Genus Chaetocladius Research Articles

Chaetocladius berythensis sp. n., C. callauensis sp. n., C. guardiolei sp. n. and C. parerai sp. n., four relict species inhabiting glacial springs and streams in eastern Pyrenees and Lebanon (Diptera: Chironomidae)

Four new species of the genus Chaetocladius s. str. (C. berythensis sp. n., C. callauensis sp. n., C. guardiolei sp. n. and C. parerai sp. n.) are diagnosed and described based on material collected in some glacial springs and small streams located at high altitude (1800-2300 m). While C. berythensis sp. n. is described only as male adult from the upper basin of the Beirut River (Lebanon Mount, Western range, Mount Sannine), C. callauensis sp. n. C. guardiolei sp. n. and C. parerai sp. n. are described as male adult accompanied by descriptions of tentatively associated male pupal exuviae from the upper basin of the Mantet River and Soques stream (eastern Pyrenees, West France). Additional taxonomic notes including illustrations and brief descriptions of 10 taxa/species based on male adults, male pharate adults and pupal exuviae collected in glacial springs, peat bogs and streams located at high altitude are provided. On the basis of characters in the male adult, only C. berythensis sp. n. keys to the laminatus-group, which is reported for the first time from the Levantine sub-region. Based on the unusual shape of both inferior volsella and gonostylus, the four new Chaetocladius species each belong to local biogeographic elements: C. berythensis sp. n. to a ‘Levantine element’, while C. callauensis sp. n., C. guardiolei sp. n. and C. parerai sp. n. belong to a ‘Pyrenean element’. All of the four new species are considered to be relict representatives of glacial helocrenes and cold stenothermic streams. Such species may be biological indicators and biogeographic representatives of global warming and local climate change.

Taxonomic notes on the genus Chaetocladius (laminatus-group) (Diptera: Chironomidae, Orthocladiinae) II. Descriptions of C. bitusiki sp. n. and C. mantetensis sp. n., two relict species inhabiting cold alpine springs and streams

Two new species of the genus Chaetocladius s. str. (C. bitusiki sp. n. and C. mantetensis sp. n.) are diagnosed and described based on material collected in some cold springs and small streams located at high altitude (1940–2300 m) in the High Tatra Mountains (Slovakia) and Eastern Pyrenees (France). The first one is described as male adult and pupal exuviae, while the second is described as male and female adults and pupal exuviae. Both C. bitusiki sp. n. and C. mantetensis sp. n. key to the laminatus-group for known Chaetocladius species on the basis of some characters found in the male adult: virga composed of three typical parts, inferior volsella sub-triangular to sub-circular, narrow to broad lobe, bearing or lacking a posterior marsupial-like pouch and an apical contrasting protuberance; gonostylus triangular, projecting posteriorly as a pointed or rounded apex. Taxonomic remarks on related Chaetocladius species, key to known male adults of the laminatus-group from Europe with comments on the ecology and geographical distribution of the new species are given. The two new species can be regarded as typical relict representatives of cold springs and streams at high altitudes. Such species could be used as relevant biological indicators of the global warming and local climate change.

On the genus Chaetocladius s. str. Kieffer, 1911 from Switzerland with descriptions of five new relic species occurring in glacial alpine springs and streams (Diptera, Chironomidae)

A description of the male adults of fiveChaetocladiuss. str. species (C. castellaesp. n.,C. lencioniaesp. n.,C. lodscrozetaesp. n.,C. macunensissp. n. andC. muttensissp. n.) is provided based on material collected in some glacial alpine springs and cold streams located in the Swiss Alps (altitude 1800–2700 m). Male adult of the nearestChaetocladiusspecies known from Europe and neighbouring areas belong to:C. aedeagolobatusRossaro, Magoga & Montagna, 2017;C. insolitusCaspers, 1987;C. gracilisBrundin 1956;C. antipovaeMakarchenko & Makarchenko, 2011;C. dissipatus(Edwards, 1929),C. holmgreni(Jacobson, 1998),C. egorychMakarchenko & Makarchenko, 2017. Although some resemblance can be found between the five diagnosed and described species and other related members of theChaetocladiusgenus, the taxonomic position cannot be clarified until current comprehensive work on the genus is complete. Geographical distribution of the five new species is currently restricted to the two Alpine Swiss glacial catchments: upper basins of the Rhône River and Muttbach streams; streams and lakes delimited by the Macun area. This highlights the importance of some high mountain ranges, considered as cold glacial enclaves and hotspots of endemism, in the preservation and persistence of autochthonous alpine relic species. Such species are considered as relevant biogeographic representative and their loss would be biologically indicative of global warming and climate change. Currently, there are only seven recordedChaetocladiusspecies from Switzerland:C. coppaiMoubayed-Breil, 2017;C. laminatusBrundin, 1947; C. cf. longivirgatus Stur & Spies, 2011;C. melaleucus(Meigen, 1818);C. perennis(Meigen, 1830);C. piger(Goetghebuer, 1913);C. suecicus(Kieffer, 1916). Consequently, the description of the five new species increases the total number in the genusChaetocladiusto twelve for this country. Remarks and comments on the taxonomic position, ecology and geographical distribution of the new described species, with key to known male adults from the upper catchment of Rhône River (including Muttbach valley) are provided..

