SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16f06ef4e98272e1fd7108b731cd8fee1478357be8c5a9fcdd6f1a79cf874942' 
  AND token = 'zgX22XQH8b7w5aVkwheVlXM95g0feHsBTsW1S17W/Uc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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