Zoosymposia

**Stonefly drumming behavior descriptions of three Soliperla Ricker, 1952 species (Plecoptera: Peltoperlidae)**

JOHN B. SANDBERG — 2023-07-31

One new drumming call signal description and two updated call descriptions of three Soliperla Ricker, 1952 species in the stonefly family Peltoperlidae are presented. It was determined after recording and analysis that these signals differed from the previous descriptions, warranting a revision. Percussive signal interval patterns for the three species are described for the first time. The previous monophasic call signal pattern descriptions of Soliperla quadrispinula (Jewett, 1954) and S. thyra (Needham & Smith, 1916) are updated to the repeated monophasic pattern. The male call and response of S. sierra Stark, 1983 and the response signal of S. quadrispinula are described for the first time. The call descriptions of the three California species consist of one to six monophasic signals with inconsistent inter-call intervals. Sequenced monophasic female answers did not follow all repeated male calls. Male monophasic responses occasionally followed female answers in sequenced 3-way exchanges.

**Description of Adults of Acentrella nadineae McCafferty, Waltz & Webb, 2009 (Baetidae: Ephemeroptera) with notes on rearing and madicolous behavior of nymphs**

STEVEN K. BURIAN — 2023-07-31

Acentrella nadineae McCafferty, Waltz, & Webb, 2009 is broadly distributed in cool, clean, swift rocky streams across parts of the southeast, northeast, and midwestern United States, but currently its adult stages are unknown. The difficulty associated with successfully rearing nymphs of Acentrella species is mostly responsible for our lack of knowledge of adult life stages. New field observations of A. nadineae nymphs from the Hubbard River, Massachusetts, USA were used to modify an already successful rearing system for baetid nymphs to obtain a reared series of male and female imagos for study. Both life stages were photographed alive and are described herein for the first time. In addition, details of the modified rearing system and notes on the unusual madicolous behavior of near final instar nymphs are presented.

Factors structuring patterns of Ephemeroptera (mayflies) species assemblages in different segments of the Western Ghats of peninsular India—a snapshot

K. G. SIVARAMAKRISHNAN — 2023-07-31

Species assemblage patterns of the mayflies (Ephemeroptera) in different segments of the Western Ghats (WG) of peninsular India including those on “sky islands” are presented. An updated checklist of species of WG mayflies is provided and sorted by traits of individual species and supplemented by personal observations. Comparisons are made in this context with patterns of current distribution of some ancient lineages of myriapods, amphibians and birds from the WG focusing on relative roles of geographical barriers (gaps), paleoclimatic, eco-evolutionary scenarios and anthropogenic impacts. This is to highlight the need to prioritize conservation of this rapidly shrinking precious biological heritage. Future work on molecular aspects of intra- and interspecific diversity of mayflies, which are “sentinels of inland water ecosystem health” should be augmented in tune with current research trends in montane “sky islands” especially from adjacent Oriental tropics.

Mayfly Larvae (Ephemeroptera) in Thailand: Diversity and Science Communication

BOONSATIEN BOONSOONG — 2023-07-31

Mayflies (Ephemeroptera) are one of the most common components of aquatic assemblages in freshwater environments and contribute to ecosystem services. Mayflies have been widely used as indicators of water quality and frequently play an important role in biomonitoring protocols. Mayflies exhibit a decrease in taxa richness with increases in stream or river pollution and degradation. A series of taxonomic studies on Thai mayflies reported 19 families, 73 genera, and approximately 176 species. The families Baetidae and Heptageniidae are the most diverse and widespread groups of Thai mayflies. Our understanding of the diversity of Thai mayflies has steadily increased in recent years. New genera are being described: Cymbalcloeon Suttinun, Gattolliat & Boonsoong, 2020; Elatosara Malzacher, 2020; Megabranchiella Phlai-ngam & Tungpairojwong, 2022; Mekongellina Malzacher, 2019; Sangpradubina Boonsoong & Sartori, 2016; and Thainis Malzacher, 2020. New species and new country records are constantly being discovered in Thailand. Nevertheless, the number of genera and species seems to be lower than the species diversity estimation, and several genera and species remain undescribed. Research on the systematics and ecology of mayflies has been increasing in recent years. DNA barcoding can provide a powerful supplement to the traditional morphological approach to species delimitation. The book entitled “Mayfly Larvae in Thailand” (Thai version) and the boardgame “Thai Mayflies” were developed for environmental science communication. Further efforts are required to assess the conservation status of mayfly species. Thus, data on mayfly diversity and ecological requirements could be used as tools to evaluate environmental impacts on water resources and to drive future research on biodiversity conservation management strategies.

