SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '663cf5a02ffbe862c6a49e55c6b3758cd30b9b624e1fb032d4cd338f4e844bdc' 
  AND token = 'BU/kww0UCJTHkFIdz+q6aDVj9PXwKmGeHOZCoHINRqs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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