A Taxonomic List of the Mayflies, Stoneflies and Caddisflies (Insecta: Ephemeroptera, Plecoptera and Trichoptera) of the Sikhote-Alin Biosphere Reserve

Abstract

Three orders of amphibiotic insects were examined from the eastern and western streams of the Sikhote-Alin State Nature Biosphere Reserve, which is located in the southern Russian Far East in the central portion of a mountain range with the same name. Data were obtained on Ephemeroptera, Plecoptera, Trichoptera (EPT) fauna inhabiting streams in the Sikhote-Alin State Nature Biosphere Reserve and its adjacent area. The data were collected by the author from 1980 to 2013. More than 30 thousand larvae and adult EPT were identified, and a systematic list of 220 species was formed. Among them, Ephemeroptera is represented by 63 species from 18 genera and 8 families. Plecoptera is represented by 61 species from 30 genera and 8 families. Trichoptera is represented by 96 species from 49 genera and 20 families. The EPT biodiversity study in the local protected areas is important for assessing the ecological preferences of aquatic organisms and understanding the formation of ecosystem structures under normal conditions, i.e., without anthropogenic influence. In addition, the EPT list is of great value, as it is widely used to control the quality of the environment via the EPT indicator index. The comprehensive list of Ephemeroptera, Plecoptera and Trichoptera (EPT complex) taxonomic species of Central Sikhote-Alin streams is submitted for the first time. In addition, a brief areal EPT fauna analysis is made.

Keywords

Amphibiotic insects ; EPT indicator index ; Sikhote-Alin State Nature Biosphere Reserve ; Southern Russian Far East ; Central Sikhote-Alin

Introduction

Sikhote-Alin State Nature Biosphere Reserve is located in the southern Russian Far East, in the central part of the Eponymous mountain range and on the shore of the Sea of Japan. Its territory is comprised of two clusters (Fig. 1 ), which encompass an area of 401.6 sq km. The mountainous terrain of the Sikhote-Alin mountain range is composed of numerous, complex overlapping mountain ridges. The average height of the mountain peaks is 800 m above sea level. The chaotic cluster of hills is dissected by river valleys, forming a dense (0.7 to 0.9 km per 1 sq km), extensive drainage system, with a variety of streams and basins. The rivers are less than 100 km in length, with average slopes of 50–100‰ and upper reach slopes of 150–200‰.

Fig. 1. Terrain features of the study area.

Rivers flowing from the eastern macroslope are fast, with frequent rapids and occasional small waterfalls. The water temperature in summer rarely rises above 16 °C. The river is more tranquil on the smoother, western macroslope, with water temperatures reaching 19–21 °C on hot days. The rivers are mainly fed by rainfall, which accounts for approximately 70–80% of the total annual river flow. According to various estimates, groundwater contributes to 5–20% of the flow, while snowmelt contributes to 10–20%.

The proximity to the ocean, location on the edge of the huge Eurasian continent and rugged terrain are the reasons for the unique climate of the region, which has a pronounced monsoon season. The annual cumulative temperatures of the growing season, which lasts approximately 150 days, amount to approx. 2000–2500 °С. The annual total precipitation on the eastern macroslope is 800 mm, and 650 mm on the western macroslope, with the majority (75–85%) occurring from April to November.

The watercourses of the Sikhote-Alin mountain range are of mountain and submontane types, with developed alluvial forms. These watercourses are of high commercial fishing value. During the freshwater portion of their lifecycle, juvenile salmon mainly feed on freshwater communities of aquatic insects, including mayflies (Ephemeroptera), stoneflies (Plecoptera) and caddisflies (Trichoptera) (Levanidov, 1969 ). In addition, representatives of these orders are highly sensitive to various types of pollution and environmental changes. These characteristics are unique to these species, and make it possible for them to act as environmental indicators, including the widely used EPT biotic index (Semenchenko, 2004 ). In this regard, EPT fauna identification is important for solving a number of fisheries issues, conducting water quality monitoring and assessing ecosystem states. In addition, the benthic communities sampled in this study do not suffer from anthropogenic influences, providing valuable data for the development of scientific methods for forecasting river ecosystem conditions based on various environmental disturbances.

