Friday, December 30, 2022

[Entomology • 2022] Alainites siamensis • A New Species of Alainites (Ephemeroptera: Baetidae) from Thailand


Alainites siamensis  
Phlai-ngam, Tungpairojwong & Gattolliat, 2022
 

Abstract
A new species of Baetidae, Alainites siamensis sp. nov., is described from Thailand. This new species is closely related to Alainites lingulatus Tong & Dudgeon, 2000, Alainites laetificus (Kang & Yang, 1994) and Alainites yixiani (Gui & Lu, 1999). Species delimitation based on morphological and molecular (mitochondrial COI sequences) evidence is provided. The discovery of this species confirms the wide distribution of Alainites Waltz & McCafferty, 1994 in Southeast Asia.

Key Words: distribution, diversity, mayflies, Southeast Asia, systematic

Alainites siamensis sp. nov., female larva (middle instar larva) habitus:
 A Dorsal view; B Lateral view; C Ventral view.
Scale bar: 1 mm.

Alainites siamensis sp. nov.

Diagnosis: Alainites siamensis sp. nov. is closely related to A. lingulatus, A. laetificus and A. yixiani; these species are distributed in the Southeast Asia. The new species can be separated from the other species by the following combination of characters: i) the shape of labial palp, ii) the setation on tibia, iii) the number of denticles of the claws, iv) the degree of development and spination of paraproct prolongation, v) the number of spines on distal margin of paraproct, vi) number of pairs of gills (Table 4).

Ecological notes: The larvae of Alainites siamensis sp. nov. mainly live among aquatic plants and roots of riparian plants in slow to moderately flowing streams (Fig. 6). The species seems to be rather widely distributed in the northwestern and northern Thailand, but is rare and not abundant (Fig. 7).

Etymology: The specific epithet of this species, siam (noun), refers to the old name of Thailand and to the known distribution of the species.

The sampling sites and habitats of Alainites siamensis sp. nov. larvae:
A–B Yakruae stream, Nam Nao National Park, Phetchabun Province (type locality);
C–D Stream in Mae Ra Mad District, Tak Province;
E–F Stream near the Mining Dr. Phol Kleepbuathe, Thong Pha Phum District, Kanchanaburi Province.


Sirikamon Phlai-ngam, Nisarat Tungpairojwong and Jean-Luc Gattolliat. 2022. A New Species of Alainites (Ephemeroptera, Baetidae) from Thailand. Alpine Entomology. 6: 133-146.  DOI: 10.3897/alpento.6.96284