SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '39dd168c5ae5a0fa778bef5948997ee9a4e23795c37a9fd444b1a50c2527762d' 
  AND token = 'bvEmC1BwY+LSgzWbeq77PKbm0e/nOb1wzL16PiqSIu0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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