Despite the fact that mayflies, stoneflies and caddisflies in mountain and submontane streams and rivers are characterized by the highest species diversity, the insects in the streams of the reserve remained virtually unstudied until the 1980s. According to the literature, only 4 species of mayflies (Baikova, 1976  ;  Sinichenkova, 1981 ), 4 species of stoneflies (Zhiltsova et al ., 1975  ; Zhiltsova and Levanidova, 1978  ;  Ricker, 1959 ) and 16 taxa of caddisflies were known, 4 of which have not received any species affiliation (Timofeeva, 1978 ).

Based on a comprehensive study of the species compositions of these three orders of amphibiotic insects, the author has obtained lists of Ephemeroptera (Potikha, 1985  ;  Potikha, 2013 ), Plecoptera (Potikha, 2014 ; Potikha and Zhiltsova, 1996 ; Potikha and Zhiltsova, 2001  ;  Potikha and Zhiltsova, 2005 ) and Trichoptera (Potikha, 1991 ; Potikha, 2001 ; Potikha, 2002  ;  Potikha and Vshivkova, 2013 ). The list is currently comprised of 220 taxa (Ephemeroptera — 63 taxa from 18 genera and 8 families; Plecoptera — 61 taxa from 30 genera and 8 families and Trichoptera — 96 taxa from 49 genera and 20 families). The complete taxonomic EPT list from watercourses of the Central Sikhote-Alin, as well as a brief areal analysis, is presented in the following sections.

Materials and Methods

From 1980 to 2013, the author studied more than 90 streams and basins in the reserve and adjacent territories (Fig. 2 ). Over a thousand larvae samples and three thousand adult samples were collected and analyzed. In total, 30 thousand larvae and adults were identified, and over 2.5 thousand individual insects from scientific collections of academic institutions (ZI RAS, BSI FEB RAS) and MSU were studied. Imagoes were collected in coastal vegetation with traps, sweep nets (during swarming) and light traps. Larvae were collected from the surface of substrates via the forced drift method. Qualitative samples were preserved with 75% ethanol, and quantitative with 4% formalin. The samples are stored in the scientific collections of the Sikhote-Alin State Nature Biosphere Reserve, ZI RAS, BSI FEB RAS and MSU.

Fig. 2. Map of main sampling locations.

Distribution types are listed according to Zhiltsova and Levanidova (1984) . Information from websites was used for compiling the taxonomic list (Ephemeroptera of The World ; Morse  ;  Order Plecoptera ). The taxonomic position of mayflies is listed according to Kluge, 2004  ;  Kluge, 2007 . The Ephemerellidae family classification of Jacobus and McCafferty (2008) was used. In addition, the Cinygmula classification of Wang and McCafferty (2004) was utilized. The names of families, genera within families and species within genera are listed in alphabetical order.

Results and Discussion

The taxonomic EPT complex list from the Sikhote-Alin State Nature Biosphere Reserve can be seen below, with statistics presented in Table 1 . The list includes 220 entries belonging to 97 genera and 36 families.

Table 1. The number of EPT complex taxa in the Sikhote-Alin State Nature Biosphere Reserve and adjacent territories.

Oder	Families	Genera	Species
Ephemeroptera	8	18	63
Plecoptera	8	30	61
Trichoptera	20	49	96
Total	36	97	220

Taxonomic List

Order Ephemeroptera

Family Ephemeridae

Ephemera orientalis McLachlan, 1875

Ephemera strigata Eaton, 1892

Ephemera sachalinensis Matsumura, 1911

Family Polymitarcyidae

Ephoron shigae (Takahashi, 1924)

Family Heptageniidae

Cinygmula autumnalis Tiunova et Gorovaya, 2012

Cinygmula cava Ulmer, 1928

Cinygmula hirasana Imanishi, 1935

Cinygmula irina Tshernova et Belov, 1982

Cinygmula kurenzovi (Bajkova, 1965)

Cinygmula levanidovi Tshernova et Belov, 1982

Cinygmula putoranica Kluge, 1980

Cinygmula sapporensis (Matsumura, 1904)

Ecdyonurus (Afghanurus ) aspersus Kluge, 1980

Ecdyonurus (Afghanurus ) bajkovae Kluge, 1986

Ecdyonurus (Afghanurus ) scalaris Kluge, 1983

Ecdyonurus (Atopopus ) aurarius Kluge, 1983

Epeorus (Proepeorus ) anatolii Sinitshenkova, 1981

Epeorus (Belovius ) gornostajevi Tshernova, 1981

Epeorus (Belovius ) ninae Kluge, 1995

Epeorus (Belovius ) pellucidus (Brodsky, 1930)

