SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58555bd35f5d7f4c2ed2d74ea75de207c6941e22d08e5ce04e4e781a5106bd44' 
  AND token = '40nr521Uk/EtRIwoaJLPX5tUtytJNwgH0HRa3eWgTZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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