Chaetocladius coppai sp. nov. and C. diai sp. nov., two mountain species inhabiting glacial springs and cold streams of the Alps and Lebanon (Diptera: Chironomidae, Orthocladiinae)

Two new species of the genus Chaetocladius are described, C. (s. str.) coppai sp. nov. as male adult and C. (s. str.) diai sp. nov. as male adult and pupa. The descriptions are based on the material collected at glacial alpine springs and small streams located in the Maritime French Alps and the Swiss Alps for C. coppai sp. nov., and the Mount Lebanon range for C. diai sp. nov. According to the characters of the adult males, C. coppai sp. nov. belongs to the laminatus-group, while C. diai sp. nov. is close to C. elegans Makarchenko et Makarchenko, 2001. The comments on the taxonomic position, ecology and geographical distribution of the new species are given.

Revision of the genus Chaetocladius Kieffer (Diptera, Chironomidae), 1st note: description of four new species from Italy

Four new species belonging to the genus Chaetocladius, known to occur in Italy, are here described as adult males: C. aedeagovirgatus sp. nov., C. subalpinus sp. nov., C. ticinoi sp. nov., and C. valdostanus sp. nov. C. aedeagolobatus is characterized by a robust aedeagal lobe, C. subalpinus and C. valdostanus by a characteristic inferior volsella, C. ticinoi by a tubercle on the basis of gonostylus. Geographical distribution of the other species known to occur in Italy is given. A key to adult males is presented.

A review of Norwegian Gymnometriocnemus (Diptera, Chironomidae) including the description of two new species and a new name for Gymnometriocnemusvolitans (Goetghebuer) sensu Brundin.

Examination of the syntypes of Metriocnemus volitans Goetghebuer, 1940 revealed that these specimens belong to the genus Chaetocladius and are not con-specific with Gymnometriocnemus volitans (Goetghebuer, 1940) sensu Brundin (1956) and Sæther (1983). A literature search showed that Gymnometriocnemus kamimegavirgus Sasa & Hirabayashi, 1993 fits well with the species figured and diagnosed by Brundin (1956) as well as with specimens of this species from Norway. We present arguments for Chaetocladius volitans (Goetghebuer) comb. n. and for the use of Gymnometriocnemus kamimegavirgus for Gymnometriocnemus volitans sensu Brundin. In addition, we provide DNA barcode data that indicate the presence of at least seven Gymnometriocnemus species in Norway of which six are collected as male adults. Two of these, Gymnometriocnemus (Gymnometriocnemus) pallidus sp. n. and Gymnometriocnemus (Raphidocladius) autumnalis sp. n. are regarded as new to science and diagnosed based on adult male morphology and DNA barcodes. The species Gymnometriocnemus (Gymnometriocnemus) marionensis Sæther, 1969 is re-established and a key to all Holarctic species is provided.

Adult female of Chaetocladius insolitus Caspers, 1987 (Diptera: Chironomidae) with notes on species distribution

The adult female of Chaetocladius insolitus Caspers, 1987 (Diptera, Chironomidae) is described and discussed in the context of the generic diagnosis of adult females of the genus Chaetocladius Kieffer, 1911. In addition, distributional notes on this rare chironomid species are included.

Redescription ofChaetocladius glacialis(Lundström, 1915) comb nov.

The damaged male holotype of Hydrobaenus glacialis Lundstrom, 1915 is redescribed and transferred to the genus Chaetocladius Kieffer. The male imago is readily distinguished by the reduced antenna with 10–11 flagellomeres and by hypopygial features. The similarities with the H. lugubris group in all likelihood are due to common adaptations to ground mating.

The transfer of Orthocladius rusticus Goetghebuer to Chaetocladius with a redescription of the type (Diptera: Chironomidae)

AbstractThe holotype male of Orthocladius rusticus Goetghebuer is redescribed and the species is transferred to the genus Chaetocladius.