Redescriptions of Indian species of Nigrobaetis Kazlauskas (in Novikova & Kluge) 1987 (Ephemeroptera, Baetidae).

The European species Nigrobaetis gracilis (Bogoescu & Tabacaru 1957) and more than 19 Asian and African species of Nigrobaetis Kazlauskas (in Novikova & Kluge) 1987 belong to the subgenus Margobaetis Kang & Yang 1994, which is characterized by peculiar asymmetric eggs and narrow paraglossa of larval labium. A new synonymy is established: Nigrobaetis (Margobaetis) minutus (Mller-Liebenau 1984) = N. paramakalyani Kubendran & Balasubramanian in Kubendran et al. 2015 = N. sumbensis Kaltenbach & Gattolliat 2023, synn.n.; winged stages (male and female imagines and subimagines) and eggs of this species are described for the first time. N. (M.) minutus is widely distributed on Oriental Region, being revealed in West Malaysia, Southern India, Sumba and Sulawesi islands in Indonesia. Winged stages (male and female imagines and subimagines) and eggs of Nigrobaetis (Margobaetis) klugei Sivaruban et al. 2022 are described for the first time.

Tightening the requirements for species diagnoses would help integrate DNA-based descriptions in taxonomic practice.

Modern advances in DNA sequencing hold the promise of facilitating descriptions of new organisms at ever finer precision but have come with challenges as the major Codes of bionomenclature contain poorly defined requirements for species and subspecies diagnoses (henceforth, species diagnoses), which is particularly problematic for DNA-based taxonomy. We, the commissioners of the International Commission on Zoological Nomenclature, advocate a tightening of the definition of "species diagnosis" in future editions of Codes of bionomenclature, for example, through the introduction of requirements for specific information on the character states of differentiating traits in comparison with similar species. Such new provisions would enhance taxonomic standards and ensure that all diagnoses, including DNA-based ones, contain adequate taxonomic context. Our recommendations are intended to spur discussion among biologists, as broad community consensus is critical ahead of the implementation of new editions of the International Code of Zoological Nomenclature and other Codes of bionomenclature.

Redescription of the subgenus Rhithrogeniella Ulmer 1939 (Ephemeroptera, Heptageniidae, genus Ecdyonurus) based on reared specimens from India and Thailand.

Rhithrogeniella Ulmer 1939 is treated here as a subgenus of the genus Ecdyonurus Eaton 1868 (s. l.). The subgeneric name Rhithrogeniella is a senior synonym of Afghanurus Demoulin 1964 syn. n., Paracinygmula Bajkova 1975 syn. n. and Nixe Flowers 1980 syn. n. Additional description of Ecdyonurus (Rhithrogeniella) ornatus (Ulmer 1939) is given based on imagines and subimagines of both sexes reared from larvae in India and Thailand; lectotype of this species name is designated. Synonymy of E. (Rh.) ornatus and E. (Rh.) tonkinensis Soldán & Braasch 1986 is established (syn. n.). Male and female imagines and subimagines of an unnamed species of Rhithrogeniella are reported from India.

Contribution to the knowledge of the subgenus Tenuibaetis Kang & Yang 1994 (Ephemeroptera, Baetidae, Baetis s. l.).

The taxon Tenuibaetis Kang & Yang (in Kang, Chang & Yang) 1994 is accepted here as a subgenus of the genus Baetis Leach 1815, but not as a genus. In connection with this, new combinations are established: Baetis (Tenuibaetis) parvipterus (Fujitani et al. 2011) comb. n., Baetis (Tenuibaetis) fujitanii (Kaltenbach & Gattolliat 2019) comb. n., Baetis (Tenuibaetis) himani (Kubendran et al. in Kubendran et al. 2022) comb. n., Baetis (Tenuibaetis) kangi (Kubendran et al. in Kubendran et al. 2022) comb. n. and Baetis (Tenuibaetis) panhai (Suttinun et al. 2022) comb. n. Based on reared material, imagines of both sexes and larvae of Baetis (Tenuibaetis) ursinus Kazlauskas 1963, Baetis (Tenuibaetis) hissaricus Novikova 1991, Baetis (Tenuibaetis) frequentus Müller-Liebenau & Hubbard 1985 (= Indobaetis michaelohubbardi Selva-kumar et al. 2012, syn. n.) and B. (T.) fujitanii are redescribed. B. (T.) panhai is redescribed based on subimago reared from larva. Two new species from Southern India, Baetis (Tenuibaetis) kaltenbachi sp. n. and Baetis (Tenuibaetis) bialatus sp. n. are described based on imagines reared from larvae. A new species from Thailand, Baetis (Tenuibaetis) octomaculatus sp. n. is described based on imagines reared from larvae.

