SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ff8bda3ac7c0c83ffa86a52c0b114b3c61ec33c8beec3d102129d5d85eda09fa' 
  AND token = 'bSmcUAVVyisJlbigpAYBCATywCsDFnFHl0g9Srd1FR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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