SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0eaac49413a30466a63105f6f9544d2588ed5fe5e26b76417ead1ace97a89e96' 
  AND token = 'kaIgXzcFIHUMVaUiZpdma+zupoX/giKybmTjRkT6rqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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