Labiobaetis Novikova & Kluge in Borneo (Ephemeroptera, Baetidae)

Redescription of Papuanatula Lugo-Ortiz & McCafferty (Ephemeroptera, Baetidae), with description of a new subgenus and 20 new species

Material from the type localities of most described species of Papuanatula and rich material newly collected across New Guinea and on the island Sulawesi form the bases for this comprehensive study of the genus, including the description of a new subgenus Papuafiliolasubgen. nov. and 20 new species. Species delimitation is based on morphology of larvae and partly also imagos, supported by mitochondrial DNA data (COI) for some of the species. The total number of species is augmented from six to 26. The genus has a disjunct distribution on the islands New Guinea (incl. New Britain) and Sulawesi. A key to the larvae of all species is provided. Morphological similarities, the relationship of Papuanatula to other genera of Baetidae, and possible explanations for the high diversity in New Guinea are discussed.

First contribution to the genera Branchiobaetis and Megabranchiella (Ephemeroptera, Baetidae) in China, with descriptions of two new species

Branchiobaetis Kaltenbach, Kluge & Gattolliat, 2022 and Megabranchiella Phlai-ngam & Tungpairojwong, 2022 (Ephemeroptera: Baetidae) are newly recorded in China. Two new species, Branchiobaetisborealis sp. nov. based on larval stage and Branchiobaetismegasinus sp. nov. based on larval and imaginal stages associated by laboratory rearing, are described. Megabranchiellalongusa Phlai-ngam & Tungpairojwong, 2022, previously only distributed from Thailand, is recorded from China for the first time.

Taxonomic review of the Oriental genus Polyplocia Lestage, 1921 (Ephemeroptera, Euthyplociidae), with two new records for Thailand

Previously, the euthyplociid mayfly from Thailand was reported as Polyplocia spp. without designation to any nominal species. In this study, the genus Polyplocia Lestage, 1921 in Thailand was reviewed. Two species are recognized: Polyplociaorientalis Nguyen & Bae, 2003 and P.nebulosa Gonçalves & Peters, 2016. This is the first report of P.nebulosa in Continental Asia. Cytochrome c oxidase subunit I (COI) data and illustrations based on nymphal characters were used to confirm two different species in Thailand. Additional morphological characteristics of the nymph and eggs of the two species from Thailand are also shown in detail. The taxonomic status of Polyplocia in the Oriental region is reviewed. Keys to known nymphal and imaginal stages are provided and the distribution of Polyplocia in the Oriental region is discussed.

New species of Nigrobaetis from Southeast Asia (Ephemeroptera, Baetidae)

Based on larvae collected in the Philippines, Borneo (Kalimantan), Sumba, and Sumatra, the presence of the genus Nigrobaetis in the Philippines and Indonesia is reported for the first time. Six new species are described and illustrated, two from the Philippines and four from Indonesia. A larval key to all Nigrobaetis species of the Philippines, Indonesia and neighbouring continental Southeast Asia is provided, morphological differences to the species of Taiwan are discussed as well. The eggs of three new species are described, and the morphology of the eggs of Nigrobaetis is briefly discussed.

First report of the Afrotropical genus Securiops Jacobus, McCafferty & Gattolliat (Ephemeroptera, Baetidae) from Southeast Asia, with description of a new species

Recent collections in Thailand revealed the occurrence of the genus Securiops in Asia, formerly known from the Afrotropical Realm only. A new species of Securiops is described and illustrated based on larvae and eggs. Eggs of this genus are described for the first time. Morphological differences between the new species and the species from Africa are discussed. The number of species in the genus Securiops is augmented to five.

A widespread new genus of Baetidae (Baetidae, Ephemeroptera) from Southeast Asia

A reinvestigation of type and other material of Baetisjavanicus Ulmer, 1913 and Baetissabahensis Müller-Liebenau, 1984, together with new material from Southeast Asia revealed a new genus, Branchiobaetis gen. nov. The above species are formally assigned to the new genus Branchiobaetis gen. nov. It is characterized by the presence of accessory gills ventrally near fore coxa and at the base of maxillae, a peculiar folding of the gonostyli developing under the cuticle of last instar male larvae, together with a unique combination of other larval characters. Besides the two formerly described species, five new species are identified using a combination of morphology and molecular characters (COI, Kimura 2-parameter distances), four species from Sumatra and one from the Philippines. They are described and illustrated at the larval stage. Additionally, a complementary description of larva and adult stages of the generic type species B.javanicus comb. nov. as well as the first description of the eggs are provided. Furthermore, new reports of B.javanicus comb. nov. and B.sabahensis comb. nov. are indicated. The distribution of Branchiobaetis gen. nov. includes the Indonesian Sunda Islands, Borneo, and the Philippines. A key to the larval stage of all species is provided.

Two new species of Centroptilum Eaton, 1869 from North Africa (Ephemeroptera, Baetidae)

Based on recently collected larvae from Algeria and Morocco, the species delimitation within the genus Centroptilum Eaton, 1869 in that region is validated. Two new species are described and illustrated, one from north-eastern Algeria, and one from North Morocco, using an integrated approach with morphological and molecular evidence. A table summarising the morphological differences between the new species and Centroptilumluteolum (Müller, 1776) from Central Europe is provided. Further, molecular evidence for additional undescribed species of Centroptilum in other regions of the West Palearctic is provided and discussed.

