# List of Hydraena species

This is a list of 924 species in Hydraena, a genus of minute moss beetles in the family Hydraenidae.

## Hydraena species

* Hydraena abbasigili Jäch, 1988$^{icg}$
* Hydraena abdita Orchymont, 1948$^{icg}$
* Hydraena abyssinica Régimbart, 1905$^{icg}$
* Hydraena accurata Orchymont, 1948$^{icg}$
* Hydraena achaica Jäch, 1995$^{icg}$
* Hydraena acumena Perkins, 2011$^{icg}$
* Hydraena adelbertensis Perkins, 2011$^{icg}$
* Hydraena adrastea Orchymont, 1948$^{icg}$
* Hydraena aethaliensis Breit, 1917$^{icg}$
* Hydraena affirmata Perkins, 2007$^{icg}$
* Hydraena affusa Orchymont, 1936$^{icg}$
* Hydraena africana Kuwert, 1888$^{icg}$
* Hydraena akameku Perkins, 2011$^{icg}$
* Hydraena akbesiana Audisio, De Biase and Jäch, 1993$^{icg}$
* Hydraena albai Sáinz-Cantero, 1993$^{icg}$
* Hydraena alberti Balfour-Browne, 1950$^{icg}$
* Hydraena alcantarana Ienistea, 1985$^{icg}$
* Hydraena algerina Kaddouri, 1992$^{icg}$
* Hydraena alia Orchymont, 1934$^{icg}$
* Hydraena aliciae Jäch and Díaz, 2005$^{icg}$
* Hydraena allomorpha Lagar and Fresneda, 1990$^{icg}$
* Hydraena alluaudi Régimbart, 1906$^{icg}$
* Hydraena alpicola Pretner, 1931$^{icg}$
* Hydraena altamirensis Díaz Pazos and Garrido Gonzalez, 1993$^{icg}$
* Hydraena altapapua Perkins, 2011$^{icg}$
* Hydraena alternata Perkins, 1980$^{icg}$
* Hydraena alterra Perkins, 1980$^{icg}$
* Hydraena alticola Skale and Jäch, 2008$^{icg}$
* Hydraena altiphila Perkins, 2011$^{icg}$
* Hydraena amazonica Perkins, 2011$^{icg}$
* Hydraena ambiflagellata Zwick, 1977$^{icg}$
* Hydraena ambigua Ganglbauer, 1901$^{icg}$
* Hydraena ambiosina Perkins, 2007$^{icg}$
* Hydraena ambra Perkins, 2011$^{icg}$
* Hydraena ambripes Perkins, 2011$^{icg}$
* Hydraena ambroides Perkins, 2011$^{icg}$
* Hydraena americana Jäch, 1993$^{icg}$
* Hydraena amidensis Jäch, 1988$^{icg}$
* Hydraena ampla Perkins, 2011$^{icg}$
* Hydraena anaphora Perkins, 1980$^{icg}$
* Hydraena anatolica Janssens, 1963$^{ic}$
* Hydraena ancylis Perkins, 1980$^{icg}$
* Hydraena ancyrae Jäch, 1992$^{icg}$
* Hydraena andalusa Lagar and Fresneda, 1990$^{icg}$
* Hydraena andreinii Orchymont, 1934$^{icg}$
* Hydraena angulicollis Notman, 1921$^{icgb}$
* Hydraena angulosa Mulsant, 1844$^{icg}$
* Hydraena angustata Sturm, 1836$^{icg}$
* Hydraena anisonycha Perkins, 1980$^{icg}$
* Hydraena antaria Perkins, 2007$^{icg}$
* Hydraena antiatlantica Jäch, Aguilera and Hernando, 1998$^{icg}$
* Hydraena antiochena Jäch, 1988$^{icg}$
* Hydraena apertista Perkins, 2011$^{icg}$
* Hydraena apexa Perkins, 2011$^{icg}$
* Hydraena appalachicola Perkins, 1980$^{icg}$
* Hydraena appetita Perkins, 2007$^{icg}$
* Hydraena aquila Perkins, 2011$^{icg}$
* Hydraena arabica Balfour-Browne, 1951$^{icg}$
* Hydraena arachthi Ferro and Jäch, 2000$^{icg}$
* Hydraena arcta Perkins, 2007$^{icg}$
* Hydraena arenicola Perkins, 1980$^{icg}$
* Hydraena argutipes Perkins, 1980$^{icg}$
* Hydraena ariana Janssens, 1962$^{icg}$
* Hydraena arizonica Perkins, 1980$^{icg}$
* Hydraena armata Reitter, 1880$^{icg}$
* Hydraena armatura Perkins, 2014$^{icg}$
* Hydraena armeniaca Janssens, 1968$^{icg}$
* Hydraena armipalpis Jäch and Díaz, 2000$^{icg}$
* Hydraena armipes Rey, 1886$^{icg}$
* Hydraena aroensis (Ferro, 1991)$^{icg}$
* Hydraena arunensis Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena ascensa Perkins, 2007$^{icg}$
* Hydraena assimilis Rey, 1885$^{icg}$
* Hydraena ateneo Freitag, 2013$^{icg}$
* Hydraena athertonica Perkins, 2007$^{icg}$
* Hydraena atrata Desbrochers des Loges, 1891$^{icg}$
* Hydraena atroscintilla Perkins, 2011$^{icg}$
* Hydraena attaleiae Ferro, 1984$^{icg}$
* Hydraena audisioi Jäch, 1992$^{icg}$
* Hydraena aulaarta Perkins, 2011$^{icg}$
* Hydraena aurita Jäch, 1988$^{icg}$
* Hydraena australica Zwick, 1977$^{icg}$
* Hydraena australula Perkins, 2007$^{icg}$
* Hydraena austrobesa Perkins, 2011$^{icg}$
* Hydraena avuncula Jäch, 1988$^{icg}$
* Hydraena bacchusi Perkins, 2011$^{icg}$
* Hydraena bactriana Janssens, 1962$^{icg}$
* Hydraena bakriensis Skale and Jäch, 2011$^{icg}$
* Hydraena balearica Orchymont, 1930$^{icg}$
* Hydraena balfourbrownei Bameul, 1986$^{icg}$
* Hydraena balkei Perkins, 2011$^{icg}$
* Hydraena balli Orchymont, 1940$^{icg}$
* Hydraena barbipes Zwick, 1977$^{icg}$
* Hydraena barricula Perkins, 1980$^{icg}$
* Hydraena barrosi Orchymont, 1934$^{icg}$
* Hydraena bedeli Berthélemy, 1992$^{icg}$
* Hydraena belgica Orchymont, 1930$^{icg}$
* Hydraena beniensis Perkins, 2011$^{icg}$
* Hydraena benjaminus Jäch and Díaz, 2006$^{icg}$
* Hydraena bensae Ganglbauer, 1901$^{icg}$
* Hydraena bergeri (Janssens, 1972)$^{icg}$
* Hydraena berthelemyana Jäch, Díaz and Dia in Jäch, Dia and Díaz, 2006$^{icg}$
* Hydraena berytus Jäch, 1986$^{icg}$
* Hydraena beyarslani Jäch, 1988$^{icg}$
* Hydraena bicarina Perkins, 2014$^{icg}$
* Hydraena bicarinova Perkins, 2011$^{icg}$
* Hydraena bicolorata Jäch, 1997$^{icg}$
* Hydraena bicuspidata Ganglbauer, 1901$^{icg}$
* Hydraena bidefensa Perkins, 2007$^{icg}$
* Hydraena bifunda Perkins, 2011$^{icg}$
* Hydraena bihamata Champion, 1920$^{icg}$
* Hydraena biimpressa Perkins, 2007$^{icg}$
* Hydraena billi Zwick, 1977$^{icg}$
* Hydraena bilobata Jäch and Díaz, 1998$^{icg}$
* Hydraena biltoni Jäch and Díaz, 2012$^{icg}$
