Sandbox

SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a3c8517b9bc7b1d0e26a1053c25fb2c7d98a661fca6ea0aef151424d79a1ad5d' 
  AND token = 'uuUtnFKR24XMlgRVVSAuXVlxFdemmseSiGLINJjP5sI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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