Epeorus (Belovius ) rubeus Tiunova, 1991

Epeorus (Iron) aesculus Imanishi, 1934

Epeorus (Iron) alexandri Kluge et Tiunova, 1989

Epeorus (Iron) maculatus (Tshernova, 1949)

Heptagenia (Heptagenia ) sulphurea (Müller, 1776)

Rhithrogena bajkovae Sowa, 1973

Rhithrogena lepnevae Brodsky, 1930

Rhithrogena sibirica Brodsky, 1930

Family Ameletidae

Ameletus camtschaticus Ulmer, 1928

Ameletus cedrensis Sinitshenkova, 1977

Ameletus inopinatus labiatus Sinitshenkova, 1981

Ameletus longulus Sinitshenkova, 1981

Ameletus montanus arlecchino Kluge, 2007

Family Siphlonuridae

Siphlonurus immanis Kluge, 1985

Siphlonurus zhelochovtsevi Tshernova, 1952

Siphlonurus sp.

Family Baetidae

Baetis (Baetis) bicaudatus Dodds, 1923

Baetis (Baetis) fuscatus Linnaeus, 1761

Baetis (Baetis) pseudothermicus Kluge, 1983

Baetis (Baetis) ursinus ursinus Kazlauskas, 1963

Baetis (Baetis) vernus Curtis, 1834

Acentrella sibirica (Kazlauskas, 1963)

Baetiella tuberculata (Kazlauskas, 1963)

Сloeon sp.

Family Leptophlebiidae

Leptophlebia (Neoleptophlebia ) japonica (Matsumura, 1931)

Leptophlebia (Paraleptophlebia ) strandii Eaton, 1901

Leptophlebia sp. 1

Leptophlebia sp. 2

Family Ephemerellidae

Drunella aculea Allen 1971

Drunella cryptomeria (Imanishi 1937)

Drunella lepnevae Tshernova 1949

Drunella solida Bajkova 1980

Drunella triacantha Tshernova 1949

Ephemerella aurivillii Bengtsson 1908

Ephemerella f. thymalli

Ephemerella (Hosoba ) atagosana Imanishi 1937

Ephemerella (Zonadia ) kozhovi Bajkova 1967

Ephemerella (Draeconia ) mucronata (Bengtsson 1909)

Cincticostella levanidovae (Tshernova 1952)

Cincticostella tshernovae (Bajkova 1962)

Serratella ignita (Poda 1761)

Serratella setigera (Bajkova 1967)

Serratella zapekinae Bajkova, 1967

Order Plecoptera

Family Taeniopterygidae

Taenionema japonicum (Okamoto, 1922)

Family Nemouridae

Zapada quadribranchiata (Zhiltzova, 1977)

Amphinemura borealis (Morton, 1894)

Amphinemura coreana Zwick, 1973

Amphinemura standfussi Ris, 1902

Amphinemura verrucosa Zwick, 1973

Nemoura arctica Esben-Petersen, 1910

Nemoura despinosa Zhiltzova, 1977

Nemoura geei Wu, 1929

Nemoura nigrodentata Zhiltzova, 1980

Nemoura papilla Okamoto, 1922

Protonemura ermolenkoi Zhiltzova, 1982

Family Capniidae

Capnia aligera Zapekina-Dulkeit, 1975

Capnia nearctica Banks, 1918

Capnia potikhae Zhiltzova, 1996

Capniella ghilarovi Zhiltzova, 1988

Capniella nodosa Klapálek, 1920

Eucapnopsis brevicauda (Claassen, 1924)

Isocapnia arcuata Zhiltzova, 1975

Isocapnia guentheri (Joost, 1970)

Isocapnia kudia Ricker, 1959

Paracapnia khorensis Zhiltzova, 1972

Paracapnia sikhotensis Zhiltzova, 1978

Paracapnia leisteri Zhiltzova et Potikha, 2005

Family Leuctridae

Leuctra fusca (Linnaeus, 1758)

Paraleuctra cercia (Okamoto, 1922)

Paraleuctra zapekinae Zhiltzova, 1974

Perlomyia levanidovae (Zhiltzova, 1975)

Perlomyia secunda (Zapekina-Dulkeit, 1955)

Perlomyia smithae Nelson et Hanson, 1973

Family Pteronarcyidae

Pteronarcys sachalina Klapálek, 1908

Family Perlodidae

Arcynopteryx dichroo (McLachlan, 1872)

