Frist record of Protohermes stigmosus Liu, Hayashi & Yang (Megaloptera: Corydalidae: Corydalinae) in Thailand with the first description of female
The dobsonfly genus Protohermes van der Weele, 1907 (Megaloptera: Corydalidae: Corydalinae) is the most species-rich group in the order Megaloptera with 89 species of the genus being known. The genus is mainly distributed in the Oriental region (87 spp.), and two species are distributed in the Palaearctic region (Martins et al. 2022). Adult Protohermes are morphologically characterized by the forewing with anterior branch of A2 vein partly fused with stem of A1 vein, and the presence of yellow or white round markings on wings in most species (Yang & Liu 2010). Thailand is one of the most interesting regions for discovery of megalopterans, because it is a biodiversity hotspot due to its rich diversity and high endemism (Myers et al. 2000; Plant 2014; The Sustainability Consortium WRI 2019). The country is composed of Indochina and Sundaic subregions, which has been described as a zoogeographical crossroads or natural gateway from North to South (Luangjame et al. 1997). Recently, 21 species of Megaloptera were recorded in Thailand (Piraonapicha et al. 2021a). The previously reported Megaloptera fauna of Thailand includes five unidentified Protohermes and two named species: Protohermes furcatus Liu, Hayashi & Yang, 2008 from Chiang Mai Province, and Protohermes triangulatus Liu, Hayashi & Yang, 2007 from Chiang Rai, Chiang Mai, Nan Provinces (see also Liu et al. 2008, 2009; Piraonapicha et al. 2021a). Protohermes stigmosus Liu, Hayashi & Yang, 2007 was previously known only from the type locality (Xishuangbanna, Yunnan Province, China) by a single male (Liu et al. 2007). The species was classified into the Protohermes costalis species group because it has widely separated ocelli and a subcylindrical male ectoproct bearing a ventral tuft (Liu et al. 2007). Our recent survey of Megaloptera from Bo Kluea District, Nan Province in northern Thailand found an interesting species of Protohermes. Having carefully compared the specimens of this species with the type material of closely related species, we concluded that this species is P. stigmosus, a new species record from Thailand. We used the standard DNA barcode from the mitochondrial COI gene to associate the male and female of this species successfully. The barcoding regions of related species with P. stigmosus i.e. P. triangulatus and P. furcatus were also sequenced to construct the tree. All examined non-type materials are deposited in the Thailand Natural History Museum of the National Science Museum, Pathum Thani (THNHM). In the present paper, the adult male is redescribed based on Thai specimen, and female of the species is described for the first time.