Indian species of Teloganodes Eaton 1882 (including subgenera Dudgeodes Sartori 2008 and Derlethina Sartori 2008) (Ephemeroptera, Teloganodidae).

According to the classification proposed in the previous publication by Kluge, the genus Teloganodes Eaton 1882 is divided into three subgenera distinguished only by tergalii number: the subgenus Teloganodes (with 5 pairs of tergalii on uromeres II-VI), the subgenus Dudgeodes Sartori in Sartori et al. 2008 (with 4 pairs of tergalii on uromeres II-V) and the subgenus Derlethina Sartori in Sartori et al. 2008 (with 3 pairs of tergalii on uromeres II-IV). All three subgenera are represented in Southern India. Based on the new material, additional descriptions are given to the following species: T. (Teloganodes) kodai Sartori in Sartori et al. 2008 (= Teloganodes barathyae Sivaruban et al. in Martynov et al. 2022, syn. n.); Teloganodes (Teloganodes) dentatus Navás 1932 (= T. sartorii Selvakumar et al. in Selvakumar et al. 2014, syn. n.); Teloganodes (Dudgeodes) palnius (Selvakumar et al. in Selvakumar et al. 2014) (= Dudgeodes bharathidasani Anbalagan et al. 2015, syn. n.; = Dudgeodes sartorii Srinivasan et al. 2021, syn. n.; = Dudgeodes molinerii Sivaruban et al. in Martynov et al. 2022, syn. n.); Teloganodes (Derlethina) tamiraparaniae (Selvakumar et al. in Selvakumar et al. 2014). A new species T. (Teloganodes) velutinus sp. n. is described from the Western Ghats based on larvae, female imagines reared from larvae and eggs.

Reclassification of Teloganodes Eaton 1882 (including subgenera Dudgeodes Sartori 2008 and Derlethina Sartori 2008) with a new species from Sulawesi (Ephemeroptera, Teloganodidae).

The genera Teloganodes Eaton 1882 sensu Sartori et al. 2008 and Dudgeodes Sartori 2008 in the original sense, were artificial taxa, and the genus Derlethina Sartori 2008 differed from them only by greater reduction of posterior tergalii. In the present paper, the genus Teloganodes is accepted in wide sense and includes the 3 following formal subgenera: (1) subgenus Teloganodes, stat. n. (= Macafertiella Wang in Wang & McCafferty 1996) contains only species with 5 pairs of tergalii (i.e. tergalii II-VI); (2) subgenus Dudgeodes Sartori in Sartori et al. 2008, stat. n. contains all species with 4 pairs of tergalii (i.e. tergalii II-V); (3) subgenus Derlethina Sartori in Sartori et al. 2008, stat. n. contains species with 3 pairs of tergalii (i.e. tergalii II-IV). The species Teloganodes jacobusi Sartori in Sartori et al. 2008 and T. hubbardi Sartori in Sartori et al. 2008 are moved to the subgenus Dudgeodes. The following new combinations are established: Teloganodes (Dudgeodes) hutanis (Sartori in Sartori et al. 2008) comb. n.; T. (D.) stephani (Sartori in Sartori et al. 2008) comb. n.; T. (D.) ulmeri (Sartori in Sartori et al. 2008) comb. n.; T. (D.) pescadori (Sartori in Sartori et al. 2008) comb. n.; T. (D.) celebensis (Sartori in Sartori et al. 2008) comb. n.; T. (D.) palnius (Selvakumar et al. in Selvakumar et al. 2014) comb. n.; T. (D.) bharathidasani (Anbalagan in Anbalagan et al. 2015) comb. n.; T. (D.) romani (Martynov et al. 2016) comb. n.; T. (D.) bauernfeindi (Garces & Sartori in Garces et al. 2020) comb. n.; T. (D.) freitagi (Garces & Sartori in Garces et al. 2020) comb. n.; T. (D.) luntian (Garces & Sartori in Garces et al. 2020) comb. n.; T. (D.) pangantihoni (Garces & Sartori in Garces et al. 2020) comb. n.; T. (D.) tabang (Garces & Sartori in Garces et al. 2020) comb. n.; T. (D.) vonrinteleni (Garces & Sartori in Garces et al. 2020) comb. n.; T. (D.) sartorii (Srinivasan et al. 2021) comb. n.; T. (D.) molinerii (Sivaruban et al. in Martynov et al. 2022) comb. n.; T. (D.) selvakumari (Martynov & Palatov in Martynov et al. 2022) comb. n.; T. (Derlethina) eloisae (Sartori in Sartori et al. 2008) comb. n.; T. (Derlethina) tamiraparaniae (Selvakumar et al. in Selvakumar et al. 2014) comb. n. Larvae, subimagines, imagines of both sexes and eggs of T. (D.) celebensis are described; a new species, T. (D.) rasus sp. n. is described from Sulawesi based on male imago and subimago reared from larva.

