All 835 valid species of caddisflies recorded from Vietnam by the end of 2021 are cataloged. The catalog is annotated with information about reference to original description where the species was described, type locality, depository institution of the type material, habitat where the species has been collected, and distribution. The distribution section covers all countries as well as Vietnamese provinces from where species has been recorded. The catalog is based on records of about 7,600 individuals recorded in literature, of which 69 % of the individuals are males and 31 % are females. With 139 species recorded, the most species rich family in Vietnam is the Hydropsychidae, followed by the Philopotamidae, Leptoceridae and the Hydroptilidae. These four families comprise 50% of the species diversity of caddisflies in Vietnam. By number of species, the smallest families are the Phryganopsychidae and Brachycentridae (two species each) and the Sericostomatidae, Phryganeidae and Limnocentropodidae that are represented by only one species each.

The discovery of the new Agaphylax genus with unique paramere organisation has initiated our lineage sorting oftribes by parameres in the Limnephilinae subfamily applying the principles and procedures of fine phenomics in order toestablish transformation series of the polarized plesiomorphy-apomorphy character states for each limnephiline genera.According to the extraordinary high diversity the paramere that is the stimulatory and titillating structure of the phallic organis a speciation supertrait. This adaptive trait is directly involved in the processes of reproductive isolation and diverging assubtle initial split of lineages producing the incipient sibling species in the recent past of contemporary speciation processes.Contrary, the drastic divergence of the Agaphylax plated paramere is much older, similarly to the many-spined parameres ofthe Hesperophylacini tribe. It has been initiated by drastic combined and synchronous external and internal stochastic effects,processed in ancestral sexual integrative adaptation as well as organised and fixed in older and deeper coalescence events andappears as a character with tribe ranking potential. To open a wider perspective, a systemic relational analysis is required inthe future including other adaptive or neutral character transformation series, due to the burden of taxonomic incongruencesgrounded by chimerism in stochastic genetic reticulation. Traits of species are mixed products coming from various sources.Only character combinations can and ought to be analysed in terms how to classify taxa. We have polarized eight genitaliccharacters additional to parameres for a future analysis of the potential of character combinations.Limnephilinae subfamily is composed of Limnephilini, Chilostigmatini, Chaetopterygini, Stenophylacini and Hesperophylacinitribes and here we established the new Agaphylacini tribe. Based on parameres we have delineated taxa in lineagesorting and described two new genera: Fogophylax gen. nov., Simaphylax gen. nov. and fourteen new species: Anaboliaalsoja, A. hepehupa, Asynarchus kimaros, Limnephilus kerekes, L. maghrebensis, L. oblos, Homophylax beges, H. coros,Chaetopteroides plackovicensis, C. rilaensis, Allogamus ketpar, Platyphylax beshkovi, Pycnopsyche letova and P. telea spp.nov. The by-product of this survey is a world atlas of paramere drawings for the entire Limnephilinae subfamily.

We have recognised significant incongruences among the most commonly used taxonomic characters in theEuropean species of Wormaldia genus of the Philopotamidae caddisfly family. During taxonomical analysis and rankingprocedures we have recorded incongruent, discorcordant characters also in the taxa in Rhyacophilidae, Hydropsychidae andLimnephilidae caddisfly families. Based on theoretical background we concluded that taxa of examined caddisflies andprobably all living creatures are chimeric entities composed of components of different origin. Genomes and phenomes aretree-like on the surface but more reticulated in the deep. We understand chimerism with universal consequences, expandingwell beyond the evolutionary tree-thinking of reductionism and determinism. Taxa are chimeric or at least chimerical in astochastic universe under the permanent fluxes of the external and internal impacts created by intercourses between entropyand energy gradients. We have surveyed how to create and correct synonymies in the splitter/lumper perspectives along theprinciples of compositional and specification hierarchies understood as quantitative variability of non-adaptive neutral andqualitative stability of adaptive, non-neutral traits. We outlined how the apophantic (declaratory) hybris creates synonymiesand underestimates biodiversity. After redrawing the diverging genitalic structures, particularly the speciation traits we havereinstated species status of eight taxa: W. trifida Andersen, 1983 stat.restit, stat. nov., W. albanica Oláh, 2010 stat. restit., W.bulgarica Novak, 1971 stat. nov., W. daga Oláh, 2014 stat. restit., W. graeca Oláh, 2014 stat. restit., W. busa Oláh, 2014 stat.restit., W. homora Oláh, 2014 stat. restit. W. nielseni Moretti, 1981 stat. nov. Character selection and lineage sortingprocedures established the following species groups, species complexes and species clades in the European species ofWormaldia: W. occipitalis species group: W. occipitalis species complex; W. charalambi species group; W. copiosa speciesgroup; W. triangulifera species group: W. bulgarica species complex, W. khourmai species complex, W. subnigra speciescomplex: W. asterusia species clade, W. subnigra species clade, W. vercorsica species clade; W. triangulifera speciescomplex, W. variegate species complex. Unplaced species: W. ambigua, W. algirica, W. sarda. In this revision we havedescribed fourteen new species: W. longiseta, W. carpathica, W. kurta, W. parba, W. foslana, W. kumanskii, W. libohova, W.silva, W. gorba, W. kera, W. rona, W. sima, W. granada, W. telva.

