SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd559332d30b8485f5c502beaa40005168b4c309adaa70b4c365e553ccc28daf5' 
  AND token = 'tm3Oj6I8cXQOkvn+BHGTynEjc2GkZmO/d41TA+9VBKw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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