SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '79666051320297cbf9ca62afac8dc19ee5f326c7d64734d85bd43e12884e5476' 
  AND token = '2kFbIDWmcXwepVKjsSdnOxnVuM0zgzodjSTEPnoXrNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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