SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9af68bb6afab7832b1ad3795c0fa3faa52846c9cf64e17c50b0b629439e14591' 
  AND token = 'TaSabn9jV3rYjBdQaBVYnwi6bRglhyXh6FczpGdcDcc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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