SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a0861fafe5aea1e5d1bb17504bed490cefd3257c628758ec1661046540546bb' 
  AND token = 'BkvTDdpHydVJ9kMsf1hfmHuGVkfe0HKwE8EIFm0yuS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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