Diagnosis, variability, distribution and systematic position of Labiobaetis pulchellus (Müller-Liebenau & Hubbard 1985) (Ephemeroptera, Baetidae, Baetis s. l.).

A new synonymy to Labiobaetis pulchellus (Müller-Liebenau & Hubbard, 1985) (= L. soldani Kubendran et al. 2014, syn. n.) is established based on examination of imagines reared from larvae in India and Sri Lanka. This species belongs to the tricolor group, which comprises Holarctic species L. tricolor (Tshernova, 1928), L. propinquus (Walsh, 1863), L. calcaratus (Keffermüller, 1972), and some Oriental species.

A new, widespread genus of Baetidae from South Asia (Insecta, Ephemeroptera).

Material collected on different islands across South Asia revealed a new genus of Baetidae with a widespread distribution, Arcobaetisgen. nov. The larvae present important similarities with Nigrobaetis, but have paraglossae dorsally with an arc of long, spine-like setae in distal area; long, slightly feathered setae between prostheca and mola of both mandibles; and very slender legs with row of short setae at dorsal margin of femur. The male imago has an extraordinarily small 3rd (apical) segment of gonostylus, which is much narrower than the apex of the 2nd segment. The new genus includes five species: A.sumbawensissp. nov. is described from Sumbawa (Indonesia) based on larvae, A.sumatrensissp. nov. from Sumatra (Indonesia) based on larvae, A.bornensissp. nov. from Borneo (Brunei) based on larvae, and A.sripadaisp. nov. (type species) is described from Sri Lanka based on a reared male imago with its larval and subimaginal exuviae; A.gracilentus (Chang & Yang, 1994), comb. nov. from Taiwan, formerly described in Margobaetis Kang & Yang, 1994, a subgenus of Baetis Leach, 1815, and subsequently transferred to the genus Nigrobaetis Kazlauskas (in Novikova & Kluge), 1987, is transferred to the new genus. A key to the larvae of all species is provided. Morphological similarities and the relationship of the new genus to other genera of Baetidae are discussed.

Redescription of the subgenus Securiops Jacobus, McCafferty & Gattolliat 2006 (Ephemeroptera, Baetidae, Procloeon Bengtsson 1915).

