Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '933979aaef6d28f1b543c3f924b7c9177ab91996a15771362a452cf293b27611' 
  AND token = 'XC1RdHun440GiNhrCwPD5lEU8uvivk8rhXRcbP2wVu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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