SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a47ed99b2e704f22ef0518539b8d8977c25f647f4f63822d34a51b56d000a30e' 
  AND token = '32OScHNjl86LcFQmjOFiiY4EBdZzEueJsDQRsLEvq8s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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