Thi Kim Thu Cao

A Rare Tropical Stonefly Brahmana flavomarginata (Plecoptera: Perlidae: Acroneuriinae) from Vietnam

The perlid stonefly Brahmana flavomarginata Wu, originally described from China from the male adult, is described using reared male and female adults and nymphs from Vietnam. The male adult of B. flavomarginata is distinguished from its congeners by the blackish-brown body color and distinct head marking, hemitergal triangular chitin plates, and a median semicircular smooth subgenital plate (hammer) on the abdominal sternum IX. The female adult has a large and round subgenital plate which extends to the posterior margin of the abdominal sternum X. The nymph can be distinguished by the relatively small compound eyes and the body covered by many long stout setae and short golden brown hair-like setae. This species is known in southwestern China (Yunnan Province) and northern Vietnam (Lao Cai Province, Cao Bang Province).

New Species of Acroneuria (Plecoptera: Perlidae: Acroneuriinae) from Tropical Southeast Asia

Abstract Two new species of perlid stoneflies, Acroneuria bachma n. sp. and A. magnifica n. sp., are described from tropical Vietnam. Descriptions of these species are given based on male and female adults, nymphs, and eggs. The adult of A. bachma is distinguished by the presence of a large dark brown marking in the interocellar area and by the absence of patches of sensilla basiconica on the 9th abdominal tergum; the nymph is distinguished by the presence of a narrow and complete M-line marking on head and by the absence of gills on paraprocts. The adult of A. magnifica is distinguished by presence of a distinct light-yellow M-line marking on head and patches of sensilla basiconica which are sparsely distributed on the 9th abdominal tergum; the nymph is distinguished by the presence of an incomplete M-line marking on head and gills on paraprocts. Line-drawings and macro-photographs of the diagnostic characters are provided. Adult and nymphal keys to Southeast Asian species of Acroneuria are also provided.

Togoperla thinhi, a new stonefly from central Vietnam (Plecoptera: Perlidae)

Abstract A new and rare perlid stonefly, Togoperla thinhi n. sp., is described from male and female adults and egg specimens from tropical central Vietnam. The male adult of T. thinhi n. sp. can be distinguished from other congeners by the distinct head markings, bilobed processes on the posterior margin of the abdominal tergum V, and S-shaped aedeagus. The female adult has a long and tongue-shaped subgenital plate on the abdominal sternum VIII, which extends to the posterior margin of the abdominal sternum IX. A male key to the Vietnamese species of Togoperla is provided. The finding of this new species provides evidence of an extension of the geographical distribution of Togoperla to tropical mainland Southeast Asia.

Chinoperla rhododendrona, a New Species of Perlidae (Insecta: Plecoptera) from Vietnam

Abstract A new perlid stonefly, Chinoperla rhododendrona n. sp., is described from a tropical mountain stream in central Vietnam. The male adult of this species can be characterized by the strongly setous body and unique L‐shaped genital structure. The female adult can be distinguished by the posteromedially sclerotized and widely notched subgenital plate. The egg is unique among its congeners as it has smooth chorion and long and narrow collar. Illustrations of diagnostic characters are provided.

Agnetina den, a new species of perlid stonefly (Plecoptera: Perlidae) from Vietnam

A new species of perlid stonefly, Agnetina den, is described from Vietnam. Male adults of this species can be easily distinguished by their black body color pattern, submedian patches of sensilla basiconica on hemitergites 7–8, and clusters of long dense fine setae on the inner sides the abdominal tergites. Illustrations of habitat and diagnostic characters are presented.

Vietnamese Stonefly Species of the Genus Tyloperla (Plecoptera: Perlidae)

Abstract Vietnamese stonefly species of the genus Tyloperla Sivec and Stark are reviewed. As a result, two new species, Tyloperla catcat sp. nov. and T. trui sp. nov., are described. Descriptions, diagnoses, distributions, material data, taxonomic remarks, and a male key to the Vietnamese species are provided.