* Hydraena bimagua Jäch, 1986$^{icg}$
* Hydraena birendra Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena biseptosa Perkins, 2014$^{icg}$
* Hydraena bispinosa Pu, 1951$^{icg}$
* Hydraena bisulcata Rey, 1884$^{icg}$
* Hydraena bitruncata Orchymont, 1934$^{icg}$
* Hydraena bituberculata Perkins, 1980$^{icg}$
* Hydraena biundulata Perkins, 2011$^{icg}$
* Hydraena blackburni Zaitzev, 1908$^{icg}$
* Hydraena bodemeyeri Jäch and Díaz, 2001$^{icg}$
* Hydraena boetcheri Orchymont, 1932$^{icg}$
* Hydraena bolivari Orchymont, 1936$^{icg}$
* Hydraena boliviana Perkins, 2011$^{icg}$
* Hydraena bononiensis Binaghi, 1960$^{icg}$
* Hydraena borbonica Fairmaire, 1898$^{icg}$
* Hydraena bosnica Apfelbeck, 1909$^{icg}$
* Hydraena brachymera Orchymont, 1936$^{icg}$
* Hydraena bractea Perkins, 1980$^{icg}$
* Hydraena bractoides Perkins, 1980$^{icg}$
* Hydraena brahmin Perkins, 2011$^{icg}$
* Hydraena breedlovei Perkins, 1980$^{icg}$
* Hydraena brevis Sharp, 1882$^{icg}$
* Hydraena britteni Joy, 1907$^{icg}$
* Hydraena brittoni Zwick, 1977$^{icg}$
* Hydraena bromleyae Jäch, 1986$^{icg}$
* Hydraena browni Perkins, 1980$^{icg}$
* Hydraena bubulla Perkins, 2011$^{icg}$
* Hydraena bulgarica Breit, 1916$^{icg}$
* Hydraena buloba Perkins, 2011$^{icg}$
* Hydraena buquintana Perkins, 2011$^{icg}$
* Hydraena buschietanni Freitag, 2021$^{icg}$
* Hydraena buscintilla Perkins, 2011$^{icg}$
* Hydraena busuanga Freitag and Jäch, 2007$^{icg}$
* Hydraena calcarifera Janssens, 1959$^{icg}$
* Hydraena californica Perkins, 1980$^{icg}$
* Hydraena campbelli Perkins, 1980$^{icg}$
* Hydraena canakcioglui Janssens, 1965$^{icg}$
* Hydraena canticacollis Perkins, 1980$^{icg}$
* Hydraena capacis Perkins, 2007$^{icg}$
* Hydraena capensis Perkins, 2014$^{icg}$
* Hydraena capetribensis Perkins, 2007$^{icg}$
* Hydraena cappadocica Jäch, 1988$^{icg}$
* Hydraena caprivica Perkins, 2014$^{icg}$
* Hydraena capta Orchymont, 1936$^{icg}$
* Hydraena carbonaria Kiesenwetter, 1849$^{icg}$
* Hydraena carica Jäch, 1988$^{icg}$
* Hydraena carinocisiva Perkins, 2011$^{icg}$
* Hydraena carinulata Rey, 1886$^{icg}$
* Hydraena carmellita Perkins, 2011$^{icg}$
* Hydraena carniolica Pretner, 1970$^{icg}$
* Hydraena castanea Deane, 1937$^{icg}$
* Hydraena castanescens Freitag and Jäch, 2007$^{icg}$
* Hydraena cata Orchymont, 1936$^{icg}$
* Hydraena catalonica Fresneda, Aguilera and Hernando, 1994$^{icg}$
* Hydraena catherinae Bameul and Jäch, 2001$^{icg}$
* Hydraena caucasica Kuwert, 1888$^{icg}$
* Hydraena cavifrons Perkins, 2011$^{icg}$
* Hydraena cephalleniaca Jäch, 1985$^{icg}$
* Hydraena cervisophila Jäch, 1992$^{icg}$
* Hydraena challeti Perkins, 2011$^{icg}$
* Hydraena cheesmanae Perkins, 2011$^{icg}$
* Hydraena chenae Pu, 1951$^{icg}$
* Hydraena chersonesica Jäch, Díaz and Przewozny, 2007$^{icg}$
* Hydraena cherylbarrae Perkins, 2011$^{icg}$
* Hydraena chiapa Perkins, 1980$^{icg}$
* Hydraena chiesai Janssens, 1965$^{icg}$
* Hydraena chifengi Jäch and Díaz, 1999$^{icg}$
* Hydraena chobauti Guillebeau, 1896$^{icg}$
* Hydraena christinae Audisio, De Biase and Jäch, 1996$^{icg}$
* Hydraena christoferi Jäch and Díaz, 2005$^{icg}$
* Hydraena ciliciensis Jäch, 1988$^{icg}$
* Hydraena circulata Perkins, 1980$^{icgb}$
* Hydraena cirrata Champion, 1920$^{icg}$
* Hydraena clarinis Perkins, 2011$^{icg}$
* Hydraena claudia Freitag and Jäch, 2007$^{icg}$
* Hydraena clavicula Perkins, 2014$^{icg}$
* Hydraena clavigera Zwick, 1977$^{icg}$
* Hydraena clemens Jäch and Díaz, 2006$^{icg}$
* Hydraena clinodorsa Perkins, 2011$^{icg}$
* Hydraena clystera Perkins, 2011$^{icg}$
* Hydraena cochabamba Perkins, 2011$^{icg}$
* Hydraena colchica Janssens, 1963$^{icg}$
* Hydraena colombiana Perkins, 1980$^{icg}$
* Hydraena colorata Perkins, 2011$^{icg}$
* Hydraena colymba Perkins, 1980$^{icg}$
* Hydraena compressipilis Jäch and Díaz, 1998$^{icg}$
* Hydraena concepcionica Perkins, 2011$^{icg}$
* Hydraena concinna Orchymont, 1932$^{icg}$
* Hydraena confluenta Perkins, 2011$^{icg}$
* Hydraena confusa Pu, 1951$^{icg}$
* Hydraena connexa Orchymont, 1932$^{icg}$
* Hydraena converga Perkins, 2007$^{icg}$
* Hydraena coomani Orchymont, 1932$^{icg}$
* Hydraena cooperi Balfour-Browne, 1954$^{icg}$
* Hydraena cooperoides Perkins, 2014$^{icg}$
* Hydraena copulata Perkins, 2011$^{icg}$
* Hydraena cordata Schaufuss, 1883$^{icg}$
* Hydraena cordiformis Jäch and Díaz, 2000$^{icg}$
* Hydraena cordispina Perkins, 2011$^{icg}$
* Hydraena corinna Orchymont, 1936$^{icg}$
* Hydraena cornelli Jäch and Díaz, 1998$^{icg}$
* Hydraena corrugis Orchymont, 1934$^{icg}$
* Hydraena coryleti Jäch, 1992$^{icg}$
* Hydraena costiniceps Perkins, 1980$^{icg}$
* Hydraena crepidoptera Jäch, 1992$^{icg}$
* Hydraena cristatigena Jäch and Díaz, 2000$^{icg}$
* Hydraena croatica Kuwert, 1888$^{icg}$
* Hydraena cryptostoma Jäch, 1992$^{icg}$
* Hydraena crystallina Perkins, 1980$^{icg}$
* Hydraena cubista Perkins, 2007$^{icg}$
* Hydraena cultrata Perkins, 2007$^{icg}$
* Hydraena cunicula Perkins, 2011$^{icg}$
* Hydraena cunninghamensis Perkins, 2007$^{icg}$
* Hydraena curta Kiesenwetter, 1849$^{icg}$
* Hydraena curtipalpis Jäch and Díaz, 1998$^{icg}$
* Hydraena curvipes Jäch and Díaz, 2012$^{icg}$
* Hydraena curvosa Perkins, 2011$^{icg}$
* Hydraena cuspidicollis Perkins, 1980$^{icg}$
