SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8ba8da13fcbbcd20c0d60a06957ceccc96715aeeac62f4e072a4f7b3997e715' 
  AND token = 'huGj2C0uNSkVwmjqmNorxaPwUQtpY01aveWy1KU9XBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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