The rare and beautifully colourful old-world Parasetodes is a so-called set-aside genus with unsettled taxonomy. For instance, a recent survey (Malicky 2006) has synonymised all the Palaearctic and Oriental species to the type species Parasetodes respersellus (Rambur, 1842). The diverse forewing pattern, as a potential diagnostic character state is liable to disappear rapidly in alcohol or denuded and faded even on dry pinned specimens. In this revision we have delineated species by the ventral, surface-perpendicular profile of the dorsal arm of gonopod, the titillating plate, as well as by the lateral profile of the phallic organ and increased the species number of the genus from 12 to 45 describing 33 new species from the Palaearctic, Oriental, and Afrotropical fauna regions. Palaearctic fauna region: Parasetodes temirlik Oláh & Salokannel, sp. nov., Oriental fauna region: P. bali Oláh, sp. nov., P. baoloc Oláh, sp. nov., P. borneo Oláh & Mey, sp. nov., P. dalat Oláh, sp. nov., P. gunung Oláh & Mey, sp. nov., P. hoang Oláh, sp. nov., P. indicus Oláh, sp. nov., P. kambait Oláh & Johanson, sp. nov., P. lamdong Oláh, sp. nov., P. madacus Oláh & Johanson, sp. nov., P. maechaem Oláh & Mey, sp. nov., P. maehong Oláh & Mey, sp. nov., P. namgen Oláh & Johanson, sp. nov., P. nokrek Oláh & Mey, sp. nov., P. pahang Oláh, sp. nov., P. ratnapur Oláh, sp. nov., P. sinicus Oláh, sp. nov., P. tumbang Oláh & Me,y sp. nov., P. umran Oláh & Mey, sp. nov. Afrotropical fauna region: P. amboas Oláh, sp. nov., P. ambovom Oláh, sp. nov., P. barnardi Oláh, Johanson, Mey & Salokannel, sp. nov., P. caprivi Mey & Oláh, sp. nov., P. ikeleng Oláh & Johanson, sp. nov., P. kindam Oláh, sp. nov., P. mahajan Oláh & Johanson, sp. nov., P. meyan Oláh, sp. nov., P. rwandicus Oláh & Me,y sp. nov., P. sikasso Oláh & Johanson, sp. nov., P. tinko Oláh & Johanson, sp. nov., P. weytus Mey & Oláh, sp. nov., P. zambicus Oláh & Johanson, sp. nov. We have reinstated the species status of P. aquilonius Yang & Morse, 1997 stat. restit., P. ussuriensis Martynov, 1935 stat. restit., P. bakeri (Banks, 1913) stat. restit., P. kiangsinicus (Ulmer, 1932) stat. restit., P. maculatus (Banks, 1911) stat. restit., raised the taxonomic status from subspecies to species rank of Parasetodes tanganicanus Marlier, 1956 stat. nov., and transferred Triaenodes demoulini Jacquemart, 1966 to Parasetodes as P. demoulini (Jacquemart, 1966) comb. nov.

