SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '8b9ce205162c6cc126016f91fda3a61602c9dd38ee1b36b961883dc144a2b364' 
  AND token = 'ZBPNK/GCK0OpDBsvQiRlFfv+J0rCRdQEgNEDPdsefM0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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