SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b509dc2bde28b75c6093c293eb5ec71dd241f9aa3ff00c26976f4dc3d1a7b989' 
  AND token = 'yolIB5h8hnMfkQMSuhzYJ5LeICn3QV6OVyG48WZNwP4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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