SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'abccedc075f371bb43b1dced19f28673a74eaf1dcdce628de0273279aeed297b' 
  AND token = 'lMJBdF6E85aLFTeGJk62JEfJYyqopF1dTYCDO1SkkeA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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