Arcynopteryx polaris Klapálek, 1912

Diura majuscula (Klapálek, 1912)

Diura nanseni (Kempny,1900)

Megarcys magnilobus Zhiltzova, 1988

Megarcys ochracea Klapálek, 1912

Megarcys pseudochracea Zhiltzova, 1977

Pictetiella asiatica Zwick et Levanidova, 1971

Skwala compacta (McLachlan, 1872)

Stavsolus manchuricus Teslenko 1999

Isoperla eximia Zapekina-Dulkeit, 1975

Isoperla flavescens Zhiltzova et Potikha, 1986

Isoperla lunigera (Klapálek, 1923)

Isoperla maculata Zhiltzova, 1977

Family Perlidae

Kamimuria exilis (McLachlan, 1872)

Oyamia nigribasis Banks, 1920

Paragnetina flavotincta (McLachlan, 1872)

Family Chloroperlidae

Paraperla lepnevae Zhiltzova, 1970

Utaperla orientalis Nelson et Hanson, 1969

Alloperla deminuta Zapekina-Dulkeit, 1970

Alloperla mediata (Navás, 1925)

Alloperla rostellata (Klapálek, 1923)

Haploperla maritima Zhiltzova et Levanidova, 1978

Suwallia asiatica Zhiltzova et Levanidova, 1978

Suwallia decolorata Zhiltzova et Levanidova, 1978

Suwallia kerzhneri Zhiltzova et Zwick, 1971

Suwallia talalajensis Zhiltzova, 1976

Suwallia teleckojensis (Šámal, 1939)

Sweltsa illiesi Zhiltzova et Levanidova, 1978

Sweltsa lepnevae Zhiltzova, 1977

Order Trichoptera

Family Apataniidae

Apatania complexa (Martynov, 1935)

Apatania crymophila MacLachlan, 1880

Apatania zonella (Zetterstedt, 1840)

Family Arctopsychidae

Arctopsyche palpata Martynov, 1934

Family Brachycentridae

Brachycentrus americanus (Banks, 1899)

Brachycentrus japonicus Iwata, 1927

Micrasema (gelidum ) primoricum Botosaneanu, 1990

Family Ecnomidae

Ecnomus tenellus (Rambur, 1842)

Family Glossosomatidae

Agapetus inaequispinosus Schmid, 1970

Agapetus levanidoruv Vshivkova et Morse, sp.n.

Electragapetus martynovi Vshivkova et Arefina, 1996

Electragapetus praeteritus Martynov, 1934

Glossosoma (Anagapetus) schmidi Levanidova, 1979

Glossosoma (Synafophora ) altaicum Martynov, 1914

Glossosoma (Synafophora ) angaricum (Levanidova, 1967)

Glossosoma (Synafophora) intermedium (Klapálek, 1892)

Glossosoma (Synafophora ) ussuricum (Martynov, 1934)

Family Goeridae

Archithremma ulachensis Martynov, 1935

Goera parvula Martynov, 1935

Goera squamifera Martynov, 1909

Goera tungusensis Martynov, 1909

Family Hydrobiosidae

Apsilochorema sutshanum Martynov, 1934

Family Hydropsychidae

Cheumatopsyche infascia Martynov, 1934

Hydropsyche orientalis Martynov, I934

Hydropsyche sp.

Potamyia czekanovskii (Martynov, 1910)

Family Hydroptilidae

Hydroptila spinosa Arefina et Armitage, 2003

Orthotrichia tragetti Mosely, 1930

Oxyethira ecornuta Morton, 1893

Family Lepidostomatidae

Lepidostoma albardanum (Ulmer, 1906)

Lepidostoma elongatum Martynov, 1935

Lepidostoma sinuatum Martynov, 1935

Family Leptoceridae

Ceraclea excisa (Morton, 1904)

Ceraclea sibirica (Ulmer, 1906)

Mystacides bifida Martynov 1924

Mystacides sibirica Martynov 1935

Oecetis lacustris (Pictet, 1834)

Oecetis nigropunctata Ulmer, 1908

Triaenodes (Ylodes ) levanidovae Morse et Vshivkova, 1997

Triaenodes unanimis MacLachlan, 1877

Family Limnephilidae

Asynarchus amurensis (Ulmer, 1905)

Brachypsyche rara (Martynov, 1914)

Brachypsyche sibirica (Martynov, 1924)

