WoRMS taxon details
Ischyrocerus camptonyx Thurston, 1974
237424 (urn:lsid:marinespecies.org:taxname:237424)
accepted
Species
marine, brackish, fresh, terrestrial
recent only
Thurston, M. H. (1974). The Crustacea Amphipoda of Signy Island, South Orkney Islands. <em>British Antarctic Survey Scientific Reports.</em> 71: 1-133.
page(s): 95 [details] Available for editors
[request]
page(s): 95 [details] Available for editors
[request]
Type locality contained in South Orkney Island
type locality contained in South Orkney Island [details]
Status Ischyrocerus camptonyx Thurston, 1974b from subantarctic Signy Island is not Ischyrocerus. It is possibly an undescribed...
Status Ischyrocerus camptonyx Thurston, 1974b from subantarctic Signy Island is not Ischyrocerus. It is possibly an undescribed species of Jassa or synonymous with J. alonsoae, in which case Thurston’s name would take precedence. Jassa thurstoni Conlan, 1990 (called J. falcata form 2 by Thurston) and Pleojassa moorei n. sp. (called J. falcata form 3) are also known from Thurston’s collections there. For I. camptonyx, hallmarks of the genus Jassa, rather than Ischyrocerus are the spines at the tip of the antenna 2, the sinuous palmed gnathopod 2, the strong overlap of the merus over the carpus on pereopods 3 and 4, the typical Jassa-like uropod 3 with long peduncle lacking mid-dorsal spines (but with a corona of spines around the distal margin), a lateral setal brush and the strong hooked spines at the tip of the outer ramus, and the telson with a long seta at each corner rather than a spine. However, Thurston describes the uropod outer ramus “with three stout hooked spines dorsally near apex and a minute comb with five-six teeth laterally”, which does not correspond to his illustration and are not Jassalike. Possibly, though, his description could be interpreted differently. One of the three spines may be the apically immersed, dorsally recurved spine typical of Jassa, the other two spines are cusps, and the five–six teeth are minutedorsal cusps proximal to the two large ones. If so, then this also speaks of I. camptonyx as being a Jassa, either its own species or synonymous with J. alonsoae. It is not a Pleojassa, even though the male’s second-gnathopod resembles that of P. moorei, because this genus lacks a gill on gnathopod 2 while I. camptonyx possesses one. Thurston considered that the few males available for study were juvenile because they all lacked a thumb as in Jassa. However, some of these specimens were larger than the adult, ovigerous females. The female allotype was 4.5 mm and the male holotype was 5.5 mm. This suggests that the male holotype is actually an adult that will not produce a thumb, in which case it is not Jassa. Therefore, until the range of variation can be assessed in Thurston’s specimens, this species should remain in Ischyrocerus with a question as to its proper generic placement. [details]
Horton, T.; Lowry, J.; De Broyer, C.; Bellan-Santini, D.; Copilas-Ciocianu, D.; Corbari, L.; Costello, M.J.; Daneliya, M.; Dauvin, J.-C.; Fišer, C.; Gasca, R.; Grabowski, M.; Guerra-García, J.M.; Hendrycks, E.; Hughes, L.; Jaume, D.; Jazdzewski, K.; Kim, Y.-H.; King, R.; Krapp-Schickel, T.; LeCroy, S.; Lörz, A.-N.; Mamos, T.; Senna, A.R.; Serejo, C.; Souza-Filho, J.F.; Tandberg, A.H.; Thomas, J.D.; Thurston, M.; Vader, W.; Väinölä, R.; Valls Domedel, G.; Vonk, R.; White, K.; Zeidler, W. (2024). World Amphipoda Database. Ischyrocerus camptonyx Thurston, 1974. Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=237424 on 2024-04-27
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original description
Thurston, M. H. (1974). The Crustacea Amphipoda of Signy Island, South Orkney Islands. <em>British Antarctic Survey Scientific Reports.</em> 71: 1-133.