* Hydraena cyclops Jäch and Díaz, 2000$^{icg}$
* Hydraena cygnus Zwick, 1977$^{icg}$
* Hydraena czernohorskyi Müller, 1911$^{icg}$
* Hydraena dalmatina Ganglbauer, 1901$^{icg}$
* Hydraena damascena Pic, 1910$^{icg}$
* Hydraena dariensis Perkins, 2011$^{icg}$
* Hydraena darwini Perkins, 2007$^{icg}$
* Hydraena d-concava Perkins, 2011$^{icg}$
* Hydraena d-destina Perkins, 1980$^{icg}$
* Hydraena debeckeri (Janssens, 1972)$^{icg}$
* Hydraena decepta Perkins, 2011$^{icg}$
* Hydraena decipiens Zwick, 1977$^{icg}$
* Hydraena decolor Sainte-Claire Deville, 1903$^{icg}$
* Hydraena decui Spangler, 1980$^{icg}$
* Hydraena delia Balfour-Browne, 1978$^{icg}$
* Hydraena deliquesca Perkins, 2007$^{icg}$
* Hydraena delvasi Delgado and Collantes, 1996$^{icg}$
* Hydraena densa Fauvel, 1883$^{icg}$
* Hydraena dentipalpis Reitter, 1888$^{icg}$
* Hydraena dentipes Germar, 1824$^{icg}$
* Hydraena devillei Ganglbauer, 1901$^{icg}$
* Hydraena devincta Orchymont, 1940$^{icg}$
* Hydraena diadema Perkins, 2011$^{icg}$
* Hydraena diazi Trizzino, Jäch and Ribera in Trizzino, Jäch, Audisio and Rivera, 2011$^{icg}$
* Hydraena diffusa Perkins, 2011$^{icg}$
* Hydraena dilutipes Fairmaire, 1898$^{icg}$
* Hydraena dimorpha Orchymont, 1922$^{icg}$
* Hydraena dinosaurophila Jäch, 1994$^{icg}$
* Hydraena discicollis Fairmaire, 1898$^{icg}$
* Hydraena discreta Ganglbauer, 1904$^{icg}$
* Hydraena disparamera Perkins, 2007$^{icg}$
* Hydraena dochula Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena dolichogaster Janssens, 1965$^{icg}$
* Hydraena dorrigoensis Perkins, 2007$^{icg}$
* Hydraena draconisaurati Jäch and Díaz, 2005$^{icg}$
* Hydraena dudgeoni Perkins, 2011$^{icg}$
* Hydraena duodecimata Perkins, 2014$^{icg}$
* Hydraena duohamata Perkins, 2011$^{icg}$
* Hydraena ebriimadli Jäch, 1988$^{icg}$
* Hydraena ecuadormica Perkins, 2011$^{icg}$
* Hydraena egoni Jäch, 1986$^{icg}$
* Hydraena eichleri Orchymont, 1937$^{icg}$
* Hydraena einsteini Perkins, 2011$^{icg}$
* Hydraena elephanta Perkins, 2014$^{icg}$
* Hydraena elisabethae Jäch, 1992$^{icg}$
* Hydraena eliya Jäch, 1982$^{icg}$
* Hydraena emarginata Rey, 1885$^{icg}$
* Hydraena emineae Jäch and Kasapoglu, 2006$^{icg}$
* Hydraena epeirosi Ferro, 1985$^{icg}$
* Hydraena errina Orchymont, 1948$^{icg}$
* Hydraena erythraea Régimbart, 1905$^{icg}$
* Hydraena eryx Orchymont, 1948$^{icg}$
* Hydraena esquinita Brojer and Jäch, 2011$^{icg}$
* Hydraena essentia Perkins, 2011$^{icg}$
* Hydraena eucnemis Janssens, 1970$^{icg}$
* Hydraena evanescens Rey, 1884$^{icg}$
* Hydraena evansi Balfour-Browne, 1945$^{icg}$
* Hydraena exarata Kiesenwetter, 1866$^{icg}$
* Hydraena exasperata Orchymont, 1935$^{icg}$
* Hydraena excisa Kiesenwetter, 1849$^{icg}$
* Hydraena exhalista Perkins, 2011$^{icg}$
* Hydraena exilipes Perkins, 1980$^{icg}$
* Hydraena expedita Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena explanata Pic, 1905$^{icg}$
* Hydraena extorris Zwick, 1977$^{icg}$
* Hydraena falcata Jäch, 1992$^{icg}$
* Hydraena farsensis Skale and Jäch, 2011$^{icg}$
* Hydraena fasciata Perkins, 2011$^{icg}$
* Hydraena fascinata Perkins, 2011$^{icg}$
* Hydraena fasciola Perkins, 2011$^{icg}$
* Hydraena fasciolata Perkins, 2011$^{icg}$
* Hydraena fasciopaca Perkins, 2011$^{icg}$
* Hydraena favulosa Perkins, 2014$^{icg}$
* Hydraena fenestella Perkins, 2011$^{icg}$
* Hydraena ferethula Perkins, 2007$^{icg}$
* Hydraena feryi Skale and Jäch, 2011$^{icg}$
* Hydraena feuerborni Orchymont, 1932$^{icg}$
* Hydraena fijiensis Balfour-Browne, 1945$^{icg}$
* Hydraena filum Sahlberg, 1908$^{icg}$
* Hydraena finita Orchymont, 1943$^{icg}$
* Hydraena finki Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena finniganensis Perkins, 2007$^{icg}$
* Hydraena fiorii Porta, 1899$^{icg}$
* Hydraena fischeri Schönmann, 1991$^{icg}$
* Hydraena flagella Perkins, 2011$^{icg}$
* Hydraena fluvicola (Perkins, 1980)$^{icg}$
* Hydraena foliobba Perkins, 2011$^{icg}$
* Hydraena fontana Orchymont, 1932$^{icg}$
* Hydraena fontiscarsavii (Jäch, 1988)$^{icg}$
* Hydraena formosapala Perkins, 2011$^{icg}$
* Hydraena formula Orchymont, 1932$^{icg}$
* Hydraena forticollis Perkins, 2007$^{icg}$
* Hydraena fosterorum Trizzino, Jäch and Ribera in Trizzino, Jäch, Audisio and Rivera, 2011$^{icg}$
* Hydraena franklyni Deler-Hernández and Delgado, 2012$^{icg}$
* Hydraena freitagi Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena frenzeli Skale and Jäch, 2008$^{icg}$
* Hydraena fritzi Jäch, 1992$^{icg}$
* Hydraena frondsicola (Perkins, 1980)$^{icg}$
* Hydraena funda Perkins, 2011$^{icg}$
* Hydraena fundacta Perkins, 2011$^{icg}$
* Hydraena fundaequalis Perkins, 2007$^{icg}$
* Hydraena fundapta Perkins, 2011$^{icg}$
* Hydraena fundarca Perkins, 2011$^{icg}$
* Hydraena fundata Perkins, 2007$^{icg}$
* Hydraena fundextra Perkins, 2011$^{icg}$
* Hydraena furthi Jäch, 1982$^{icg}$
* Hydraena gaditana Lagar and Fresneda, 1990$^{icg}$
* Hydraena galatica Janssens, 1970$^{icg}$
* Hydraena galea Perkins, 2011$^{icg}$
* Hydraena gavarrensis Jäch, Díaz and Martinoy, 2005$^{icg}$
* Hydraena geminya Perkins, 1980$^{icg}$
* Hydraena genumorpha Perkins, 2014$^{icg}$
* Hydraena georgiadesi Orchymont, 1931$^{icg}$
* Hydraena geraldneuhauseri Jäch and Díaz, 2006$^{icg}$
* Hydraena germaini Orchymont, 1923$^{icg}$