The poorly known, so called widely distributed and highly varying species of the European Rhyacophila fasciata species complex are revised by fine phenomics of the paramere organisation. In this species complex paramere is the most diverse organ. It is the speciation trait integrating the initial split of speciation by its stimulatory and titillating function involved in the early processes of reproductive isolation. Based on paramere organisation and on the character state of distribution three lineages have been delineated in the Rhyacophila fasciata species complex: the European R. fasciata lineage, the Caucasian R. aliena lineage and the R. mysica lineage distributed from Albania to Pakistan. In the R. fasciata lineage we have distinguished three clades of species: R. fasciata with five species, R. matrensis with seven species, and R. denticulata with seven species. We have re-diagnosed three known species: R. fasciata Hagen, 1859, R. denticulataMcLachlan, 1879, R. sociata Navas, 1916 and described 15 species new to science: R. biharensis Oláh sp. nov., R. bulgarica Oláh sp. nov., R. coppai Oláh sp. nov., R. csornahorensis Oláh & Szczęsny sp. nov., R. ferda Oláh sp. nov., R. kopasa Oláh & Coppa sp. nov., R. matrensis Oláh, & Szczęsny sp. nov., R. retezatensis Oláh sp. nov., R. rova Oláh & Coppa sp. nov. R. ruda Oláh & Johanson sp. nov., R. salfa Oláh sp. nov., R. soreda Coppa & Oláh sp. nov. R. suna Oláh sp. nov., R. tuhega Oláh sp. nov., R. zemplenensis Oláh sp. nov. The species status of Rhyacophila gemella Navas, 1923 was reinstated.

The overall declining state of the western taxonomy is clearly documented by the present fate of the extremely high valued and huge unidentified caddisfly material collected in India and deposited in the Canadian National Collection. Due to the general lack of both financial and scientific resources in taxonomy, this huge collection remained almost untouched during the last 70 years after its collection. With a tribute to the collector, Fernand Schmid, the great caddisfly collector and taxonomist we have reconstructed his collecting activities of the five years in India by geolocalization and elaborated about ten percent of his undetermined Hydropsychidae in the Diplectroninae and Hydropsychinae subfamilies. Description of 145 new species from this small fragment of the huge unidentified collection demonstrates a pronounced underestimation of the biodiversity in general, routinely measured by gross phenomics. During this study we have reinstated the species status of seven taxa: Diplectrona kirimaduhela Schmid, 1958, stat. restit., Cheumatopsyche rienga Oláh & Johanson, 2008, stat. restit., Cheumatopsyche amurensis Martynov, 1934, stat. restit., Cheumatopsyche banksi Mosely, 1942, stat. restit., Cheumatopsyche processuata (Martynov, 1927), stat. restit., Potamyia klakahana (Ulmer, 1951), stat. restit., Potamyia proboscida Li & Tian, 1996, stat. restit., and raised the subspecies status to species rank of Diplectrona stigmatica Banks, 1937, stat. nov. Furthermore, we have etablished four new species groups, sixteen new species complexes and described 145 new species as follows: Diplectrona aurovittata new species group: D. hasada new species complex: D. bandara sp. nov., D. borghata sp. nov., D. chiangma sp. nov., D. chingsa sp. nov., D. daotama sp. nov., D. grimona sp. nov., D. jaraina sp. nov., D. khopurna sp. nov., D. khumyara sp. nov., D. kualagomba sp. nov., D. kurlingha sp. nov., D. lyngkota sp. nov., D. mawkhapa sp. nov., D. mirgona sp. nov., D. muktapura sp. nov., D. mynsoa sp. nov., D. nongina sp. nov., D. nongra sp. nov., D. nongronga sp. nov., D. sirkasha sp. nov., D. sironga sp. nov., D. sumatrana