The taxon Securiops Jacobus, McCafferty& Gattolliat 2006 is treated here as a subgenus of the genus Procloeon Bengtsson 1915; it shares all characters of Procloeon s.l. and besides them, has peculiar autapomorphies in mouthparts structure. Diagnoses of Cloeon/fg1 (or the tribe Cloeonini sensu Kluge 2016), Procloeon/g1 (or the genus Procloeon sensu Kluge 2016) and Securiops are given. Larvae of the South African species Procloeon (Securiops) falcatum (Crass 1947) comb. n. are described for the first time. Based on reared specimens from Zambia, larvae of Procloeon (Securiops) macafertiorum Lugo-Ortiz (in Lugo-Ortiz & McCafferty) 1996 are redescribed; subimagines, imagines and eggs of this species are described for the first time. New larval characters of Procloeon (Securiops) mutadens (Jacobus et al. 2006) comb. n. are reported based on a larva from Gambia. Based on reared specimens from Thailand, larvae of Procloeon (Securiops) primasia (Kaltenbach et al. 2023) comb. n. are redescribed; subimagines, imagines and well-developed eggs of this species are described for the first time. Genitalia of Cheleocloeon excisum (Barnard 1932) are figured for the first time.

Taxonomic significance of microlepides on subimaginal tarsi of Ephemeroptera.

In each mayfly individual, the surface of the subimaginal cuticle significantly differs both from imaginal and larval cuticles, being different on different parts of the body. Most of the subimaginal body, including femora and tibiae, is covered with microtrichia. Tarsal segments are either also covered with microtrichia, or their microtrichia are transformed into microlepides of various shapes. The most usual forms of microlepides are the pointed and the blunt ones. Arrangements of microtrichia, pointed microlepides, blunt microlepides and other forms of microlepides on certain tarsomeres represent good taxonomic characters, which in some cases allow characterization of high level taxa, and in some cases distinguish closely related species. Arrangement of microlepides and microtrichia on subimaginal tarsi of examined mayfly species is given. The following new synonyms are proposed: Afroptilum boettgeri (Kopelke 1980) = Xyrodromeus africanus Lugo-Ortiz McCafferty 1997, syn. n.; Labiobaetis vinosus (Barnard 1932) = L. tenuicrinitus (Kopelke 1980), syn. n.; Baetis parvulus Crass 1947 = Baetis permultus Kopelke 1980, syn. n.; Epeorus gilliesi Braasch 1981 = Epeorus petersi Sivaruban et al. 2013, syn. n.; Dicercomyzon femorale Demoulin 1954 = Dicercomyzon costale Kimmins 1957, syn. n.

Two new species of Waynokiops Hill et al. 2010 (Ephemeroptera: Baetidae) from the Oriental Region.

A new species found in northern Thailand and northern India, Waynokiops pentacanthus sp. n., is described based on eggs, larvae, subimagines and imagines of both sexes associated by rearing. A new species from southern India, Waynokiops palifer sp. n. is described based on a mature larva with female subimago and eggs extracted from this larva. All larvae of both species were collected in rivers running in mountain areas. Formerly, the genus Waynokiops Hill et al. 2010 included a single species W. dentatogriphus Hill et al. 2010 known from a few larvae collected in lakes of North America and unknown before 2007. Based on the fact that two newly discovered species of Waynokiops have an Oriental distribution, an assumption is expressed, that W. dentatogriphus is also originally distributed somewhere in the Oriental Region, from where it was introduced into North America. Winged stages are described for Waynokiops for the first time, allowing a more complete generic diagnosis and a better understanding of its systematic position.

Review of the subgenus Euthraulus (Ephemeroptera, Leptophlebiidae, genus Choroterpes) from the Western Ghats (India).

