SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c0b29b996298a96dedac3dad0440dfc379ab842018013bb3c1d5a8062f5b5fb2' 
  AND token = 'OcFdY7P7KDl98LzKKGaRj+qKx0v3sdmGQrSua/v55Xg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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