sp. nov., D. tairenpokpa sp. nov., D. tungpa sp. nov., D. tamdaophila new species complex: D. aisahka sp. nov., D. beluma sp. nov., D. dhampa sp. nov., D. dhankuta sp. nov., D. huishua sp. nov., D. khasiaca sp. nov., D. khasigupta sp. nov., D. madonga sp. nov., D. meghalaya sp. nov., D. mopaenga sp. nov., D. parala sp. nov., D. rumkhenga sp. nov., D. sitahoana sp. nov., D. sohra sp. nov., D. coalescens species group: D. hongkonga sp. nov., D. kattalaimala sp. nov., D. shimoga sp. nov., D. gombak new species group: D. albofasciata new species complex, D. fasciata new species complex: D. buitenzorga sp. nov., D. panaona sp. nov., D. simalura sp. nov., D. tonkulana sp. nov., D. wailima sp. nov., D. gentinga new species complex: D. gentinga sp. nov., D. gombak new species complex: D. barisana sp. nov., D. merangira sp. nov., D. phanoma sp. nov., D. temengora sp. nov., D. tengaha sp. nov., D. taprobanes new species group: D. abmaka sp. nov., D. kambaita sp. nov., D. kamikarka sp. nov., D. koda sp. nov., D. komadia sp. nov., D. madhya sp. nov., D. satanwada sp. nov., D. sirtranga sp. nov., D. tienmua sp. nov., D. umlanga sp. nov., Cheumatopsyche lepida species group: C. assamha sp. nov., C. fordula sp. nov., C. madpradha sp. nov., C. manimapa sp. nov., C. pondora sp. nov., C. puramukta sp. nov., C. purmapa sp. nov., C. sohkha sp. nov., C. swampa sp. nov., C. dubitans species group: C. mawpya sp. nov., C. excisa species group: C. chuga sp. nov., C. costalis species group: C. dangchura sp. nov., C. kamposka sp. nov., C. lagaironga sp. nov., C. mawjana sp. nov., C. mawprana sp. nov., C. nonga sp. nov., C. nongajra sp. nov., C.oinamla sp. nov., C. salaka sp. nov., C. yunnana sp. nov., C. concava species group: C. haflonga sp. nov., C. kambirona sp. nov., C. khasia sp. nov., C. korosa sp. nov., C. myntanga sp. nov., C. nongrima sp. nov., C. chinensis species group: C. bandarkhala sp. nov., C. delhia sp. nov., C. hanoia sp. nov., C. hotaya sp. nov., C. pega sp. nov., C. quangchua sp. nov., C. tamda sp. nov., C. tongoma sp. nov., C. holzschuhi species group: C. apuma new species complex: C. apuma sp. nov., C. nyukma sp. nov., Potamyia czekanovskii species group: P. flavata new species complex: P. binhoa sp. nov., P. chitwana sp. nov., P. congsa sp. nov., P. moccha sp. nov., P. nikalandugola species complex: P. hasalaka sp. nov., P. tamilnada sp. nov., P. chinensis species group, P. flava species group: P. dinamla sp. nov., P. trenhona species group: P. barata sp. nov., P. jinhongensis new species complex: P. dhauliana sp. nov., P. yunnanica new species complex: P. namha sp. nov., P. namkhana sp. nov., P. topali sp. nov., P. umbaso sp. nov., P. vietnama sp. nov., Hydromanicus hermosus species group: H. flavoguttatus species complex: H. bukit sp.nov., H. mawpyut sp. nov., H. mawshun sp. nov., H. luctuosus species group nom. nov.: H. asor new species complex: H. shilliang sp. nov., H. eleasar new species complex: H. kambaitiensis sp. nov., H. kamengensis sp. nov., H. kashong sp. nov., H. sikkimensis sp. nov., H. tibetensis sp. nov., H. inferior new species complex: H. darban sp. nov., H. hasad sp. nov., H. jakhand sp. nov., H. khalband sp. nov., H. mattiyang sp. nov., H. mynso sp. nov., H. nondeng sp. nov., H. luctuosus species complex: H. fureses sp. nov., H. garhwal sp. nov., H. khopum sp. nov., H. laitlyn sp. nov., H. manilon sp. nov., H. mapum sp. nov., H. pufok sp. nov., H. thangrain sp. nov., H. tharauyang sp. nov., H. tiyang sp. nov., H. tungnath sp. nov., H. umbonatus new species complex: H. kover sp. nov., H. manisir sp. nov., H. ronghongkung sp. nov., H. sirohis sp. nov., H. spatulatus species group: H. rahung sp. nov., H. spatulatus species cluster.