SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0958d8b9b6231884601b7428086cb4a230576d544e4e4b9aa2293f7cec8ddf54' 
  AND token = 'BXv5zVAqlIYnt+H/udfbb+ifr6Bx/PFOajXuAHTyXmc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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