The subgeneric name Monochoroterpes Kluge Jacobus 2015 is regarded here to be a junior synonym of Euthraulus Barnard 1932 (syn. n.), based on a wider understanding of more species from each group. Based on male and female imagines reared from larvae, the following species are described or re-described: Choroterpes (Euthraulus) alagarensis Dinakaran et al. 2009, Ch. (E.) armillatus sp. n., Ch. (E.) latus sp. n., Ch. (E.) atelobranchis sp. n., Ch. (E.) unicolor sp. n., Ch. (E.) nambiyarensis Selva-Kumar et al. 2013, Ch. (E.) angustifolius sp. n. and Ch. (E.) nandini Selvakumar Sivaramakrishnan 2015. All these species are distributed in southern India. One of them, Ch. (E.) latus sp. n., was collected in a plains river, Vaigai, in Madurai and in several localities in Sri Lanka, including a plains river, Malvatu, in Anuradhapura; formerly it was confused with another Ceylonese species, Ch. (E.) signatus (Hagen 1858). Here the characters separating Ch. (E.) signatus from Ch. (E.) latus sp. n. are reported and illustrated. Other species listed above were collected in mountain rivers in south of Western Ghats. One more species of Euthraulus is described without a formal name based a on mature male larva collected near Mumbai. The species description of Choroterpes (Euthraulus) kalladaensis Rekha et al. 2019 was based on specimens belonging both to Indialis rossi and Ch. (E.) angustifolius; since the type specimens are lost, and the description is based mainly on characters of Indialis rossi, we propose the following synonymy: Indialis rossi Peters 1975 = Choroterpes (Euthraulus) kalladaensis Rekha et al. 2019, syn. n.

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.

Review of the Kimminsula-complex (Ephemeroptera, Leptophlebiidae).

Distribution of the Kimminsula complex is limited by mountains of the Western Ghats in India and the Central Highlands in Sri Lanka. Indian taxa include the new genus Ghatula gen. n. with 2 new species, Ghatula rufa sp. n. (type species of Ghatula, described here from larvae of both sexes, female subimago, female imago and eggs associated by rearing) and Ghatula quadrimaculata sp. n. (described here from larvae of both sexes); and the genus Petersula Sivaramakrishnan 1984 with type species Petersula courtallensis Sivaramakrishnan 1984 (additionally described here from larvae of both sexes, female subimagines, female imagines and eggs associated by rearing), Petersula heptagenoides sp. n. (described here from larvae, subimagines, imagines of both sexes and eggs associated by rearing) and Petersula nathani Sivaramakrishnan & Hubbard 1984 (known as a single male imago). In Sri Lanka the Kimminsula complex is represented by the following taxa: the new genus Ceylonula gen. n. with the single species Ceylonula femoralis (Hagen 1858) comb. n. (originally in Potamanthus; redescribed here from larvae, subimagines, imagines of both sexes and eggs associated by rearing); the genus Kimminsula Peters & Edmunds 1970 with type species Kimminsula taprobanes (Walker 1853) [= Kimminsula annulata (Hagen 1858)] (redescribed here from larvae, subimagines, imagines of both sexes and eggs associated by rearing), Kimminsula fasciata (Hagen 1858) (redescribed here from larvae, subimagines, imagines of both sexes and eggs associated by rearing), Kimminsula podi sp. n. (described here from larvae, male subimagines, male imagines and eggs associated by rearing) and Kimminsula latifolia sp. n. (described here from larvae); a form intermediate between K. fasciata and K. taprobanes is described here from larvae, subimagines, imagines of both sexes and eggs associated by rearing; and the new genus Hubbardula gen. n. with the single species Hubbardula heterolepida sp. n. (described here from larvae, subimagines, imagines of both sexes and eggs associated by rearing). Systematic position of the Kimminsula-complex is discussed.

First report of Cheleocloeon Wuillot & Gillies 1993 (Ephemeroptera: Baetidae) from the Oriental Region.

A new species, Cheleocloeon vaigaiensis sp. n., is described from Southern India based on larvae, imagines and subimagines of both sexes associated by rearing. This new Oriental species is most closely related to the Afrotropical species Cheleocloeon clavifolium Kluge 2016. Formerly, the genus Cheleocloeon Wuillot & Gillies 1993 was known only from Africa, Madagascar and Arabia; this is the first report of this genus from the Oriental Region.

Review of Centroptella Braasch amp; Sold 1980 (Ephemeroptera, Baetidae).

