SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '679b1f595dbbe9b2492454725c16c08302e006594f07696e1d12872dfa675f56' 
  AND token = 'rlh978Pz4SMKkluv83kaU/GTj4KZXsWPYXHkStEcHpY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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