* Hydraena glassmani Jäch, 1986$^{icg}$
* Hydraena gnatella Orchymont, 1945$^{icg}$
* Hydraena gnatelloides Orchymont, 1945$^{icg}$
* Hydraena gracilidelphis Trizzino, Valladares, Garrido and Audisio, 2012$^{icg}$
* Hydraena gracilis Germar, 1824$^{icg}$
* Hydraena graciloides (Jäch, 1988)$^{icg}$
* Hydraena grandis Reitter, 1885$^{icg}$
* Hydraena graphica Orchymont, 1931$^{icg}$
* Hydraena grata Orchymont, 1944$^{icg}$
* Hydraena gregalis Orchymont, 1944$^{icg}$
* Hydraena gressa Orchymont, 1944$^{icg}$
* Hydraena griphus Orchymont, 1944$^{icg}$
* Hydraena grouvellei Orchymont, 1923$^{icg}$
* Hydraena grueberi Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena guadelupensis Orchymont, 1923$^{icg}$
* Hydraena guangxiensis Jäch and Díaz, 2005$^{icg}$
* Hydraena guatemala Perkins, 1980$^{icg}$
* Hydraena guentheri Jäch, 1992$^{icg}$
* Hydraena guilin Jäch and Díaz, 2005$^{icg}$
* Hydraena gynaephila Jäch, 1997$^{icg}$
* Hydraena habitiva Perkins, 2014$^{icg}$
* Hydraena hainzi Jäch, 1988$^{icg}$
* Hydraena haitensis Perkins, 1980$^{icg}$
* Hydraena hajeki Skale and Jäch, 2011$^{icg}$
* Hydraena hamifera Zwick, 1977$^{icg}$
* Hydraena hansreuteri Jäch and Díaz, 2005$^{icg}$
* Hydraena hayashii Jäch and Díaz, 2012$^{icg}$
* Hydraena helena Orchymont, 1929$^{icg}$
* Hydraena hendrichi Jäch, Díaz and Skale, 2013$^{icg}$
* Hydraena hernandoi Fresneda and Lagar, 1990$^{icg}$
* Hydraena herzogestella Perkins, 2011$^{icg}$
* Hydraena heterogyna Bedel, 1898$^{icg}$
* Hydraena hiekei Jäch, 1992$^{icg}$
* Hydraena hillaryi Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena hintoni Perkins, 2011$^{icg}$
* Hydraena hispanica Ganglbauer, 1901$^{icg}$
* Hydraena holdhausi Pretner, 1929$^{icg}$
* Hydraena hornabrooki Perkins, 2011$^{icg}$
* Hydraena hortensis Jäch and Díaz, 2000$^{icg}$
* Hydraena hosiwergi Freitag and Jäch, 2007$^{icg}$
* Hydraena hosseinieorum Bilton and Jäch, 1998$^{icg}$
* Hydraena huangshanensis Jäch and Díaz, 2005$^{icg}$
* Hydraena huitongensis Jäch and Díaz, 2005$^{icg}$
* Hydraena humanica Perkins, 2014$^{icg}$
* Hydraena hunanensis Pu, 1951$^{icg}$
* Hydraena hungarica Rey, 1884$^{icg}$
* Hydraena huonica Perkins, 2011$^{icg}$
* Hydraena hyalina Perkins, 1980$^{icg}$
* Hydraena hynesi Zwick, 1977$^{icg}$
* Hydraena hypipamee Perkins, 2007$^{icg}$
* Hydraena ibalimi Perkins, 2011$^{icg}$
* Hydraena iberica Orchymont, 1936$^{icg}$
* Hydraena idema Perkins, 2011$^{icg}$
* Hydraena iheya Jäch and Díaz, 1999$^{icg}$
* Hydraena ilamensis Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena ilica Jäch, 1994$^{icg}$
* Hydraena imbria Jäch and Díaz, 2001$^{icg}$
* Hydraena impala Perkins, 2011$^{icg}$
* Hydraena imperatrix Kniz, 1919$^{icg}$
* Hydraena impercepta Zwick, 1977$^{icg}$
* Hydraena impressicollis Fairmaire, 1898$^{icg}$
* Hydraena inancala Perkins, 2007$^{icg}$
* Hydraena inapicipalpis Pic, 1918$^{icg}$
* Hydraena incisiva Perkins, 2011$^{icg}$
* Hydraena incista Perkins, 2011$^{icg}$
* Hydraena incurva Orchymont, 1932$^{icg}$
* Hydraena indiana Jäch, 1994$^{icg}$
* Hydraena indica Orchymont, 1920$^{icg}$
* Hydraena infoveola Perkins, 2011$^{icg}$
* Hydraena ingens (Perkins, 1980)$^{icg}$
* Hydraena inhalista Perkins, 2011$^{icg}$
* Hydraena injectiva Perkins, 2014$^{icg}$
* Hydraena innuda Perkins, 2007$^{icg}$
* Hydraena inopinata Jäch and Díaz, 1998$^{icg}$
* Hydraena inplacopaca Perkins, 2011$^{icg}$
* Hydraena insandalia Perkins, 2011$^{icg}$
* Hydraena insita Orchymont, 1932$^{icg}$
* Hydraena insolita Orchymont, 1932$^{icg}$
* Hydraena insularis Orchymont, 1945$^{icg}$
* Hydraena integra Pretner, 1931$^{icg}$
* Hydraena intensa Perkins, 2011$^{icg}$
* Hydraena intermedia Rosenhauer, 1847$^{icg}$
* Hydraena intraangulata Perkins, 2007$^{icg}$
* Hydraena inusta Orchymont, 1932$^{icg}$
* Hydraena invicta Perkins, 2007$^{icg}$
* Hydraena iriomotensis Jäch and Díaz, 1999$^{icg}$
* Hydraena isabelae Castro and Herrera, 2001$^{icg}$
* Hydraena isolinae Jäch and Díaz, 1998$^{icg}$
* Hydraena ispirensis Kasapoglu, Jäch and Skale, 2010$^{icg}$
* Hydraena iterata Orchymont, 1948$^{icg}$
* Hydraena jacobsoni Orchymont, 1932$^{icg}$
* Hydraena jaechiana (Audisio and De Biase, 1990)$^{icg}$
* Hydraena jaegeri Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena jailensis Breit, 1917$^{icg}$
* Hydraena janczyki Jäch, 1992$^{icg}$
* Hydraena janeceki Jäch, 1987$^{icg}$
* Hydraena janssensi Nilsson, 2001$^{icg}$
* Hydraena jengi Jäch and Díaz, 1998$^{icg}$
* Hydraena jilanzhui Jäch and Díaz, 2005$^{icg}$
* Hydraena jivaro Perkins, 1980$^{icg}$
* Hydraena johncoltranei Perkins, 2011$^{icg}$
* Hydraena jubilata Perkins, 2011$^{icg}$
* Hydraena kadowakii Jäch and Díaz, 2012$^{icg}$
* Hydraena kakadu Perkins, 2007$^{icg}$
* Hydraena kamitei Jäch and Díaz, 2012$^{icg}$
* Hydraena karinkukolae Jäch, 1989$^{icg}$
* Hydraena karmai Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena kasyi Jäch, 1992$^{icg}$
* Hydraena kaufmanni Ganglbauer, 1901$^{icg}$
* Hydraena kellymilleri Perkins, 2011$^{icg}$
* Hydraena khnzoriani Janssens, 1968$^{icg}$
* Hydraena kilimandjarensis Régimbart, 1906$^{icg}$
* Hydraena kitayamai Jäch and Díaz, 2012$^{icg}$
* Hydraena knischi Orchymont, 1928$^{icg}$
* Hydraena kocheri Berthélemy, 1992$^{icg}$
