Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d8b75fd8b79fff9a365ae0cf3b6f874b38f5d3eb7bdd03f35dbee6f325173aa' 
  AND token = 'HlRQVg3/zba9Hk5OHGE/RgjCb+b/9saOZG0eJM/zcuM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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