朝雲細蟌學名 Ischunra aurora v. Ischnura rubilio

Does Taiwan's Ischnura aurora remain as it is or be Ischnura rubilio?

「朝雲細蟌」學名應該是Ischunra aurora 還是 Ischnura rubilio？

A paper concludes that all the I. aurora found within the Australo-Pacific distribution area cluster together in a separate clade, the real I. aurora, and suggested those previously thought to be I. aurora in Asia should be I. rubilio.(1)

不久前有一份論文總結：分布在南太平洋 (紐西蘭、澳洲、玻里尼西亞) 的才是真正的Ischnura aurora，其他亞洲的I. aurora 則應是Ischnura rubilio。(1)

An identification key for the separation between I. rubilio and I. aurora was provided in the publication by Lorenzo-Carballa et al. (2022). The simplest one is the blue marking on S8: (1)
I. rubilio: entirely blue dorsally
I. aurora: with only posterior half blue dorsally

Lorenzo-Carballa 等人提出一套分辨 I. aurora 和 I. rubilio 的檢索方法，其中做簡單的分辨指標是第八腹節的藍色部分。(1)
I. rubilio 第八腹節背面全藍
I. aurora 第八腹節後半背面藍

Checking these 2 guidebooks of Taiwan's odonata in which the photos of I. aurora show that only posterior half of S8 is blue.

查閱兩本台灣的蜻蜓圖鑑發現：台灣的朝雲細蟌的照片都是第八腹節只有後半背面藍色。

1. 臺灣蜻蛉目昆蟲檢索圖鑑 (An illustrated identification guide to the Odonata of Taiwan) 林斯正、楊平世 / 特有生物保育中心 / 2016.12 (p.157)
2. 台灣120種蜻蜓圖鑑 曹美華 / 社團法人台北市野鳥學會 / 2005.1. (p.27)

Meanwhile, the data of I. aurora logged in Taiwan on iNaturalist also show only with posterior half blue on S8. (2)

同時，在 iNat 上收集到的觀察記錄也是如此：第八腹節只有後半背面藍色。(2)

Unfortunately, there is no record (of I. aurora) on iNat observed in Japan, but only one in Philippines (with 7 photos), which has posterior half blue S8.

可惜，在 iNat 上沒有收集到日本 I. aurora 「朝雲細蟌」的觀察記錄；菲律賓的僅有一筆，同樣是第八腹節背面後半藍色。
https://www.inaturalist.org/observations/109280832

This is also communicated with the webmaster of Japanese odonata website and his findings in response to the question is published on his website (& he is the person pointed out the id key of S8 stated in the paper and used it to screen out): those photos of the samples taken in Japan all demonstrate the same feature, black S8 with posterior half blue, but one in doubt, the sample collected on Ishigaki Island because photo of that sample (collected by Asahina in 1964) is not immediately available.

這問題也請教一位日本蜻蜓網站的站長(日本也有Ischunra aurora，他們叫キバライトトンボ ，查找圖鑑看S8的方法也是他提出來的，我只是仿效。)，他對Lorenzo-Carballa 等人對於 I. rubilio 分類的回應寫在網上，キバライトトンボ (I. aurora) 介紹中的＜特記事項＞。他指出一些日本採集標本和圖鑑上的照片都是第八腹節背面後半藍色，只有在石垣島採的標本無法確定。
https://www.odonata.jp/03imago/Coenagrionidae/Ischnura/aurora/index.html

The paper mentioned the samples collected from China is close to I. rubilio. In Chinese dragonfly guidebook published by Dr. Zhang(3), the distribution of I. aurora is quite limited, no costal provinces but Yunnan only. Just as stated in the paper, the photo shows I. aurora with full blue S8, which should be I. rubilio.

該論文提到在中國採到的標本都比較接近 I rubilio。而2019年张浩淼博士出版的圖鑑中「黄腹异痣蟌 」Ischnura aurora (Brauer, 1865) 的分布只有寫到云南，沿海省份都沒有分布；照片中云南產的第八腹節是全藍。

There are plenty of records of HKG on iNat; unfortunately, I. aurora is not listed in HKG. Though it's listed in Hainan, there is not any sighting report after 1930.(4)

iNat 上有很多香港的觀察記錄，可惜「朝雲細蟌」 I. aurora 並沒有分布在香港，雖然海南到曾有過記錄，但是自從 1930 後就沒有任何記錄了。(4)

Besides, I. aurora is not listed in Korea, either.(5)

此外，韓國也沒有 I. aurora. (5)

From these findings, we understand that there is a huge void in distribution between Asian continental sp. and Oceanic ones. It's quite safe to assume that those continental ones occurring from India to Yunnan belong to one "group" and those oceanic, another, from Australia, Fiji all the way to Philippines, Taiwan and Japan. Those continental ones are of I. rubilio, and oceanic, I. aurora.

從這些發現我們可以知道：在亞州大陸分布的「朝雲細蟌」 I. aurora 以及 太平洋地區分布的「朝雲細蟌」 I. aurora 之間有很大一片空白。我想我們可以說：亞州大陸分布的「朝雲細蟌」，從印度一直到雲南是一組，然後太平洋這邊，從澳洲、斐濟、一路經過菲律賓、台灣、日本的是另一組。前者大陸產的就是 I. rubilio，後者是 I. aurora.

Although it's not yet sure if the sample collected in Ishigaki Island is indeed I. aurora or should be I. rubilio, the chance of being the later is quite little. The distance btw the Island to northern Taiwan is about 240km, but it's 2000km from Yunnan & there are sea and high mountains in between.

雖然不知道朝比奈博士 1964 年在石垣島採的標本是哪一種，但是會跟大陸產的一樣的機率應該很低，畢竟石垣島到北台灣只有200公里，而到云南是2,000公里，而且這中間還有海洋和高山。

Most likely, Taiwan's Ischnura aurora just remains as it is, need not to change taxa.

十之八九，「朝雲細蟌」學名應該還會是 Ischunra aurora，不用改變。

備註 / Remarks：
(1) Lorenzo-Carballa, M. O., Sanmartín-Villar, I, Cordero-Rivera, A. 2022. Molecular and morphological analyses support different taxonomic units for Asian and Australo-Pacific forms of Ischnura aurora (Odonata, Coenagrionidae). Diversity 14: 606. https://www.mdpi.com/1424-2818/14/8/606/htm
(2) https://www.inaturalist.org/observations?project_id=15085&taxon_id=103480&place_id=any&verifiable=any
(3) p. 1335, 中国蜻蜓大图鉴 ISBN：978-7-5689-1037-8 作者：张浩淼 / 重慶大學出版社 / 2019-01-10
(4) p. 188- p.189, 蜻蟌之地-海南蜻蜓图鉴 (A Field Guide to the Dragonflies of Hainan) 作者：韦庚武(Graham REELS)、张浩淼 (ZHANG Haomiao) / 中國林業出版社 / 2015/09/01
(5) Odonata list of Korea https://terms.naver.com/entry.naver?docId=2427489&categoryId=51361&cid=42478

last edited 04:43pm, Sept 12, 2022 (Mon)

Julkaistu syyskuu 12, 2022 03:27 AP. käyttäjältä aru