Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy.
J Insect Sci. 2024 Sep 1;24(5). doi: 10.1093/jisesa/ieae089.
Longitarsus candidulus (Foudras) is a thermophilic flea beetle species widely distributed in the Mediterranean Basin and associated with Daphne gnidium L. and Thymelaea hirsuta (L.). Longitarsus laureolae Biondi and Longitarsus leonardii Doguet, phylogenetically closely related to L. candidulus, show together a peculiar and rare disjunct distribution along the central-southern Apennines and the Cantabrian-Pyrenean mountain system, respectively. Both are associated with Daphne laureola L. in mesophilic habitats. We used "ecological niche modeling" to infer the Pleistocene dynamics in the distribution of the three flea beetle species and their host plants. We interpreted their current distributions, paying particular attention to the presumed time of species divergence as inferred from recent studies. The differentiation of L. laureolae and L. leonardii from L. candidulus likely represents a response to the marked climatic changes during the Late Pliocene. Such a split was likely associated with a trophic niche shift of the laureolae/leonardii ancestor towards the typically mesophilic host plant D. laureola. The subsequent split between L. laureolae and L. leonardii, possibly due at first to the niche competition, was then boosted by an allopatric divergence during the Middle Pleistocene, likely caused by a large area of low environmental suitability for both species, mainly located between the northern Apennines and the south-western Alps.
长角长足虻（Foudras）是一种嗜热的跳蚤甲虫物种，广泛分布在地中海盆地，与 Daphne gnidium L. 和 Thymelaea hirsuta（L.）有关。与 L. candidulus 在系统发育上密切相关的 Longitarsus laureolae Biondi 和 Longitarsus leonardii Doguet，分别沿中南部亚平宁山脉和坎塔布连-比利牛斯山脉系统呈独特而罕见的间断分布。两者都与喜温生境中的 Daphne laureola L. 有关。我们使用“生态位模型”来推断这三种跳蚤甲虫及其宿主植物在更新世分布的动态。我们解释了它们目前的分布情况，特别注意了根据最近的研究推断出的物种分化时间。L. laureolae 和 L. leonardii 与 L. candidulus 的分化可能代表了对上新世晚期气候变化的响应。这种分裂可能与 laureola/leonardii 祖先的营养生态位向典型的喜温宿主植物 D. laureola 的转移有关。随后 L. laureolae 和 L. leonardii 之间的分裂，可能首先是由于生态位竞争，然后在中更新世由于大面积的低环境适宜性而发生地理隔离，这主要发生在北部亚平宁山脉和西南阿尔卑斯山之间。