* Hydraena kodadai Freitag and Jäch, 2007$^{icg}$
* Hydraena koje Perkins, 2011$^{icg}$
* Hydraena koma Perkins, 2011$^{icg}$
* Hydraena krasnodarensis Jäch and Díaz, 2006$^{icg}$
* Hydraena kroumiriana Kaddouri, 1992$^{icg}$
* Hydraena kucinici Micetic Stankovic and Jäch, 2012$^{icg}$
* Hydraena kuehnelti Jäch, 1989$^{icg}$
* Hydraena kurdistanica Jäch, 1988$^{icg}$
* Hydraena kwangsiensis Pu, 1951$^{icg}$
* Hydraena labropaca Perkins, 2011$^{icg}$
* Hydraena lagamba Brojer and Jäch, 2011$^{icg}$
* Hydraena lapidicola Kiesenwetter, 1849$^{icg}$
* Hydraena lapissectilis Jäch, 1992$^{icg}$
* Hydraena larissae Jäch and Díaz, 2000$^{icg}$
* Hydraena larsoni Perkins, 2007$^{icg}$
* Hydraena lascrucensis Brojer and Jäch, 2011$^{icg}$
* Hydraena lassulipes Perkins, 2011$^{icg}$
* Hydraena latebricola Jäch, 1986$^{icg}$
* Hydraena latisoror Perkins, 2007$^{icg}$
* Hydraena lazica Janssens, 1963$^{icg}$
* Hydraena leechi Perkins, 1980$^{icg}$
* Hydraena leei Jäch and Díaz, 1998$^{icg}$
* Hydraena legorskyi Jäch and Brojer, 2012$^{icg}$
* Hydraena lehmanni Jäch and Díaz, 2005$^{icg}$
* Hydraena leonhardi Breit, 1916$^{icg}$
* Hydraena leprieuri Sainte-Claire Deville, 1905$^{icg}$
* Hydraena levantina Sahlberg, 1908$^{icg}$
* Hydraena ligulipes Jäch, 1988$^{icg}$
* Hydraena lilianae Perkins, 2011$^{icg}$
* Hydraena limbobesa Perkins, 2011$^{icg}$
* Hydraena limpidicollis Perkins, 1980$^{icg}$
* Hydraena liriope Orchymont, 1943$^{icg}$
* Hydraena longicollis Sharp, 1882$^{icg}$
* Hydraena loripes Perkins, 2011$^{icg}$
* Hydraena lotti Bilton, 2013$^{icg}$
* Hydraena lucasi Lagar, 1984$^{icg}$
* Hydraena lucernae Zwick, 1977$^{icg}$
* Hydraena ludovicae Orchymont, 1931$^{icg}$
* Hydraena luminicollis Perkins, 2007$^{icg}$
* Hydraena luridipennis MacLeay, 1873$^{icg}$
* Hydraena lusitana (Berthélemy in Berthélemy and Whytton Da Terra, 1977)$^{icg}$
* Hydraena lycia Jäch, 1988$^{icg}$
* Hydraena macedonica Orchymont, 1931$^{icg}$
* Hydraena maculicollis Champion, 1920$^{icg}$
* Hydraena maculopala Perkins, 2011$^{icg}$
* Hydraena madronensis Castor, García and Ferreras, 2000$^{icg}$
* Hydraena magna Pu, 1951$^{icg}$
* Hydraena magnessa Jäch, 1997$^{icg}$
* Hydraena magnetica Zwick, 1977$^{icg}$
* Hydraena mahensis Scott, 1913$^{icg}$
* Hydraena malagricola Jäch and Díaz, 2012$^{icg}$
* Hydraena malickyi Jäch, 1989$^{icg}$
* Hydraena malkini Perkins, 1980$^{icg}$
* Hydraena manabica Perkins, 2011$^{icg}$
* Hydraena manaslu Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena manfredjaechi Delgado and Soler, 1991$^{icg}$
* Hydraena manguao Freitag and Jäch, 2007$^{icg}$
* Hydraena manulea Perkins, 2011$^{icg}$
* Hydraena manuloides Perkins, 2011$^{icg}$
* Hydraena marawaka Perkins, 2011$^{icg}$
* Hydraena marcosae Aguilera, Hernando and Ribera, 1997$^{icg}$
* Hydraena marginicollis Kiesenwetter, 1849$^{icg}$
* Hydraena mariannae Jäch, 1992$^{icg}$
* Hydraena marinae Castro, 2003$^{icg}$
* Hydraena martensi Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena martinschoepfi Jäch and Díaz, 2005$^{icg}$
* Hydraena masatakai Jäch and Díaz, 2003$^{icg}$
* Hydraena maureenae Perkins, 1980$^{icg}$
* Hydraena mauriciogarciai Perkins, 2011$^{icg}$
* Hydraena mazamitla Perkins, 1980$^{icg}$
* Hydraena mecai Millán and Aguilera, 2000$^{icg}$
* Hydraena melas Dalla Torre, 1877$^{icg}$
* Hydraena mercuriala Perkins, 2011$^{icg}$
* Hydraena meschniggi Pretner, 1929$^{icg}$
* Hydraena metzeni Perkins, 2007$^{icg}$
* Hydraena mexicana Perkins, 1980$^{icg}$
* Hydraena mianminica Perkins, 2011$^{icg}$
* Hydraena michaelbalkei Jäch, Díaz and Skale, 2013$^{icg}$
* Hydraena mignymixys Perkins, 1980$^{icg}$
* Hydraena millerorum Perkins, 2007$^{icg}$
* Hydraena miniretia Perkins, 2007$^{icg}$
* Hydraena mintrita Perkins, 2011$^{icg}$
* Hydraena mitchellensis Perkins, 2007$^{icg}$
* Hydraena miyatakei Satô, 1959$^{icg}$
* Hydraena modili Jäch, 1988$^{icg}$
* Hydraena monikae Jäch and Díaz, 2000$^{icg}$
* Hydraena monscassius Jäch, 1988$^{icg}$
* Hydraena monstruosipes Ferro, 1986$^{icg}$
* Hydraena monteithi Perkins, 2007$^{icg}$
* Hydraena morio Kiesenwetter, 1849$^{icg}$
* Hydraena motzfeldi Skale and Jäch, 2011$^{icg}$
* Hydraena mouzaiensis Sainte-Claire Deville, 1909$^{icg}$
* Hydraena mpumalanga Perkins, 2014$^{icg}$
* Hydraena muelleri Pretner, 1931$^{icg}$
* Hydraena muezziginea Jäch, 1988$^{icg}$
* Hydraena multiloba Perkins, 2011$^{icg}$
* Hydraena multimurata Perkins, 2014$^{icg}$
* Hydraena multispina Perkins, 2011$^{icg}$
* Hydraena mylasae Jäch, 1992$^{icg}$
* Hydraena namibiensis Perkins, 2014$^{icg}$
* Hydraena nanocolorata Perkins, 2011$^{icg}$
* Hydraena nanopala Perkins, 2011$^{icg}$
* Hydraena nanoscintilla Perkins, 2011$^{icg}$
* Hydraena natiforma Perkins, 2014$^{icg}$
* Hydraena neblina Perkins, 2011$^{icg}$
* Hydraena nelsonmandelai Makhan, 2008$^{icg}$
* Hydraena neoaccurata Perkins, 2014$^{icg}$
* Hydraena nevermanni Perkins, 1980$^{icg}$
* Hydraena newtoni Perkins, 1980$^{icg}$
* Hydraena nielshaggei Freitag and Jäch, 2007$^{icg}$
* Hydraena nigra Hatch, 1965$^{icg}$
* Hydraena nigrita Germar, 1824$^{icg}$
* Hydraena nike Jäch, 1995$^{icg}$
* Hydraena nilguenae (Jäch, 1988)$^{icg}$
* Hydraena nitidimenta Perkins, 2011$^{icg}$
