SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '9c32b811575c274ab3851949d961d09f861cbd3810190cfa7895f3b51b11b84e' 
  AND token = 'MHqo/xApmzG37bDJVaskegr3WF1UHgnp3+mnoyqNBmg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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