  AND token = 'HWsT8ywQxGP6uWsFl7STvFXn7R4rM/+bgTHJ7Z0MLg0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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