First contribution to Labiobaetis Novikova & Kluge in Cambodia (Ephemeroptera, Baetidae), with description of two new species

Material collected in 2018 in Cambodia gives us first insights into the diversity of Labiobaetis Novikova & Kluge, 1987 in this country. No species has been reported so far. We identified two new species using a combination of morphology and genetic distance (COI, Kimura 2-parameter). They are described and illustrated based on their larvae. A key to all Labiobaetis species of continental Southeast Asia is provided. The interspecific K2P distance between the two new species is 20-21%, the intraspecific distance of one of them is 1%. The total number of Labiobaetis species worldwide is augmented to 156.

New species of Labiobaetis Novikova & Kluge from Southeast Asia and New Guinea (Ephemeroptera, Baetidae)

Material collected between 2006 and 2016 in Borneo, Sulawesi, and New Guinea further increased our knowledge of Labiobaetis Novikova & Kluge in these regions. Five species were previously reported from Borneo, two from Sulawesi, and 33 from New Guinea. Six new species have been identified using a combination of morphology and genetic distance (COI, Kimura 2-parameter), one species from Borneo (Brunei), one from Sulawesi, and four from New Guinea. They are described and illustrated based on their larvae and keys to the species of the relevant groups are provided. Additionally, new reports, a complementary description, and the COI sequence for L.dendrisetis Kaltenbach & Gattolliat are presented. The distribution of Labiobaetis in the Wallacea region is discussed based on the new findings. The total number of Labiobaetis species worldwide is augmented to 153.

The success story of Labiobaetis Novikova & Kluge in the Philippines (Ephemeroptera, Baetidae), with description of 18 new species

Material collected between 1994 and 2020 in the Philippines, covering most main islands like Luzon, Mindoro, Palawan, Negros, Cebu, Leyte, and Mindanao and some smaller islands, substantially increased our knowledge of Labiobaetis Novikova & Kluge in this archipelago. Only three species were previously reported: L.molawinensis (Müller-Liebenau, 1982) and L.sumigarensis (Müller-Liebenau, 1982) from larvae and L.boettgeri (Ulmer, 1924) from adults. Eighteen new species have been identified using a combination of morphology and genetic distance (COI, Kimura 2-parameter). They are described and illustrated based on their larvae and a key to all species in the Philippines is provided. The total number of Labiobaetis in the Philippines has increased to 21 species. Additional diversity of Labiobaetis based on molecular evidence only is presented as Molecular Operational Taxonomic Units (MOTUs) without description. The interspecific K2P distances in the Philippines are between 15% and 27%, the intraspecific distances are usually between 0% and 3%. The total number of Labiobaetis species worldwide is augmented to 144.

Cymbalcloeon gen. nov., an incredible new mayfly genus (Ephemeroptera: Baetidae) from Thailand

The genus Cymbalcloeon gen. nov. (Ephemeroptera: Baetidae) is established for a new species Cymbalcloeon sartorii sp. nov. from Thailand, based on larval stage. This genus is unique among all of the Baetidae by the presence of three pairs of single gills on segments V-VII, ventrally oriented to cover the sterna VI-IX. Cymbalcloeon sartorii gen. nov. et sp. nov. presents unique or rare morphological characters such as a deeply concave margin between the prostheca and mola, without setae; a very large subtriangular process of the left mandible; a maxillary palp segment II with scarce and very long setae; almost completely fused labial palp segments II and III with numerous very long setae; elongate tarsal claw with two rows of teeth; a shagreen surface of the terga and paraproct; and a very reduced body size. The gills of the new genus move very quickly during respiration and present a near-synchronous protraction. Due to the very derived larval morphological character and the unknown imaginal stage, the exact phylogenetic position of the genus remains unclear; it most certainly belongs to the concept of Anteropatellata and is possibly closely related to the genus Baetopus.

Reports of Baetidae (Ephemeroptera) species from Tafna Basin, Algeria and biogeographic affinities revealed by DNA barcoding

Background

The Mediterranean basin is known to be the cradle of many endemic species. Within mayflies (Insecta, Ephemeroptera), North African species belonging to the family Baetidae remain poorly known and, traditionally, affinities to European fauna were proposed. Recent studies, based on molecular reconstructions, showed closer relationships to Mediterranean islands fauna.

New information

Baetidae were sampled from North-West Algerian wadis (Tafna basin) and involved in COI barcoding reconstructions. Seven species were identified. The subgenus Rhodobaetis is represented by Baetisatlanticus known previously from Macaronesian islands, Europe and Morocco and the Maghrebian endemic Baetissinespinosus. Specimens, previously identified as Cloeoncf.dipterum, correspond to Cloeonperegrinator and, until now, only reported from Macaronesia. Besides the confirmation of endemicity of some species, such as Procloenstagnicola and B.sinespinosus, our molecular study showed quite original results for relationships between European, insular and Algerian species. Baetismaurus stood out as a North African endemic sister clade to an Iberian clade. Furthermore, we found clear interspecific distances between Algerian and European clades for A.cf.sinaica and B.cf.pavidus, suggesting the presence of cryptic species in Algeria. However, additional studies are needed, as, for the moment, no clear morphological characters were found to separate the different clades and support them as valid species.