Vietnamellidae (Insecta, Ephemeroptera) of Thailand.

The genus Vietnamella Tshernova, 1972 is investigated in detail for the first time in Thailand. As a consequence, four species are recognized, namely Vietnamella maculosasp. nov., Vietnamella thani Tshernova, 1972, Vietnamella sp. B and Vietnamella sp. C. Herein, larvae and eggs of V. maculosasp. nov. are described and reported from Chiang Rai Province. The larva of Vietnamella sp. B from Tak Province is also described, but not named due to insufficient material, and the imaginal stages and eggs of V. thani Tshernova, 1972 are described and presented for the first time. Our morphological evidence is supported with COI data. The phylogeny showed that four different lineages of the genus Vietnamella occur in Thailand, one of them, viz., Vietnamella sp. C, only known from a couple of COI sequences retrieved from the Barcode of Life Data System (BOLD). Diagnoses for all known Oriental species are also presented

Review and integrative taxonomy of the genus Prosopistoma Latreille, 1833 (Ephemeroptera, Prosopistomatidae) in Thailand, with description of a new species.

Three species of the genus Prosopistoma Latreille, 1833 (Prosopistomatidae) are currently reported from Thailand. A new species, Prosopistomacarinatumsp. n., is described here based on specimens from western and southern Thailand. The new species can be easily distinguished from the other members of Prosopistoma by the following combination of characteristics: (i) the presence of two ridged longitudinal lines on each side of its carapace, (ii) antenna 7-segmented, (iii) a strongly convex carapace and (iv) nine pectinate setae on the ventral margin of the fore tibiae. A comparison between the key characteristics of P.carinatumsp. n. and the known Thai species is provided. Results of analysis of the mitochondrial cytochrome oxidase I (COI) gene (658 bp) of three species, as well as the distribution of the Thai species, are also discussed

Challenges Using Extrapolated Family-level Macroinvertebrate Metrics in Moderately Disturbed Tropical Streams: a Case-study From Belize

Family-level biotic metrics were originally designed to rapidly assess gross organic pollution effects, but came to be regarded as general measures of stream degradation. Improvements in water quality in developed countries have reignited debate about the limitations of family-level taxonomy to detect subtle change, and is resulting in a shift back towards generic and species-level analysis to assess smaller effects. Although the scale of pollution characterizing past condition of streams in developed countries persists in many developing regions, some areas are still considered to be only moderately disturbed. We sampled streams in Belize to investigate the ability of family-level macroinvertebrate metrics to detect change in stream catchments where less than 30% of forest had been cleared. Where disturbance did not co-vary with natural gradients of change, and in areas characterized by low intensity activities, none of the metrics tested detected significant change, despite evidence of environmental impacts. We highlight the need for further research to clarify the response of metrics to disturbance over a broader study area that allows replication for confounding sources of natural variation. We also recommend research to develop more detailed understanding of the taxonomy and ecology of Neotropical macroinvertebrates to improve the robustness of metric use

A New Species of Vietnamella Tshernova 1972 (Ephemeroptera: Vietnamellidae) from Thailand.

The larva, male subimago, female imago, and eggs of V. nanensis sp. n. are described based on specimens from Mae Hong Son and Nan provinces, Thailand. The female subimago is described based on a photograph of a specimen reared to the imago stage. The species previously was distinguished only by DNA barcode data and designated as Vietnamella sp. C. Based on morphology, the larva of the new species can be distinguished with the following combination of characteristics: (i) pattern of serration on the ventral margin of the forefemur, (ii) posterolateral margins of abdominal terga with pairs of acute tubercles, especially terga VI and VII, (iii) a well-developed pair of median ridge projections on tergum X, (iv) the second segment of the maxillary palp being about 1.3× the length of the third segment, and (v) females containing eggs with prominent protuberances on the chorionic surface. A key to larvae of all known species in the genus is provided

Sangpradubina, an astonishing new mayfly genus from Thailand (Ephemeroptera: Leptophlebiidae: Atalophlebiinae).

A newly discovered representative of Leptophlebiidae is described and illustrated from Thailand as Sangpradubina thailandica, gen. nov. and sp. nov., based on larvae and reared adults. This new species presents an interesting transitional position, being close to Choroterpes s.l. in the winged stages, but closer to Thraulus s.l. in the nymphal stage.   Nymphs are differentiated from those of all genera of the Thraulus lineage by the combination of gill I consisting of only a single and slender lamella, gills II-VII being fimbriate only in the distal half, each mandible having a tuft of setae only in the middle of the lateral margin, each maxilla having a well-developed anterolateral projection, fore- and middle femora each having a row of long setae on the outer margin, as well as tarsal claws having 4 denticles at the base and 9 in the apical position. Adults of the new genus barely differ from any genera of the Choroterpes lineage. The egg chorionic structure of Sangpradubina also appears to be unusual in that KCT's are concentrated on one pole

First record of Paegniodes Eaton, 1881 (Ephemeroptera, Heptageniidae) from Thailand with description of a new species.

A new species of Heptageniidae, Paegniodes sapanensissp. nov., is described based on larvae, subimagos, eggs, and COI data. The mayfly genus Paegniodes Eaton, 1881 is reported for the first time from Thailand. The larva of the new species can be distinguished from other known Paegniodes species by i) lamellae of gill I ca 1/4 of fibrilliform portion and ii) mandibles and basal segment of maxillary palp without dense setae on margin. The subimago characters useful to distinguish this new species from previously known species are i) the median stripes on abdominal terga and ii) shape of the female subgenital and subanal plates. The genetic distance between the new species and P. cupulatus (Eaton, 1871) was approximately 11%. The morphological characters of the new species are discussed and compared to other known species

A new species of Platybaetis Müller-Liebenau, 1980 (Ephemeroptera: Baetidae) from Thailand, with description of the imago of Platybaetis bishopi Müller-Liebenau, 1980

Platybaetis bishopi Muller-Liebenau, 1980 was originally described from Malaysia only at the larval stage. We provide the first description of the imaginal stage of P. bishopi based on materials from Thailand. The imago of this species can be separated from the known species by coloration of abdominal terga and coloration of wings. A new species, Platybaetis nayokensis sp. nov., is described based on male and female imagos and larvae from Thailand. The larva of this species is mainly distinguished by medium acute spines on the posterior margin of the abdominal terga and two apical setae on the glossa, which seem to be shorter than in other species. The imago can be separated by the abdominal color pattern. The larva of this genus is adapted to live on wet rocks projecting out of water; it prefers large stones near small waterfalls or areas between two large rocks in running water