Ecology and phenology of stoneflies (Plecoptera) in the northern slopes of the Central Caucasus in winter and spring seasons

SUSANNA K. CHERCHESOVA — 2023-07-31

The species of winter- and spring emerging plecopterans inhabiting the northern slopes of the Central Caucasus (territory of the Republic of North Ossetia-Alania, Russia) were examined. A total of 33 species were found at 59 sites. These findings expand the knowledge of ecology and phenology of six species for which we knew little. New localities were detected for a few rare stoneflies: Filchneria balcarica Balinsky, 1950, Plesioperla sakartvella (Zhiltzova, 1956), P. brachystyla Zhiltzova, 1988 and others.

Mayflies (Insecta: Ephemeroptera) of the Indian Himalaya and future challenges

M. VASANTH — 2023-07-31

A concise overview of the diversity and distribution of Ephemeroptera of Indian Himalaya, a global biodiversity hotspot, is presented. The current study summarizes the diversity and distribution of Ephemeroptera of the seven Himalayan states of India: Jammu and Kashmir, Ladakh, Himachal Pradesh, Uttarakhand, Utter Pradesh, Sikkim, and Arunachal Pradesh. This study documents 10 families, 34 genera, 89 species. A total of 57 species are considered endemic to the region. The richest diversity is reported from the states of Himachal Pradesh and Arunachal Pradesh and the maximum diversity is seen within three families and three genera. Updated information on Ephemeroptera of the Himalaya parts of Pakistan, Nepal, Bhutan and China is required to comprehensively understand the diversity and endemicity of the hotspot. Further, to advance our knowledge of Ephemeroptera of the region, a synthesis of the taxonomy of adults and larvae with description of all life history stages within a molecular phylogenetic framework is urgently required.

**Water temperature and the growth of Ameletus inopinatus (Ephemeroptera: Ameletidae) in the Cairngorms, Scotland**

CRAIG R. MACADAM — 2023-07-31

Ameletus inopinatus Eaton, 1887 is the only arctic-alpine mayfly species found in the British Isles. Previous research in Europe using climate models has shown that the geographical range of this species is likely to contract as water temperatures increase. As such, A.inopinatus is particularly vulnerable to the impacts of climate warming. The impact of water temperature on the development of A.inopinatus larvae was investigated in the Cairngorms National Park in Scotland. We closely linked larval development to water temperature with snow cover playing an important role in ensuring emergence occurs before watercourses cease to flow in early summer. The results of this study confirm the vulnerability of A. inopinatus to rising water temperatures and provide new information to help target mitigation measures to prevent further losses of this species.

**Using distribution models to identify range shifts of four Acroneuria Pictet, 1841 (Plecoptera: Perlidae) species in the Midwest USA**

PHILLIP N. HOGAN — 2023-07-31

Regional faunal assessments of stoneflies in the United States Midwest (herein defined as Illinois, Indiana, Iowa, Michigan, Minnesota, Ohio, and Wisconsin) indicate increasing imperilment resulting from human disturbance and climate change. Large-bodied perlid stoneflies with multivoltine life cycles are among the most at risk for regional extirpation, with losses reported in several midwestern states. Species distribution modeling was undertaken to describe distribution shifts for four widespread riverine species: Acroneuria abnormis (Newman, 1838), A. frisoni Stark & Brown, 1991, A. internata (Walker, 1852) and A. lycorias (Newman, 1839). The distribution modeling algorithm MaxEnt was selected to predict both the historical (i.e., pre-1960) and contemporaneous distributions for each species using separate occurrence datasets. These models permit the identification of suitable habitat loss through range contractions associated with human disturbance. Predictions of suitable habitat losses were recorded for multiple species but were greatest for A. abnormis and A. internata. These models serve to guide future collection efforts and to further describe patterns of regional biodiversity loss.

Inter-annual and habitat variation of the mayfly assemblage in grassland and pine afforested headwater streams (Córdoba, Central Argentina)

