SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bb8d5a37df640f53d95675299c25176a674b0c7ebd3e373c57f81c2f6f2ba5e0' 
  AND token = 'HhZfmCcpVuqHBTQR+YjbOhs3lh3pp0SYo9/AoGIzwNA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00102

JSON explain

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