SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5efdf30861a4510dd3725f9614430554650bbeb55d12e1f1b15126a1c6a30b18' 
  AND token = 'rqVg/gYesHwHASUaSOlUk2WjrDsSamu33YrkNMz6x+Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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