SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3612533fb0373c4852bdb52b81bc840614f99bf2c54b30628e0543a040dcb467' 
  AND token = 'B/kEsUQyFLUxw4BWXHXJrDvpyx6aBsGkyM4dowiwE6Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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