VICTORIA MONTILLA — 2023-07-31

Mayflies are widely used as indicators of stream conditions since their presence and abundance are closely associated with changes in environmental characteristics. We aim to analyze the richness and abundance patterns of mayflies in headwater streams of the Ctalamochita river basin in central Argentina, where some sub-basins have been fully afforested with exotic pines. We sampled 3 grassland streams and 3 pine afforested streams in 2008, 2012, 2014, and 2015. We took Surber samples in riffles and in 2012 we also sampled 2 additional habitats: pools and macrophyte patches. We found ten mayfly genera. Americabaetis and Leptohyphes were the most frequent and abundant and Cloeodes and Tricorythodes were rare, with a relative frequency < 3%. Richness and abundance were higher in grassland streams (ANOVA, p < 0.05), but the abundance pattern of different mayfly genera varied. In 2012 mayfly abundance was higher in pools and macrophytes in the afforested streams (ANOVA, p < 0.05), but it was similar among habitats in grassland streams. Different species dominated different habitats and stream types, and some shared the same habitat. In riffles and pools, the dominant genera was similar for afforested and grassland streams, while in macrophyte the dominance varied according to the riparian vegetation. Distribution patterns are influenced by microhabitat characteristics, which may be conditioned by changes in riparian land uses.

Riparian forests as dispersal corridors for adult European mayflies, stoneflies and caddisflies (EPTs)

ANDRÉS PEREDO ARCE — 2023-07-31

Metacommunity theory connects the diversity patterns of the community across the landscape with the effects of ecological processes. As dispersal is one of the main factors driving the metacommunity structure, it is important to understand the interaction between landscape and dispersal to apply metacommunity theory. Herein, we summarize the main challenges of applying metacommunity theory to the mayfly, stonefly and caddisfly community (Ephemeroptera, Plecoptera and Trichoptera, or EPTs). Then, we attempt to solve some of the open questions regarding EPT dispersal and its relation with riparian forests. First, we investigate the diversity of functional dispersal traits of the European EPT species, analysing the existing empirical data and selecting a suitable functional index. Second, we assess the effect of riparian forest in landscape connectivity for EPTs, concluding that deciduous riparian forest can enhance dispersal. Third, we extend the study to four European regions, concluding that the role of native riparian forest as dispersal corridor differs between regions. We achieved three goals: First, we produced a theoretical and methodological framework to include dispersal in the study of EPT metacommunity, highlighting the role of riparian forest as a dispersal corridor. Second, we identify several aspects that require further investigation such as empirical dispersal studies or interactions between ecological stressors and dispersal. Third, we provide a new perspective for riverine and riparian ecosystems management, highlighting the need to consider riparian buffers as an integral part of the riverine ecosystems.

**Systematics and updated range alter the conservation status of the Louisiana Needlefly, Leuctra szczytkoi Stark & Stewart, 1981 (Plecoptera: Leuctridae)**

SCOTT A. GRUBBS — 2023-07-31

The Louisiana Needlefly, Leuctra szczytkoi Stark & Stewart, 1981, was one of 404 species petitioned in 2010 by the Center for Biological Diversity for inclusion and protection under the United States Endangered Species Act. There were only four known locality records in northern and central Louisiana before the start of this project, all collected between 1973 and 1997. Prior published research, however, provided tangible evidence that L. paleo Poulton & Stewart, 1991 could be a junior synonym of L. szczytkoi. The type localities of these two species (L. paleo—southern Arkansas; L. szczytkoi—northern Louisiana) are only separated by approximately 120 km. The primary objective of this study was to use mitochondrial cytochrome C oxidase subunit 1 gene sequences to assess the taxonomic validity of L. paleo using tree- and genetic distance-based phylogenetic analyses. Results of all analyses provide consistent and strong evidence that L. paleo is a junior synonym of L. szczytkoi. Hence, L. szczytkoi has nomenclatural priority with an expanded known distribution now from southern Arkansas southward to central Louisiana and southwestward to east Texas with 20 unique locations. Additional notes on other members of the L. ferruginea (Walker, 1852) group are provided.

Baetis venkataramani sp. nov., a new species of the genus Baetis Leach, 1815 (Ephemeroptera: Baetidae) from Tamil Nadu, India

T. SIVARUBAN — 2023-07-31

As part of the ongoing research in the southern Western Ghats, a new species of Baetis Leach is described based on the nymphs collected in the Tamil Nadu, Southern India. Baetis venkataramani sp. nov. does not belong to any of the Baetis species groups proposed so far. The most closely related species to B. venkataramani sp. nov. is B. collinus Müller-Liebenau & Hubbard. However, the new species is distinguished from B. collinus by the presence of tergalius I, posterio-tergal spines absent on the tergites I–VIII and present on the tergum IX and by the size of the labial palp segment III. The main differences between B. venkataramani sp. nov. and other oriental species of Baetis are also discussed.