Brachypsyche sp. N

Chilostigma sieboldi MacLachlan, 1876

Chilostigmodes forcipatus Martynov, 1914

Dicosmoecus jozankeanus (Matsumura, 1931)

Ecclisomyia kamtshatica (Martynov, 1914)

Hydatophylax grammicus (MacLachlan, 1880)

Hydatophylax nigrovittatus (MacLachlan, 1872)

Hydatophylax soldatovi (Martynov, 1914)

Hydatophylax variabilis (Martynov, 1910)

Lenarchus productus (Morton, 1896)

Limnephilus alienus Martynov, 1914

Limnephilus correptus MacLachlan, 1880

Limnephilus fenestratus (Zetterstedt, 1840)

Limnephilus picturatus MacLachlan, 1875

Limnephilus quadratus Martynov, 1914

Limnephilus sericeus (Say, 1824)

Limnephilus stigma Curtis, 1834

Limnephilus sp. aff. subcentralis Brauer, 1857

Limnephilus tiunovae Arefina et Levanidova, 1996

Nemotaulius admorsus (MacLachlan, 1866)

Nemotaulius mutatus (MacLachlan, 1872)

Philarctus rhomboidalis Martynov, 1924

Pseudostenophylax amurensis (MacLachlan, 1880)

Family Molannidae

Molanna moesta Banks, 1906

Molannodes tinctus (Zetterstedt, 1840)

Family Philopotamidae

Dolophilodes (Dolophilodes ) affinis Levanidova et Arefina, 1996

Dolophilodes mroczkowskii Botosaneanu, 1970

Kisaura aurascens (Martynov, 1934)

Wormaldia niiensis Kobayashi, 1985

Family Phryganeidae

Agrypnia czerskyi (Martynov, 1924)

Agrypnia picta Kolenati, 1848

Hagenella sibirica (Martynov, 1909)

Oligothricha lapponica (Hagen, 1864)

Semblis atrata (Gmelin, 1789)

Semblis phalaenoides (Linnaeus, 1758)

Family Phryganopsychidae

Phryganopsyche latipennis (Banks, 1906)

Family Psychomyiidae

Metalype uncatissima (Botosaneanu 1970)

Paduniella uralensis Martynov, 1914

Family Rhyacophilidae

Rhyacophila angulata Martynov, 1910

Rhyacophila coreana Tsuda, 1940

Rhyacophila depressa Martynov, 1910

Rhyacophila impar Martynov, 1914

Rhyacophila kardakoffi Navás, 1926

Rhyacophila kawamurae Tsuda, 1940

Rhyacophila lata Martynov, 1918

Rhyacophila lepnevae Levanidova, 1977

Rhyacophila monstrosa Levanidova et Schmid, 1977

Rhyacophila narvae Navás, 1928

Rhyacophila retracta Martynov, 1914

Rhyacophila sutchanica Schmid et Levanidova, 1986

Family Stenopsychidae

Stenopsyche marmorata Navás, 1920

Family Uenoidae

Neophylax relictus (Martynov, 1935)

Neophylax ussuriensis (Martynov, 1914)

The EPT fauna of the Sikhote-Alin State Nature Biosphere Reserve are characterized by a large species diversity, which is representative of fauna from the Russian Far East. Ephemeroptera comprises approximately 36% (Tiunova, 2012 ) of the fauna in the Russian Far East, while Plecoptera accounts for nearly 44% (Teslenko, 2007 ) and Trichoptera roughly 24 (Ivanov, 2011 ).

The mayfly fauna in Sikhote-Alin State Nature Biosphere Reserve and adjacent territory watercourses are dominated by the Heptageniidae (24 species) and Ephemerellidae (15 species) families, followed by the Baetidae (8 species), Ameletidae (5 species) and Leptophlebiidae (4 species) families. The Ephemeridae and Siphlonuridae families are comprised of 3 species each, while Polymitarcyidae is represented by only one species.

The greatest number of stonefly species were in the Perlodidae (14 species), Chloroperlidae (13 species), Capniidae (12 species) and Nemouridae (11 species) families. The Leuctridae family includes 6 species, Perlidae 3 species and Taeniopterygidae and Pteronarcyidae only one species each.

The greatest number of caddisflies species were registered in the Limnephilidae (26 species) family, followed by Rhyacophilidae (12 species), Glossosomatidae (9 species), Leptoceridae (8 species) and Phryganeidae (6 species). Other families consist of 2–4 species, and the Arctopsychidae, Ecnomidae, Hydrobiosidae, Phryganopsychidae and Stenopsychidae families include only one species each.