* Hydraena nivalis Jäch, 1992$^{icg}$
* Hydraena nomenipes Perkins, 2014$^{icg}$
* Hydraena notsui Satô, 1978$^{icg}$
* Hydraena novacula Perkins, 2011$^{icg}$
* Hydraena numidica Sainte-Claire Deville, 1905$^{icg}$
* Hydraena nurabadensis Skale and Jäch, 2011$^{icg}$
* Hydraena nuratauensis Jäch, 1994$^{icg}$
* Hydraena oaxaca Perkins, 1980$^{icg}$
* Hydraena oblio Perkins, 1980$^{icg}$
* Hydraena occidentalis Perkins, 1980$^{icg}$
* Hydraena occitana (Audisio and De Biase, 1995)$^{icg}$
* Hydraena okapa Perkins, 2011$^{icg}$
* Hydraena okinawensis Jäch and Díaz, 1999$^{icg}$
* Hydraena olidipastoris Jäch, 1988$^{icg}$
* Hydraena ollopa Perkins, 2011$^{icg}$
* Hydraena optica Jäch and Díaz, 2012$^{icg}$
* Hydraena orchis Jäch and Díaz, 1998$^{icg}$
* Hydraena orcula Perkins, 1980$^{icg}$
* Hydraena ordishi Delgado and Palma, 1997$^{icg}$
* Hydraena orientalis Breit, 1916$^{icg}$
* Hydraena ortali Jäch, 1986$^{icg}$
* Hydraena orthosia Jäch, Díaz and Dia in Jäch, Dia and Díaz, 2006$^{icg}$
* Hydraena otiarca Perkins, 2011$^{icg}$
* Hydraena ovata Janssens, 1961$^{icg}$
* Hydraena owenobesa Perkins, 2011$^{icg}$
* Hydraena oxiana Janssens, 1974$^{icg}$
* Hydraena ozarkensis Perkins, 1980$^{icg}$
* Hydraena pachyptera Apfelbeck, 1909$^{icg}$
* Hydraena pacifica Perkins, 1980$^{icg}$
* Hydraena pacificica Perkins, 2011$^{icg}$
* Hydraena paeminosa Perkins, 1980$^{icg}$
* Hydraena pagaluensis Hernando and Ribera, 2001$^{icg}$
* Hydraena paganettii Ganglbauer, 1901$^{icg}$
* Hydraena pajarita Brojer and Jäch, 2011$^{icg}$
* Hydraena pakistanica Jäch, 1992$^{icg}$
* Hydraena pala Perkins, 2011$^{icg}$
* Hydraena palamita Perkins, 2011$^{icg}$
* Hydraena palawanensis Freitag and Jäch, 2007$^{icg}$
* Hydraena pallidula Sainte-Claire Deville, 1909$^{icg}$
* Hydraena palustris Erichson, 1837$^{icg}$
* Hydraena pamirica Jäch, 1992$^{icg}$
* Hydraena pamphylia Jäch and Díaz, 2001$^{icg}$
* Hydraena pangaei Jäch, 1992$^{icg}$
* Hydraena pantanalensis Perkins, 2011$^{icg}$
* Hydraena paraguayensis Janssens, 1972$^{icg}$
* Hydraena parciplumea Perkins, 2007$^{icg}$
* Hydraena particeps Perkins, 1980$^{icg}$
* Hydraena parva Zwick, 1977$^{icg}$
* Hydraena parysatis Janssens, 1981$^{icg}$
* Hydraena paucistriata Jäch and Díaz, 2000$^{icg}$
* Hydraena paulmoritz Jäch, Díaz and Skale, 2013$^{icg}$
* Hydraena pavicula Perkins, 1980$^{icg}$
* Hydraena paxillipes Perkins, 2011$^{icg}$
* Hydraena peckorum Perkins, 2011$^{icg}$
* Hydraena pectenata Perkins, 2011$^{icg}$
* Hydraena pedroaguilerai Perkins, 2011$^{icg}$
* Hydraena pegopyga Perkins, 2011$^{icg}$
* Hydraena pelops Jäch, 1995$^{icg}$
* Hydraena pennsylvanica Kiesenwetter, 1849$^b$
* Hydraena pensylvanica Kiesenwetter, 1849$^{icg}$
* Hydraena penultimata Perkins, 2011$^{icg}$
* Hydraena perkinsi Spangler, 1980$^{icg}$
* Hydraena perlonga Balfour-Browne, 1950$^{icg}$
* Hydraena perpunctata Perkins, 2011$^{icg}$
* Hydraena persica Janssens, 1981$^{icg}$
* Hydraena pertransversa Perkins, 2011$^{icg}$
* Hydraena peru Perkins, 1980$^{icg}$
* Hydraena pesici Skale and Jäch, 2011$^{icg}$
* Hydraena petila Perkins, 1980$^{icg}$
* Hydraena phainops Perkins, 2011$^{icg}$
* Hydraena phallerata Orchymont, 1944$^{icg}$
* Hydraena phallica Orchymont, 1930$^{icg}$
* Hydraena phassilyi Orchymont, 1931$^{icg}$
* Hydraena philippi Jäch and Díaz, 2005$^{icg}$
* Hydraena philyra Orchymont, 1944$^{icg}$
* Hydraena phoenicia Jäch, Díaz and Dia in Jäch, Dia and Díaz, 2006$^{icg}$
* Hydraena photogenica Perkins, 2011$^{icg}$
* Hydraena pici Sainte-Claire Deville, 1905$^{icg}$
* Hydraena picula Perkins, 2011$^{icg}$
* Hydraena pilimera Brojer and Jäch, 2011$^{icg}$
* Hydraena pilipes Zwick, 1977$^{icg}$
* Hydraena pilulambra Perkins, 2011$^{icg}$
* Hydraena pindica Janssens, 1965$^{icg}$
* Hydraena pisciforma Perkins, 2014$^{icg}$
* Hydraena planata Kiesenwetter, 1849$^{icg}$
* Hydraena plastica Orchymont, 1943$^{icg}$
* Hydraena platycnemis Jäch, 1988$^{icg}$
* Hydraena platynaspis Jäch, 1988$^{icg}$
* Hydraena platysoma Janssens, 1968$^{icg}$
* Hydraena plaumanni Orchymont, 1937$^{icg}$
* Hydraena plumipes Rey, 1886$^{icg}$
* Hydraena pluralticola Perkins, 2011$^{icg}$
* Hydraena plurifurcata Jäch and Díaz, 1998$^{icg}$
* Hydraena polita Kiesenwetter, 1849$^{icg}$
* Hydraena pontequula Perkins, 1980$^{icg}$
* Hydraena pontica Janssens, 1963$^{icg}$
* Hydraena porchi Perkins, 2007$^{icg}$
* Hydraena porcula Jäch and Díaz, 1998$^{icg}$
* Hydraena praetermissa Jäch, 1987$^{icg}$
* Hydraena premordica Perkins, 1980$^{icg}$
* Hydraena pretneri Chiesa, 1927$^{icg}$
* Hydraena prieto Perkins, 1980$^{icg}$
* Hydraena princeps Fauvel, 1903$^{icg}$
* Hydraena processa Perkins, 2011$^{icg}$
* Hydraena producta Mulsant and Rey, 1852$^{icg}$
* Hydraena proesei Skale and Jäch, 2011$^{icg}$
* Hydraena profunda Perkins, 2014$^{icg}$
* Hydraena prokini Jäch and Díaz, 2006$^{icg}$
* Hydraena propria Perkins, 2011$^{icg}$
* Hydraena prusensis Jäch, 1992$^{icg}$
* Hydraena pseudocirrata Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena pseudopalawanensis Freitag and Jäch, 2007$^{icg}$
* Hydraena pseudoriparia Orchymont, 1945$^{icg}$
* Hydraena puetzi Jäch, 1994$^{icg}$
* Hydraena pugillista Perkins, 2007$^{icg}$
* Hydraena pulchella Germar, 1824$^{icg}$
