Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b49fe2fe76227425f6495d38c6257aefd2c2fb1c1eb24b86be76b3ad8e6b9816' 
  AND token = 'PM5j6PkWYoSGGtkky+SZb2DM5E6qGOAmKyWDUrUGUNM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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