Assessing the Diversity and Distribution Pattern of the Speciose Genus Lycocerus (Coleoptera: Cantharidae) by the Global-Scale Data

Abstract

Species richness patterns and endemism on the large-scale play a significant role in biogeography and biodiversity conservation. This study aimed to explore the diversity centers and endemic areas of a large cantharid genus Lycocerus, so as to test whether the hypothesis of montane and island systems biodiversity in previous studies was supported. In this study, a comprehensive species’ geographical database on the global scale consisting of 4,227 records for 324 Lycocerus species was compiled and analyzed. Species richness pattern was mapped into a grid-based map with a spatial resolution of 1° × 1° fishnet. An unbalanced pattern was identified, and it showed that the centers of species richness of Lycocerus were situated in Eastern Himalayas, Hengduan Mountains, Eastern Sichuan Mountains, Taiwan, and Japan. Further analyses based on two approaches, including parsimony analysis of endemicity (PAE) and endemicity analysis (EA), were applied to detect areas of endemism (AOEs) at three different grid sizes (1°, 1.5°, and 2°). Finally, a total of nine AOEs were detected, including five montane areas (Himalayan areas, Hengduan Mountains, South edge of China, Eastern China Mountains, and Eastern Sichuan Mountains), three islands (Taiwan Island, Japan, and Korean Peninsula), and one plateau (Shan Plateau), which were generally consistent with the species richness pattern. The results verify that montane and island systems have an essential role in promoting the formation of diversity centers and AOEs because of their complex topography, varied habitat and geological events.

Exploring the Species Richness Pattern and Areas of Endemism of Tenebrionidae (Coleoptera) in Xinjiang, China

“…The study of the distribution patterns of species richness and endemic areas have always been central issues in biogeography [38][39][40][41][42][43][44], which not only represent the highest degree of the historical and ecological imprint of all biological entities [45] but also play an important role in the exploration of biodiversity hotspots [46][47][48][49][50][51].…”

“…Species richness, defined as the number of species in each cell, is the most basic and important indicator for identifying biodiversity hotspots and endemic areas [52,53]. Several studies have been undertaken using species richness as a measure to understand what affects biodiversity [10,48,51,53,54]. However, because species richness is easily affected by external factors (e.g., anthropogenic factors, geographic isolation, environmental change, etc.…”

“…However, because species richness is easily affected by external factors (e.g., anthropogenic factors, geographic isolation, environmental change, etc. ), simple species richness alone cannot reflect the true level of species spatial distribution [55], and the highest level of species richness does not necessarily mean the highest level of endemism [51]. Therefore, a new index called the areas of endemism (AOEs) has also been used to explore the distribution patterns of organisms [51,53,56].…”

“…Recently, a number of biogeographic and evolutionary studies have implemented and applied AOEs to resolve practical issues [48,49,[51][52][53][56][57][58]. Although the definition of AOEs has been controversial in the past, it is now generally accepted as the distribution of two or more endemic species [59][60][61][62].…”

“…In some cases, more complete results can be obtained by combining two or multiple methods [62,71]. Among several approaches, two of them are most commonly used in exploring AOEs [51,53,56,72,73]. One approach is parsimony analysis of endemicity (PAE), which identifies ecological affinities between species by analysing species composition at local or regional scales [74,75].…”