* Hydraena pulsatrix Perkins, 1980$^{icg}$
* Hydraena punctata LeConte, 1855$^{icg}$
* Hydraena puncticollis Sharp, 1882$^{icg}$
* Hydraena punctilata Perkins, 2011$^{icg}$
* Hydraena putearius Jäch and Díaz, 2000$^{icg}$
* Hydraena pygmaea Waterhouse, 1833$^{icg}$
* Hydraena quadrata (Janssens, 1980)$^{icg}$
* Hydraena quadricollis Wollaston, 1864$^{icg}$
* Hydraena quadricurvipes Perkins, 1980$^{icg}$
* Hydraena quadriplumipes Perkins, 2011$^{icg}$
* Hydraena quechua Perkins, 1980$^{icg}$
* Hydraena queenslandica Perkins, 2007$^{icg}$
* Hydraena quetiae Castro, 2000$^{icg}$
* Hydraena quilisi Lagar, Fresneda and Fernando, 1987$^{icg}$
* Hydraena quintana Perkins, 2011$^{icg}$
* Hydraena ramuensis Perkins, 2011$^{icg}$
* Hydraena ramuquintana Perez, 2011$^{icg}$
* Hydraena receptiva Perkins, 2011$^{icg}$
* Hydraena reflectiva Perkins, 2014$^{icg}$
* Hydraena regimbarti Zaitzev, 1908$^{icg}$
* Hydraena remulipes Perkins, 2011$^{icg}$
* Hydraena reticulata Zwick, 1977$^{icg}$
* Hydraena reticuloides Perkins, 2007$^{icg}$
* Hydraena reticulositis Perkins, 2007$^{icg}$
* Hydraena revelovela Perkins, 2007$^{icg}$
* Hydraena reverberata Perkins, 2011$^{icg}$
* Hydraena reyi Kuwert, 1888$^{icg}$
* Hydraena rhinoceros (Janssens, 1972)$^{icg}$
* Hydraena rhodia Jäch, 1985$^{icg}$
* Hydraena riberai Jäch, Aguilera and Hernando, 1998$^{icg}$
* Hydraena richardimbi Jäch, 1992$^{icg}$
* Hydraena rigua Orchymont, 1931$^{icg}$
* Hydraena ripaeaureae (Janssens, 1972)$^{icg}$
* Hydraena riparia Kugelann, 1794$^{icg}$
* Hydraena rivularis Guillebeau, 1896$^{icg}$
* Hydraena robusta Zwick, 1977$^{icg}$
* Hydraena rosannae Audisio, Trizzino and De Biase in Audisio, Trizzino, De Biase, Mancini and Antonini, 2009$^{icg}$
* Hydraena rudallensis Blackburn, 1896$^{icg}$
* Hydraena rufipennis Boscá Berga, 1932$^{icg}$
* Hydraena rufipes Curtis, 1830$^{icg}$
* Hydraena rugosa Mulsant, 1844$^{icg}$
* Hydraena ruinosa Zwick, 1977$^{icg}$
* Hydraena rukiyeae Kasapoglu, Jäch and Skale, 2010$^{icg}$
* Hydraena sabella Perkins, 1980$^{icg}$
* Hydraena saga Orchymont, 1930$^{icg}$
* Hydraena sagatai Perkins, 2011$^{icg}$
* Hydraena sahlbergi Orchymont, 1923$^{icg}$
* Hydraena saluta Perkins, 2011$^{icg}$
* Hydraena samia Jäch, 1986$^{icg}$
* Hydraena samnitica Knisch, 1924$^{icg}$
* Hydraena sanagergelyae Brojer and Jäch, 2011$^{icg}$
* Hydraena sanfilippoi (Audisio and De Biase, 1995)$^{icg}$
* Hydraena sappho Janssens, 1965$^{icg}$
* Hydraena sardoa Binaghi, 1961$^{icg}$
* Hydraena satoi Jäch and Díaz, 1999$^{icg}$
* Hydraena sautakei Jäch and Díaz, 1999$^{icg}$
* Hydraena sauteri Orchymont, 1913$^{icg}$
* Hydraena scabra Orchymont, 1925$^{icg}$
* Hydraena scabrosa Orchymont, 1931$^{icg}$
* Hydraena schawalleri Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena schilfii Jäch, 1988$^{icg}$
* Hydraena schillhammeri Jäch, 1988$^{icg}$
* Hydraena schmidi Jäch and Díaz, 2001$^{icg}$
* Hydraena schoedli Jäch, 1992$^{icg}$
* Hydraena schoenmanni Jäch, 1988$^{icg}$
* Hydraena schubertorum Jäch and Díaz, 2001$^{icg}$
* Hydraena schuelkei Jäch, 1992$^{icg}$
* Hydraena schuleri Ganglbauer, 1901$^{icg}$
* Hydraena scintilla Perkins, 1980$^{icg}$
* Hydraena scintillabella Perkins, 1980$^{icg}$
* Hydraena scintillamima Perkins, 2011$^{icg}$
* Hydraena scintillapicta Perkins, 2011$^{icg}$
* Hydraena scintillarca Perkins, 2011$^{icg}$
* Hydraena scintillutea Perkins, 1980$^{icg}$
* Hydraena scitula Orchymont, 1943$^{icg}$
* Hydraena scolops Perkins, 1980$^{icg}$
* Hydraena scopula Perkins, 1980$^{icg}$
* Hydraena scythica Janssens, 1974$^{icg}$
* Hydraena sebastiani Perkins, 2014$^{icg}$
* Hydraena sepikramuensis Perkins, 2011$^{icg}$
* Hydraena septemlacuum Jäch, 1992$^{icg}$
* Hydraena serpentina Jäch, 1988$^{icg}$
* Hydraena serricollis Wollaston, 1864$^{icg}$
* Hydraena servilia Orchymont, 1936$^{icg}$
* Hydraena sexarcuata Perkins, 2011$^{icg}$
* Hydraena sexsuprema Perkins, 2011$^{icg}$
* Hydraena sharmai Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena sharpi Rey, 1886$^{icg}$
* Hydraena shorti Perkins, 2011$^{icg}$
* Hydraena sicula Kiesenwetter, 1849$^{icg}$
* Hydraena sidon Jäch, Díaz and Dia in Jäch, Dia and Díaz, 2006$^{icg}$
* Hydraena sierra Perkins, 1980$^{icg}$
* Hydraena similis Orchymont, 1930$^{icg}$
* Hydraena simonidea Orchymont, 1931$^{icg}$
* Hydraena simplicicollis Blackburn, 1896$^{icg}$
* Hydraena simplipes Zwick, 1977$^{icg}$
* Hydraena singaporensis Jäch, Díaz and Skale, 2013$^{icg}$
* Hydraena sinope Jäch, 1992$^{icg}$
* Hydraena smyrnensis Sahlberg, 1908$^{icg}$
* Hydraena socius Jäch and Díaz, 1999$^{icg}$
* Hydraena solarii Pretner, 1930$^{icg}$
* Hydraena solodovnikovi Jäch and Díaz, 2006$^{icg}$
* Hydraena sordida Sharp, 1882$^{icg}$
* Hydraena spangleri Perkins, 1980$^{icg}$
* Hydraena spatula Perkins, 2011$^{icg}$
* Hydraena speciosa Orchymont, 1944$^{icg}$
* Hydraena spinipes Baudi, 1882$^{icg}$
* Hydraena spinissima Perkins, 2007$^{icg}$
* Hydraena spinobesa Perkins, 2011$^{icg}$
* Hydraena splecoma Perkins, 1980$^{icg}$
* Hydraena squalida Orchymont, 1932$^{icg}$
* Hydraena stefani Jäch and Díaz, 2005$^{icg}$
* Hydraena steineri Perkins, 2011$^{icg}$
* Hydraena stellula Perkins, 2011$^{icg}$
* Hydraena storeyi Perkins, 2007$^{icg}$
