SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ec8dd5d2585c801d9920f08e6a6fce1fd014fe952e60ae07c32e35a9735b22d' 
  AND token = 'MbvRyrglIqja97eQdri5zJdhlJqhcUavqnyVVLTbHrw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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