Data on taxonomic composition should not be considered definitive, as ongoing research from Kolumbe River (Bolshaya Ussurka River basin), and in a new territory, suggests that the taxonomic list will be further updated with new species.

All amphibiotic insects identified up to the species level are summarized in two groups based on the type of distribution: the Holarctic and Palearctic groups (Table 2 ). In the Holarctic group, two types of habitats were identified, the circumpolar type, which widely covers the Palaearctic and Nearctic regions, and the amphi-Pacific type, which is spread throughout the East Asian Palearctic sector and north-western mountainous Nearctic regions, including a strip along the coast of the Arctic Ocean. In the second group, three types of habitats were identified, including the Trans Palearctic, East Palaearctic and Palearchaearctic groups. The Trans Palearctic group includes species that are both disjunctive and widespread in the Palearctic, while the East Palaearctic group combines species commonly found to the east of the Yenisei River and inhabiting areas along the west coast of the Pacific Ocean.

Table 2. Biogeographical composition of the EPT fauna complex of the Sikhote-Alin State Nature Biosphere Reserve.

Distribution type	Mayflies		Stoneflies		Caddisflies		All groups
	N	%	N	%	N	%	N	%
Holarctic group
Circumpolar	1	1.7	3	4.9	13	14.0	17	8.0
Amphi-Pacific	1	1.7	2	3.3	1	1.1	4	2.0
Palaearctic group
Palearchaearctic
Mainland	10	17.2	20	32.8	14	15.0	44	20.7
Mainland-island	7	12.1	5	8.2	17	18.3	29	13.7
East Palaearctic	33	56.9	28	45.9	30	32.3	91	42.9
Trans Palearctic	6	10.4	3	4.9	18	19.3	28	12.7
Total	58		61		93		212

Remark. N — number of taxa identified up to the species level.

In general, the EPT species of rivers and water basins in the Sikhote-Alin State Nature Biosphere Reserve are heterogeneous in biogeographic composition (Table 2 ). They are characterized by a high number of Palaearctic group species, nearly 90.0% (191 species). Within the Palaearctic group, the contribution of East Palaearctic species is the most significant at 42.9% (91 species). These are followed by species within the Palearchaearctic distribution (34.4%; 73 species), of which a portion are characterized as mainland subregion distribution dominate (20.7%; 44 species). Species within the Trans Palearctic distribution type occupy a subordinate position at 12.7% (28 species). The Holarctic group is not numerous and is represented by a total of 21 species (10.0%).

A diversity can be observed in the species correlations within the East Palaearctic and Palearchaearctic habitat types. For example, among mayflies, East Palaearctic species significantly dominate over Palearchaearctic species, constituting 56.9% and 29.3%, respectively. Among stoneflies and caddisflies, the species correlations within the East Palaearctic and Palearchaearctic habitat types are insignificant. However, stoneflies are dominated by East Palaearctic species (45.9%), while caddisflies are dominated by Palearchaearctic species (33.3%). Stoneflies (20 species) and mayflies (10 species) prevail among Palearchaearctic species, the distribution of which is limited to the mainland subregion. Species common in the mainland-island subregion are predominantly caddisflies (17 species). Palearctic species, which are widely distributed, constitute only 4.9% of all stoneflies, while their portions of mayflies and caddisflies are higher, at 10.4% and 19.3%, respectively. Only two mayfly species are registered in the Holarctic group (3.4%), including circumboreal Ephemera mucronata and amphi-Pacific Baetis (B.) bicaudatus . Stoneflies are represented by five species (8.2%), and among them there are three species with amphi-Bering distribution and two species with amphi-Pacific distribution. Caddisfly species are the most abundant in the Holarctic group (14 species, 5.1%).

In addition, three species, Ecnomus tenellus , Molanna moesta and Oecetis lacustris , reach beyond the Holarctic region in their distribution. The first species is found in the Oriental and Afrotropical regions, and the other two in the Oriental region ( Morse ). This species correlation by habitat type is typical of the southern Russian Far East and reflects the general fauna formation laws in this region ( Vshivkova, 1995 ; Sinichenkova, 1981  ;  Tiunova, 2012 ).