* Hydraena striolata Perkins, 2011$^{icg}$
* Hydraena stussineri Kuwert, 1888$^{icg}$
* Hydraena subacuminata Rey, 1884$^{icg}$
* Hydraena subgrandis Jäch, 1988$^{icg}$
* Hydraena subimpressa Rey, 1885$^{icg}$
* Hydraena subina Orchymont, 1944$^{icg}$
* Hydraena subinflata Orchymont, 1944$^{icg}$
* Hydraena subinoides Orchymont, 1944$^{icg}$
* Hydraena subintegra Ganglbauer, 1901$^{icg}$
* Hydraena subinura Orchymont, 1944$^{icg}$
* Hydraena subirregularis Pic, 1918$^{icg}$
* Hydraena subjuncta Orchymont, 1930$^{icg}$
* Hydraena sublamina Orchymont, 1945$^{icg}$
* Hydraena sublapsa Orchymont, 1945$^{icg}$
* Hydraena subsequens Rey, 1886$^{icg}$
* Hydraena supersexa Perkins, 2011$^{icg}$
* Hydraena supina Perkins, 2011$^{icg}$
* Hydraena szechuanensis Pu, 1951$^{icg}$
* Hydraena takin Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena takutu Perkins, 2011$^{icg}$
* Hydraena tarsotricha Perkins, 2011$^{icg}$
* Hydraena tarvisina (Ferro, 1992)$^{icg}$
* Hydraena tatii Sáinz-Cantero and Alba-Tercedor, 1989$^{icg}$
* Hydraena tauricola Jäch, 1988$^{icg}$
* Hydraena taxila Janssens, 1962$^{icg}$
* Hydraena tekmanensis Jäch, Skale and Kasapoglu, 2011$^{icg}$
* Hydraena tenjikuana Satô, 1979$^{icg}$
* Hydraena tenuis (Janssens, 1980)$^{icg}$
* Hydraena tenuisella Perkins, 2007$^{icg}$
* Hydraena tenuisoror Perkins, 2007$^{icg}$
* Hydraena terebrans Jäch, 1992$^{icg}$
* Hydraena terralta Perkins, 1980$^{icg}$
* Hydraena testacea Curtis, 1830$^{icg}$
* Hydraena tetana Perkins, 2011$^{icg}$
* Hydraena textila Perkins, 2007$^{icg}$
* Hydraena thienemanni Orchymont, 1932$^{icg}$
* Hydraena thola Perkins, 2011$^{icg}$
* Hydraena tholasoris Perkins, 2011$^{icg}$
* Hydraena thumbelina Perkins, 2011$^{icg}$
* Hydraena thumbelipes Perkins, 2011$^{icg}$
* Hydraena thyene Balfour-Browne, 1958$^{icg}$
* Hydraena tiara Perkins, 2014$^{icg}$
* Hydraena tibiopaca Perkins, 2011$^{icg}$
* Hydraena tobogan Perkins, 2011$^{icg}$
* Hydraena torosopala Perkins, 2011$^{icg}$
* Hydraena torricellica Perkins, 2011$^{icg}$
* Hydraena transvallis Perkins, 2011$^{icg}$
* Hydraena trapezoidalis Zwick, 1977$^{icg}$
* Hydraena tricantha Zwick, 1977$^{icg}$
* Hydraena trichotarsa Perkins, 2011$^{icg}$
* Hydraena tricosipes Perkins, 2011$^{icg}$
* Hydraena tridigita Perkins, 2011$^{icg}$
* Hydraena tridisca Perkins, 2007$^{icg}$
* Hydraena triloba Perkins, 2007$^{icg}$
* Hydraena trinidensis Perkins, 1980$^{icg}$
* Hydraena triparamera Jäch, 1982$^{icg}$
* Hydraena tritropis Perkins, 2011$^{icg}$
* Hydraena tritutela Perkins, 2011$^{icg}$
* Hydraena truncata Rey, 1885$^{icg}$
* Hydraena tsushimaensis Jäch and Díaz, 2012$^{icg}$
* Hydraena tubuliphallis Jäch, 1982$^{icg}$
* Hydraena tucumanica Perkins, 1980$^{icg}$
* Hydraena tuolumne Perkins, 1980$^{icg}$
* Hydraena turcica Janssens, 1965$^{icg}$
* Hydraena turrialba Perkins, 1980$^{icg}$
* Hydraena tyrrhena Binaghi, 1961$^{icg}$
* Hydraena ulna Perkins, 2011$^{icg}$
* Hydraena umbolenta Perkins, 2011$^{icg}$
* Hydraena unca Valladares, 1989$^{icg}$
* Hydraena undevigintioctogintasisyphos Jäch and Díaz, 2005$^{icg}$
* Hydraena undulata Jäch and Díaz, 1998$^{icg}$
* Hydraena uniforma Perkins, 2014$^{icg}$
* Hydraena unita Perkins, 2011$^{icg}$
* Hydraena uzbekistanica Jäch, 1994$^{icg}$
* Hydraena vadosa Perkins, 2014$^{icg}$
* Hydraena valentini Jäch and Díaz, 2012$^{icg}$
* Hydraena vandykei Orchymont, 1923$^{icg}$
* Hydraena variopaca Perkins, 2011$^{icg}$
* Hydraena vedrasi Orchymont, 1931$^{icg}$
* Hydraena vela Perkins, 1980$^{icg}$
* Hydraena velvetina Perkins, 2011$^{icg}$
* Hydraena venezuela Perkins, 2011$^{icg}$
* Hydraena verberans Jäch and Díaz, 2006$^{icg}$
* Hydraena verstraeteni Ferro, 1984$^{icg}$
* Hydraena victoriae Jäch and Díaz, 1999$^{icg}$
* Hydraena vietnamensis (Janssens, 1972)$^{icg}$
* Hydraena virginalis Janssens, 1963$^{icg}$
* Hydraena vodozi Sainte-Claire Deville, 1908$^{icg}$
* Hydraena vulgaris Jäch and Díaz, 2000$^{icg}$
* Hydraena waldheimi Jäch, 1987$^{icg}$
* Hydraena wangi Jäch and Díaz, 1998$^{icg}$
* Hydraena wangmiaoi Jäch and Díaz, 2005$^{icg}$
* Hydraena watanabei Jäch and Satô, 1988$^{icg}$
* Hydraena wattsi Perkins, 2007$^{icg}$
* Hydraena weigeli Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena weiri Perkins, 2007$^{icg}$
* Hydraena wencke Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena wewalkai Jäch, 1988$^{icg}$
* Hydraena williamsensis Deane, 1931$^{icg}$
* Hydraena wittmeri Satô, 1979$^{icg}$
* Hydraena wolfi Skale and Jäch in Jäch and Skale, 2009$^{icg}$
* Hydraena wrasei Jäch, 1992$^{icg}$
* Hydraena xingu Perkins, 2011$^{icg}$
* Hydraena yangae Jäch, Díaz and Skale, 2013$^{icg}$
* Hydraena yonaguniensis Jäch and Díaz, 2003$^{icg}$
* Hydraena yosemitensis Perkins, 1980$^{icg}$
* Hydraena yoshitomii Jäch and Díaz, 1999$^{icg}$
* Hydraena youngi Perkins, 1980$^{icg}$
* Hydraena ypsilon Zwick, 1977$^{icg}$
* Hydraena yunnanensis Pu, 1942$^{icg}$
* Hydraena zapatina Perkins, 1980$^{icg}$
* Hydraena zelandica Ordish, 1984$^{icg}$
* Hydraena zetteli Freitag and Jäch, 2007$^{icg}$
* Hydraena zezerensis Díaz Pazos and Bilton, 1995$^{icg}$
* Hydraena zimbabwensis Perkins, 2014$^{icg}$
* Hydraena zwicki Perkins, 2007$^{icg}$
Data sources: i = ITIS, c = Catalogue of Life, g = GBIF, b = Bugguide.net