Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '538546dd6e2add86888a5fec54195600b633837ec8b4fe09e50f4685e1669fd9' 
  AND token = 'fjyPai6D7u4UTf3U3iQsueZirBNuBNfPwRnN/RqquYI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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