In summary, this study of taxonomic EPT complex diversity at a local scale not only provides valuable information for solving biogeographic problems but also serves as a basis for assessing the ecological preferences of aquatic organisms and understanding the formations of ecosystem structures in a natural environment. Although the Reserve is free of human influence, the results can also be used for monitoring areas subjected to anthropogenic stress.

Acknowledgments

The author would like to thank the staff of the Sikhote-Alin State Nature Biosphere Reserve — M.V. Podushko, G.P. Averkova, S.V. Elsukov, N.V. Kholushkina and N.V. Vasilenko for the interesting findings. Special thanks to the staff of BSI FEB RAS — T.M. Tiunova, L.A. Teslenko, T.S. Vshivkova and T.I. Arefina-Armitage, as well as ZI RAS employee L.A. Zhiltsova, for their invaluable advice and assistance in identifying the samples.

References

1. Baikova, 1976 O.Ya. Baikova; On the knowledge of larvae of mayflies of order Paraleptophlebia (Ephemeroptera, Paraleptophlebiidae); Zool. Bull., 5 (1976), pp. 64–68 (in Russian)
2. Ephemeroptera of The World Ephemeroptera of The World; http://www.insecta.bio.spbu.ru/z/Eph-spp/Contents.htm
3. Ivanov, 2011 V.D. Ivanov; Caddisflies of Russia: fauna and biodiversity; Zoosymposia, v. 5, Magnolia Press (2011), pp. 171–209 (www.mapress.com/zoosymposia)
4. Jacobus and McCafferty, 2008 L.M. Jacobus, W.P. McCafferty; Revision of Ephemerellidae Genera (Ephemeroptera); Trans. Am. Entomol. Soc., 134 (1–2) (2008), pp. 185–274
5. Kluge, 2004 N.J. Kluge; The Phylogenetic System of Ephemeroptera; Kluwer Academic Publishers (2004) (456 pp.)
6. Kluge, 2007 N.J. Kluge; Review of Ameletidae (Ephemeroptera) of Russia and adjacent lands; Russ. Entomol. J., 16 (3) (2007), pp. 245–258
7. Levanidov, 1969 V.Ya. Levanidov; Reproduction of Amur Salmon and Forage Base of Their Youth in the Tributaries of Amur River; (1969) (Vladivostok. 242 pp. (in Russian))
8. Morse J.C. Morse; Trichoptera World Checklist; http://entweb.clemson.edu/database/trichopt/index.htm (Accessed 12 May 2013)
9. Order Plecoptera Order Plecoptera; Species file; http://plecoptera.speciesfile.org/Common/basic/Taxa.aspx?TaxonNameID=1152749
10. Potikha, 1985 E.V. Potikha; Preliminary Results of the Study of Mayflies — Ephemeroptera of Sikhote-Alin Biosphere Reserve//Sikhote-Alin Biosphere Area: Ecological Studies; Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok (1985), pp. 86–99 (in Russian)
11. Potikha, 1991 E.V. Potikha; On the Fauna and Ecology of Caddisflies of Sikhote-Alin Biosphere Reserve//Acta Hydroentomologica Latvica; (1991), pp. 38–45 (Riga)
12. Potikha, 2001 E.V. Potikha; Fauna and community structure of caddisflies (Trichoptera) in Sikhote-Alin Biosphere Reserve and adjacent territories; Readings in the Memory of Vladimir Yakovlevich Levanidov, vol. 1, Dalnauka, Vladivostok (2001), pp. 144–151 (in Russian)
13. Potikha, 2002 Ye.V. Potikha; The Trichoptera of the Sikhote-Alin State Biosphere Nature Reserve and adjacent unprotected territories; Proc. 10-th Int. Symp. Trichoptera — Nova Suppl. Ent., Keltern, 15 (2002), pp. 365–374 (c. S.)
14. Potikha, 2013 E.V. Potikha; Mayflies (Ephemeropera) of Sikhote-Alin Biosphere Reserve//X Far Eastern Conference on reserve management; Blagoveshchensk, 25–27 September 2013: Proceedings of the Conference, BSPU Publishers, Blagoveshchensk (2013), pp. 261–264 (in Russian)
15. Potikha, 2014 E.V. Potikha; On the fauna of stoneflies (Insecta: Plecoptera) in Sikhote-Alin Biosphere Reserve and adjacent territories; Readings in Memory of Vladimir Yakovlevich Levanidov, vol. 6, Dalnauka, Vladivostok (2014), pp. 529–542 (in Russian)
