SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ed32da64153da3afadce0d6384c0d23dfd684d5f175ae229ead0cec1c930ceab' 
  AND token = 'wkPyAKqax4PWk+Rr2HnOwpbaFSXMkXiNDkoHSNxuTwI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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