page(s): 95 [details] Available for editors [request]
basis of record De Broyer, C.; Lowry, J.K.; Jazdzewski, K. & Robert, H. (2007). Catalogue of the Gammaridean and Corophiidean Amphipoda (Crustacea) of the Southern Ocean, with distribution and ecological data. In: De Broyer C. (ed.). Census of Antarctic Marine Life: Synopsis of the Amphipoda of the Southern Ocean. Vol. I. <em>Bulletin de l'Institut royal des Sciences naturelles de Belgique, Biologie.</em> 77, suppl. 1: 1-325. [details]
status source Conlan, K. E. (2021). New genera for species of <em>Jassa</em> Leach (Crustacea: Amphipoda) and their relationship to a revised Ischyrocerini. <em>Zootaxa.</em> 4921(1): 1-72., available online at https://doi.org/10.11646/zootaxa.4921.1.1 [details] Available for editors [request]
page(s): 95 [details] Available for editors
[request] basis of record De Broyer, C.; Lowry, J.K.; Jazdzewski, K. & Robert, H. (2007). Catalogue of the Gammaridean and Corophiidean Amphipoda (Crustacea) of the Southern Ocean, with distribution and ecological data. In: De Broyer C. (ed.). Census of Antarctic Marine Life: Synopsis of the Amphipoda of the Southern Ocean. Vol. I. <em>Bulletin de l'Institut royal des Sciences naturelles de Belgique, Biologie.</em> 77, suppl. 1: 1-325. [details]
status source Conlan, K. E. (2021). New genera for species of <em>Jassa</em> Leach (Crustacea: Amphipoda) and their relationship to a revised Ischyrocerini. <em>Zootaxa.</em> 4921(1): 1-72., available online at https://doi.org/10.11646/zootaxa.4921.1.1 [details] Available for editors
[request] 
Present Present in aphia/obis/gbif/idigbio Inaccurate Introduced: alien Containing type locality
From editor or global species database
Status Ischyrocerus camptonyx Thurston, 1974b from subantarctic Signy Island is not Ischyrocerus. It is possibly an undescribed species of Jassa or synonymous with J. alonsoae, in which case Thurston’s name would take precedence. Jassa thurstoni Conlan, 1990 (called J. falcata form 2 by Thurston) and Pleojassa moorei n. sp. (called J. falcata form 3) are also known from Thurston’s collections there. For I. camptonyx, hallmarks of the genus Jassa, rather than Ischyrocerus are the spines at the tip of the antenna 2, the sinuous palmed gnathopod 2, the strong overlap of the merus over the carpus on pereopods 3 and 4, the typical Jassa-like uropod 3 with long peduncle lacking mid-dorsal spines (but with a corona of spines around the distal margin), a lateral setal brush and the strong hooked spines at the tip of the outer ramus, and the telson with a long seta at each corner rather than a spine. However, Thurston describes the uropod outer ramus “with three stout hooked spines dorsally near apex and a minute comb with five-six teeth laterally”, which does not correspond to his illustration and are not Jassalike. Possibly, though, his description could be interpreted differently. One of the three spines may be the apically immersed, dorsally recurved spine typical of Jassa, the other two spines are cusps, and the five–six teeth are minutedorsal cusps proximal to the two large ones. If so, then this also speaks of I. camptonyx as being a Jassa, either its own species or synonymous with J. alonsoae. It is not a Pleojassa, even though the male’s second-gnathopod resembles that of P. moorei, because this genus lacks a gill on gnathopod 2 while I. camptonyx possesses one. Thurston considered that the few males available for study were juvenile because they all lacked a thumb as in Jassa. However, some of these specimens were larger than the adult, ovigerous females. The female allotype was 4.5 mm and the male holotype was 5.5 mm. This suggests that the male holotype is actually an adult that will not produce a thumb, in which case it is not Jassa. Therefore, until the range of variation can be assessed in Thurston’s specimens, this species should remain in Ischyrocerus with a question as to its proper generic placement. [details]