16. Potikha and Vshivkova, 2013 E.V. Potikha, T.S. Vshivkova; New data on the fauna of caddisflies (Trichoptera) in Sikhote-Alin Biosphere Reserve//hydroentomology in Russia and neighboring countries; Proceedings of the V Russian Symposium on Amphibiotic and Aquatic Insects/I.D. Papanin Institute of Biology of Inland Waters RAS, Filigran Publishers, Yaroslavl (2013), pp. 134–139 (in Russian)
17. Potikha and Zhiltsova, 1996 E.V. Potikha, L.A. Zhiltsova; On the fauna and ecology of stoneflies (Plecoptera) of Sikhote-Alin Biosphere Reserve; Entomol. Rev., LXXV (3) (1996), pp. 567–573 (in Russian)
18. Potikha and Zhiltsova, 2001 E.V. Potikha, L.A. Zhiltsova; Fauna of stoneflies (Plecoptera) in Sikhote-Alin State Biosphere Reserve//Fauna, environmental issues, ethology and physiology of amphibiotic and aquatic insects in Russia; Proceedings of the VI Russian Trichopterological Symposium, I Russian Symposium on Amphibiotic and Aquatic Insects. Voronezh (2001), pp. 49–54 (in Russian)
19. Potikha and Zhiltsova, 2005 E.V. Potikha, L.A. Zhiltsova; Fauna of stoneflies in Central Sikhote-Alin with description of a new species; Zool. J., 84 (9) (2005), pp. 1086–1091 (in Russian)
20. Ricker, 1959 W.E. Ricker; The species of Isocapnia Banks (Insecta, Plecoptera, Nemouridae); Canad. J. Zool., 37 (5) (1959), pp. 639–653
21. Semenchenko, 2004 V.P. Semenchenko; Principles and Systems of Bioindication of Flowing Waters; Orekh, Minsk (2004), p. 124
22. Sinichenkova, 1981 N.D. Sinichenkova; New Species of Mayflies of Order Ameletus Eaton (Ephemeroptera, Siphlonuridae) From Sikhote-Alin//Invertebrates in Ecosystems of Salmon Rivers in the Far East  ; Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok (1981), pp. 73–78 (in Russian)
23. Teslenko, 2007 V.A. Teslenko; Review of the fauna of stoneflies (Plecoptera) and zoning of watercourses of Russias Far East; Eurasian J., 6 (2) (2007), pp. 157–180
24. Timofeeva, 1978 T.A. Timofeeva; Caddisflies (Trichoptera) of Serebryanka River Basin; (Thesis) Tomsk State University, Tomsk (1978) (52 pp. (Archival materials of Sikhote-Alin Reserve). [in Russian])
25. Tiunova, 2012 T.M. Tiunova; Mayfly biodiversity (Insecta, Ephemeroptera) of the Russian Far East; Eurosian Entomol. J., 11 (Suppl. 2) (2012), pp. 27–34
26. Vshivkova, 1995 T.S. Vshivkova; Hydrobiological studies in the Ussuri Reserve named after Academician V.L. Komarov; Part I. Freshwater Fauna (Taxonomic and Biogeographical Composition), Dalnauka, Vladivostok (1995) (40 pp. (in Russian))
27. Wang and McCafferty, 2004 T.-Q. Wang, W.P. McCafferty; Heptageniidae (Ephemeroptera) of the world. Part I: phylogenetic higher classification; Trans. Am. Entomol. Soc., 130 (1) (2004), pp. 11–45
28. Zhiltsova and Levanidova, 1978 L.A. Zhiltsova, I.M. Levanidova; New species of stoneflies (Plecoptera) from the Far East//new species of animals; Trans. Zool. Inst. AS USSR, 61 (1978), pp. 3–29 (in Russian)
29. Zhiltsova and Levanidova, 1984 L.A. Zhiltsova, I.M. Levanidova; Annotated catalogue of stoneflies (Plecoptera) of the Far East of USSR//fresh water biology of Far East; Transactions of Biology and Soil Institute FESC AS USSR, Far Eastern Scientific Center, AS USSR, Vladivostok (1984), pp. 18–45 (in Russian)
30. Zhiltsova et al., 1975 L.A. Zhiltsova, Yu.I. Zapekina-Dulkeit, I.M. Levanidova; Palearctic species of the order Isocapnia Banks (Plecoptera, Capniidae)  ; Entomol. Rev., 54 (3) (1975), pp. 565–576 (in Russian)