SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '79f3d0b1e8da0fea2c2b8ddf6d68c0ba18634c6c49ae45db6a44b2088cb13a2c' 
  AND token = 'kwv1eZCrKmjBNrDHumY4kljcVI0GA6jlY8RAE6K67oc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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