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| Ryukyuaphaenops pulcherrimus Kazuki, Showtaro, Sohei, Hisao & Shinzaburo, 2023 |
Abstract
A new genus and new species of Trechina (Coleoptera: Carabidae: Trechinae: Trechini), Ryukyuaphaenops pulcherrimus gen. & sp. nov. is described from the Ryukyu Archipelago, Japan. This is the first troglomorphic Carabidae in the Ryukyus and probably the most cave-adapted beetle in Japan. Interestingly, our observations suggest that this new trechine beetle is not similar to any genera of Trechina distributed in Kyushu and Taiwan, which are geographically close to the Ryukyu Archipelago, but is more similar to several aphaenopsian genera distributed in the inland of China. The genetic diversity of the new species is discussed based on mitochondrial DNA (COI-5’, COI-3’, 16S).
Key words: Coleoptera, Carabidae, Trechini, Trechina, biospeleology, DNA barcoding, haplotype network, new genus, new species, subterranean fauna, taxonomy, troglobiont, Okinawa-jima Island, Ryukyus, Oriental Region
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| Habitus of Ryukyuaphaenops pulcherrimus gen. & sp. nov., holotype male (KSES00004), dorsal (a) and lateral (b) views. |
Ryukyuaphaenops gen. nov.
Japanese name: リュウキュウアシナガメクラチビゴミムシ属
Type species. Ryukyuaphaenops pulcherrimus sp. nov., here designated.
Diagnosis. Ryukyuaphaenops gen. nov. is distinguished from all known genera of Trechina in the world by the following combination of characteristics: 1) aphaenopsian facies; 2) both dorsal and ventral body surfaces sparsely covered with microscopic hairs (Fig. 24); 3) right mandible seemingly bidentate though actually tridentate, due to middle tooth frequently absent (Figs 4, 5b); 4) mentum fused with submentum; 5) submentum multisetose; 6) labial palpomere 2 ...
Etymology. A combination of “Ryukyu” and “Aphaenops”. “Ryukyu [琉球]” refers to the range of the new trechine beetle. Aphaenops Bonvouioir, 1862 is a generic name of the famous Pyrenean trechine beetle with a strongly developed troglomorphism and is also traditionally used as root of the generic name of other strongly troglomorphic (aphaenopsian) trechines. Gender is masculine.
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| Habitat of type locality (25–27) and living individual (28) of Ryukyuaphaenops pulcherrimus gen. & sp. nov. 25 – Mt. Ufugushikumui; 26 – entrance of Ufugushikumui-abu-dai-ichi Cave; 27 – inside of Ufugushikumui-abu-dai-ichi Cave; 28 – living individual at the wall face of Ufugushikumui-abu-dai-ichi Cave. |
Ryukyuaphaenops pulcherrimus sp. nov.
Japanese name: オキナワアシナガメクラチビゴミムシ
Etymology. The specific name is derived from the superlative of the Latin adjective pulcher, meaning the most beautiful; adjective.
Distribution. Japan: Okinawa-jima Island in the Ryukyus (Figs 1, 2) (known only from three pit caves in the Motobu Peninsula).
Sugaya Kazuki, Kakizoe Showtaro, Ooka Sohei, Tamura Hisao and Sone Shinzaburo. 2023. Discovery of A Troglomorphic trechine Beetle from the Ryukyu Archipelago, Southwestern Japan (Coleoptera: Carabidae: Trechinae). Acta Entomologica Musei Nationalis Pragae. 63(2): 323-340. DOI: 10.37520/aemnp.2023.020
