SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'c539a6f6ce1898d4057be0ee7435e46220b185d48d1bf647a27f14c032a9f40d' 
  AND token = 'wI2Bvrkx1zvLKYT5zwRxq48+t5IzP2CuLmCAZBJ2wTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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