Biology Department, Section Vertebrates, Royal Museum for Central Africa, Tervuren, Belgium.
KU Leuven, Ecology, Evolution and Biodiversity Conservation, Charles Deberiotstraat 32, Leuven, Belgium.
J Fish Biol. 2020 May;96(5):1202-1217. doi: 10.1111/jfb.14107. Epub 2019 Oct 29.
Lake Edward, East Africa, harbours a largely understudied assemblage of haplochromine cichlids that displays a range of adaptions to various specialised trophic niches. In this system, we discovered specimens of Haplochromis with morphologies similar to those of oral-mollusc shellers from Lake Victoria. These morphologies are characterised by short oral jaws with stout teeth that are used either to crush molluscs or to grab the soft bodies of snails and wrench them out of their shells. A morphometric study on 47 specimens from Lake Edward revealed the presence of three new species with an oral-shelling morphology: Haplochromis concilians sp. nov., H. erutus sp. nov. and H. planus sp. nov. All three species are formally described. Stomach-content observations confirmed an opportunistic oral-shelling ecology for H. concilians sp. nov. and H. erutus sp. nov. Within H. planus sp. nov., only large specimens displayed a specialised oral-shelling morphology, but their stomachs were nearly empty, while small specimens consumed mainly Ostracoda and Hydrachnidia. Remarkably, the three species differed considerably in morphology from each other, but they each resembled oral-sheller species from Lake Victoria.
东非爱德华湖拥有大量研究不足的haplochromine 慈鲷组合，这些慈鲷表现出各种适应不同专门营养位的特征。在这个系统中，我们发现了爱德华湖中有一些类似于维多利亚湖食贝类物种的形态的 Haplochromis 标本。这些形态的特点是短而粗壮的口腔颌骨，上面有坚固的牙齿，用于压碎贝类或抓住蜗牛的柔软身体并将其从壳中拔出。对来自爱德华湖的 47 个标本进行的形态测量学研究揭示了三种具有食贝类形态的新物种：Haplochromis concilians sp. nov.、H. erutus sp. nov. 和 H. planus sp. nov.。所有这三个物种都被正式描述。胃内容物观察证实了 H. concilians sp. nov. 和 H. erutus sp. nov. 具有机会主义的食贝类生态。在 H. planus sp. nov. 中，只有大标本表现出专门的食贝类形态，但它们的胃几乎是空的，而小标本主要以介形类和水螨为食。值得注意的是，这三个物种在形态上彼此差异很大，但它们都类似于维多利亚湖的食贝类物种。
