SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3139b572db2d5169a0ad08ae5e87cc725fd75270883c43e07acc5ba49d050b7' 
  AND token = 'dGGTUOuUlyKQgk+CT3YOgMkqqahR18BqZl6jSZMosqo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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