The Eastern Hemisphere genus Centroptella Braasch Sold 1980 (s. l.) is divided into three subgenera, the subgenus Centroptella s. str., the subgenus Crassolus Salles et al. 2016 and the subgenus Chopralla Waltz McCafferty 1987. Among them, Centroptella s. str. and Crassolus are more closely related one to another than to Chopralla, that in the hierarchical nomenclature can be expressed as the following: Centroptella/g1 {Chopralla + Centroptella/g2 {Crassolus + Centroptella/g3}}. The subgenus Centroptella s. str. is distributed in the Oriental Region and Australia; it includes the following species: Centroptella (s. str.) longisetosa Braasch Sold 1980 with a new subspecies C. longisetosa cinerea subsp. n. (described here from southern India based on larvae, subimagines, imagines of both sexes and eggs associated by rearing); C. (s. str.) femorata sp. n. (described here from Lombok Island based on larva, subimago and male imago associated by rearing); C. (s. str.) soldani Mller-Liebenau 1983 (known from Sri Lanka and redescribed here based on larvae, female subimagines and eggs associated by rearing); C. (s. str.) ornatipes sp. n. (described here from southern India based on larvae, subimagines, imagines of both sexes and eggs associated by rearing); C. (s. str.) breviseta sp. n. (described here from New Guinea based on larvae, subimagines, female imagines and eggs associated by rearing); C. (s. str.) illiesi (Lugo-Ortiz McCafferty 1998) (known from Australia and redescribed here based on non-reared larvae, subimagines and imagines); C. (s. str.) fustipalpus (Lugo-Ortiz McCafferty 1998) (known from Australia as larvae only); C. (s. str.) quadrata Shi Tong 2019 (known from China as larvae only); C. (s. str.) sp. cf. quadrata (reported here from Borneo based on male and female larvae ready to molt to subimago); C. (s. str.) ovata Shi Tong 2019 (known from China as larvae only); and C. (s. str.?) papilionodes Marle et al. 2016 (known from Borneo as larvae only). The subgenus Crassolus is distributed in the Afrotropical Region, Oriental Region and southern Palaearctic Region; it includes the following species: Centroptella (Crassolus) inzingae (Crass 1947) (known from South Africa as larvae and imagines); C. (Crassolus) saxophila (Agnew 1961) (known from South Africa and redescribed here based on larvae, subimagines, imagines of both sexes and eggs associated by rearing); C. (Crassolus) ludmilae sp. n. (described here from Tanzania based on larvae, subimagines, imagines of both sexes and eggs associated by rearing), C. (Crassolus) ingridae Kluge et al. 2020 (known from Indochina and here redescribed based on larvae, subimagines, imagines of both sexes and eggs associated by rearing), C. (Crassolus) pontica (Sroka et al. 2019) (known from Turkey as larvae only); C. (Crassolus?) bifida (Shi Tong 2019) (known from China as larvae only); C. (Crassolus?) sp. Nepal (reported here from Nepal based on larva. The subgenus Chopralla is distributed in the Oriental Region; it includes the following species: Centroptella (Chopralla) ceylonensis Mller-Liebenau 1983 (= C. similis Mller-Liebenau 1983 syn. n.) (known from southern India and Sri Lanka and redescribed here based on larvae, subimagines, imagines of both sexes and eggs associated by rearing); C. (Chopralla) ghatensis sp. n. (described here from southern India based on larvae, subimagines, imagines of both sexes and eggs associated by rearing); C. (Chopralla) rufostriata sp. n. (described here from Lombok Island based on larvae, subimagines, imagines of both sexes and eggs associated by rearing); C. (Chopralla) papuanica sp. n. (described here from New Guinea based on larvae, subimagines, female imagines and eggs associated by rearing); C. (Chopralla) pusilla Mller-Liebenau 1984 (known from Borneo and redescribed here based on male larvae ready to molt to subimago); C. (Chopralla) kangi sp. n. (described here from Borneo based on male and female larvae ready to molt to subimago); C. (Chopralla) colorata Sold et al. 1987 [= C. fusina (Tong Dudgeon 2003) syn. n.] (known from Vietnam and China as larvae and imagines associated by rearing); and C. (Chopralla) bintang Marle et al. 2016 (known from Borneo as larvae only).

Review of the Oriental genus Indocloeon Müller-Liebenau 1982 (Ephemeroptera: Baetidae) with descriptions of two new species.

