Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'a7d4df6dced92011077eb1d72e99ac35194f8a9c4e0fb17687a2a1bd415c9607' 
  AND token = '71FWIWcP2XGj4MQelGr0iQfPkeuU8SGbnGOkFAfWclQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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