Contribution to the Protonemura Kempny, 1898 (Plecoptera: Nemouridae) of the Caucasus

DÁVID MURÁNYI — 2023-07-31

New records of Protonemura species are enumerated on the basis of specimens collected between 2015 and 2019 in the Greater and Lesser Caucasus. Three new species are proposed on the basis of males, females and nymphs: P. apetor sp. n. from Georgia, P. boris sp. n. from Azerbaijan and Georgia, and P. soad sp. n. from Armenia and Georgia. Comments are given on the variability of the adults of P. spinulata Martynov, 1928 and P. viridis Balinsky, 1950 on the basis of Azerbaijani and Georgian specimens. The hitherto unknown nymph of P. aculeata Theischinger, 1976, P. bacurianica bacurianica Zhiltzova, 1957, P. oreas Martynov, 1928, P. spinulata and P. viridis are described on the basis of association by pharate adults. Protonemura spinulata is new for Armenia, P. triangulata Martynov, 1928 is new for the Lesser Caucasus, and Nemoura dromokeryx Theischinger, 1976 is new for Georgia and the Caucasus. A checklist of the Protonemura species known from Anatolia, the Caucasus, the Alborz and the Levant is presented.

**A review of Asian mayfly species of Habrophlebiodes (Ephemeroptera: Leptophlebiidae)**

XUHONGYI ZHENG — 2023-07-31

The mayfly genus Habrophlebiodes Ulmer, 1920 has four Asian species (three from China). To show the real characters of Asian species and to ensure the differences between the two clades of the genus, we studied all three endemic Chinese species (H. gilliesi Peters, 1963, H. tenella Kang & Yang, 1994, H. zijinensis You & Gui, 1995) with examining specimens from more than 30 sites. Adults of Chinese Habrophlebiodes can be separated by the male genitalia, female ovipositor and spots on adult wings, nymphs can be recognized by the abdominal color and prostheca shape of mandibles. Comparatively, the fourth species H. prominens Ulmer, 1939 is more different by its longer apical segment of maxillary palpi and colored wings. A key to the four Asian species is given. The status of the latter species, the exact difference between Asian and American clades, and their distribution pattern need more fresh materials to confirm.

Proceedings of the 2022 XVI International Conference On Ephemeroptera and XX International Symposium On Plecoptera (Cover)

R. EDWARD DEWALT — 2023-07-31

Proceedings of the 2022 XVI International Conference On Ephemeroptera and XX International Symposium On Plecoptera (Cover)

Proceedings of the 2022 XVI International Conference On Ephemeroptera and XX International Symposium On Plecoptera (Table of Contents)

R. EDWARD DEWALT — 2023-07-31

Proceedings of the 2022 XVI International Conference On Ephemeroptera and XX International Symposium On Plecoptera (Table of Contents)

Preface: Proceedings of the XVIth International Conference on Ephemeroptera and XXth International Symposium on Plecoptera

R. EDWARD DEWALT — 2023-07-31

Because of uncertainty about hosting an international, in-person conference in mid-2021, our meeting was postponed until summer 2022. Uncertainty continued into 2022. We could not wait longer, so The Joint Meeting of the XVI International Conference on Ephemeroptera and XX International Symposium on Plecoptera was a virtual affair hosted from the University of Illinois Urbana Champaign, U.S.A. The conference occurred daily, 0600–0900 hrs Chicago time, 26–29 July 2022. Despite the virtual venue, 41 oral (video) and 26 poster presentations were given by a total of 133 authors, representing 28 countries. At least 196 unique persons attended the 12 hrs of conference. It was a surprisingly successful meeting. The meeting program and links to all presentations are available from Plecoptera Species File. There were no Lifetime Achievement Awards bestowed upon our members during this meeting. A proposal for a meeting in 2024 in Turin, Italy was presented and accepted. In the weeks following the conference, we learned of the tragic death of our good friend and colleague Dr. Boris C. Kondratieff. We dedicate this volume to his memory and provide an obituary in this volume.

Boris Carl Kondratieff, a Lifetime of Scholarship and Service to Aquatic Entomology

R. EDWARD DEWALT — 2023-07-31

It is with great sadness that I share with you the death of Dr. Boris Carl Kondratieff (30 April 1954 to 14 August 2022) (Fig. 1). Boris was a 35 year employee of Colorado State University (CSU). He served as Director of the C. P. Gillette Museum of Arthropod Diversity, a collection of nearly 3.5 million specimens, most of which were amassed after his hire in 1986. He taught many courses at CSU and they were nearly always filled to capacity. Boris served as advisor for some 50 master’s and PhD students. He was highly sought after for graduate committees. His students conducted many high-quality research projects on the taxonomy, biogeography, and ecology of aquatic insects. In later years he collaborated with such luminaries of aquatic ecology as N. LeRoy Poff and James V. Ward, both of CSU.