SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '0bebe99cd4e95b6c921466a7db1f11954cf1bff0629357e5b1cddb36c733adce' 
  AND token = 'RaKic6M8sWG9/kTVpcccDRuYmB15TP7jDCThML5L4D4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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