Trichoptera community composition

A total of 2,748 larvae of Trichoptera were collected from the sampled streams in northern Thailand. Fortyone taxa from seven streams were identified from 24 genera and 13 families (Table 3). At the family level, the Hydropsychidae were the most numerous, accounting for 1,487 specimens (54%). The highest number of caddisfly larvae was collected at S5 (570 individuals), while the lowest number was collected at S4 (213 individuals). Marilia sumatrana Ulmer 1951 was the most abundant species collected, with 318 individuals, followed by Chimarra sp. (276 individuals), Cheumatopsyche cf. dubitans Mosely 1942 (272 individuals), and Potamyia phaidra Malicky & Chantaramongkol 1997 (in Malicky 1997) (219 individuals).

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* Larvae described in this publication.

Based on the results of the adult caddisfly species in this study, 10 species of hydropsychid larvae could be associated with identifiable adults. The 10 species of hydropsychid larvae comprised 6 genera: Amphipsyche ( A. meridiana Ulmer 1909); Cheumatopsyche ( C. copia Malicky & Chantaramongkol 1997 in Malicky 1997, C. tramota Malicky & Chantaramongkol 1997 in Malicky 1997); Hydropsyche ( Hp. camillus Malicky & Chantaramongkol 2000, Hp. askalaphos Malicky & Chantaramongkol 2000, Hp. pallipenne Banks 1938); Hydromanicus [ Hm. klanklini (Malicky & Chantaramongkol 1993) and Hm. serubabel Malicky & Chantaramongkol 1993]; Potamyia ( P. phaidra); Pseudoleptonema ( P. supalak Malicky & Chantaramongkol 1998 in Malicky 1998) (Table 3). Among the taxa identified, Hydropsyche pallipenne and H. askalaphos are described here, whereas the other eight species mentioned above have been described (Peumwarunyoo & Prommi 2013; Prommi 2016; Prommi & Permkam 2015; Prommi et al. 2006a, 2006b, 2006c) and their identities were confirmed by the metamorphotype method in this investigation. The morphological, biological, and ecological characteristics of species described in the larval stage of the fauna of Thailand are discussed below.