The genus Indocloeon Müller-Liebenau 1982 (s. l.) is divided into two subgenera, the subgenus Indocloeon (s. str.) and the subgenus Hindocloeon subgen. n. which differ one from another by certain characters of larvae, winged stages and eggs. The subgenus Indocloeon is distributed in Sri Lanka only and includes two species, Indocloeon (Indocloeon) primum Müller-Liebenau 1982, and Indocloeon (Indocloeon) secundum sp. n., which are described here based on larvae, subimagines, imagines of both sexes and eggs associated by rearing. The subgenus Hindocloeon (type species Indocloeon indonesiae Kluge 2012) is widely distributed in the Oriental region. A new species Indocloeon (Hindocloeon) continentale sp. n. is described from Thailand based on larvae, subimagines, imagines of both sexes and eggs associated by rearing; subimagines presumably placed in this species, are reported from southern India. Some characters of Indocloeon (Hindocloeon) indonesiae Kluge 2012 are illustrated for the first time. The species originally described as Cloeon longistylus Demoulin 1969 is placed in Indocloeon as Indocloeon (Hindocloeon) longistylus comb. n. Subimagines of two unnamed species of Hindocloeon are reported from Vietnam and Java. Keys to known larvae and imagines are given.

Review of Oculogaster Kluge 2016 (Ephemeroptera, Baetidae, Procloeon Bengtsson 1915).

The subgenus Oculogaster Kluge 2016 is divided into two species groups: the «African group¼ includes Procloeon (Oculogaster) cylindroculum Kimmins 1956, P. (O.) barnardi sp. n., P. (O.) niger sp. n., unnamed species P. (O.) sp. «Wolfkloof¼ and presumably P. (O.) silvicola Gillies 1997; the «Asian group¼ includes P. (O.) album Kluge 2016, P. (O.) regularum Müller-Liebenau Hubbard 1985, P. (O.) malabarensis sp. n., presumably Procloeon julia (Gillies 1949) comb. n. and unnamed species P. sp. «Thailand-3¼, P. sp. «Sulawesi¼ and P. sp. «Philippines¼. New South African species P. (O.) barnardi sp. n. and P. (O.) niger sp. n. are described from South Africa based on larvae, subimagines and imagines of both sexes associated by rearing; among them, P. (O.) barnardi sp. n. was formerly described by Barnard (1932) under the name «Austrocloeon africanum¼, being wrongly regarded to be the species originally described as Cloeon africanum Esben-Petersen 1913. Characters of larva and female subimago of another South African species, P. (O.) sp. «Wolfkloof¼ are described based on a single specimen. Two closely related species, P. (O.) regularum Müller-Liebenau Hubbard 1985 from Sri Lanka and P. (O.) malabarensis sp. n. from India are described based on larvae, subimagines and imagines of both sexes associated by rearing; these two species have 2 (rarely 1 or 3) cross veins in pterostigma, in contrast to other species of Oculogaster which normally have one vein (rarely two veins). Procloeon julia is presumptively placed in Oculogaster based on the presence of one vein in pterostigma. Unnamed species P. sp. «Thailand-3¼, P. sp. «Sulawesi¼ and P. sp. «Philippines¼ are presumably placed in Oculogaster; each is briefly described based on a single larva.

Demoulinia Gillies 1990 and two unnamed genera of the plesiomorphon Protopatellata (Ephemeroptera, Baetidae) from South Africa.

Larvae, subimagines, imagines of both sexes and eggs of Demoulinia crassi (Demoulin 1971) are described based on reared specimens from South Africa. Newly revealed characters testify that Demoulinia Gillies 1990 belongs to the plesiomorphon Protopatellata. Demoulinia includes two species, the South African species D. crassi and the Madagascar species D. insularis Lugo-Ortiz McCafferty 1998 (= D. assimilis Gattolliat 2003 syn. n.). Larvae of these two species differ in structure of claws and paraprocts; imagines and eggs are described for D. crassi only. Larvae of two unnamed species of Protopatellata from South Africa are briefly described and figured; possibly, one of them belongs to africanum [Cloeon], which is the type species Austrocloeon Barnard 1932.