Pseudocrangonyx sympatricus Sidorov & Gontcharov
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publication ID |
https://doi.org/ 10.11646/zootaxa.3693.4.8 |
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publication LSID |
lsid:zoobank.org:pub:A6973F27-B9FA-4C3E-A2C3-BB4C1BBCE1E0 |
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DOI |
https://doi.org/10.5281/zenodo.5657803 |
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persistent identifier |
https://treatment.plazi.org/id/F21A8787-FF82-F711-E6A6-FF6AFCE04DD3 |
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treatment provided by |
Plazi |
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scientific name |
Pseudocrangonyx sympatricus Sidorov & Gontcharov |
| status |
sp. nov. |
Pseudocrangonyx sympatricus Sidorov & Gontcharov View in CoL , sp. nov.
( Figs 3 View FIGURE 3 C, 70–90)
Diagnosis. Small-sized species, sexual dimorphism unknown. Dorsal surface of body segments smooth ( Figs 3 View FIGURE 3 C, 71), teretial, bearing detached fine setae. Eyes absent. Body unpigmented. Interantennal lobe of the head rounded, slightly tapered; inferior antennal sinus moderate ( Fig. 70 View FIGURES 70 – 78 ). Antenna 1 about 30% length of body. Palp mandible article 3 with 2 B-seta, 11 D-setae and 3 E-setae. Ventral surface of pereonites 2–7 with sternal humps (blisters). Pereopod 7 largest. Urosome without “ecdysial setae”. Uropod 1 with 1 basofacial seta. Telson emarginated. Body length 5.2–6.25 mm (females).
Type locality. Russia, Far East, southeast part of the Sikhote-Alin Mountain Ridge, the Kievka River basin (43º22.160' N 133º55.485' E), subterranean waters (hyporea), 217 m above sea level.
Material examined. Holotype: female (6.25 mm, oostegites undeveloped), X38655 View Materials /Cr-1471-FEFU, Russia, Primory Territory, Lasovsky District, ~ 3 km E of Laso, Kievka River (43º22.160' N 133º55.485' E), 3 Aug 2009, coll. D.A. Sidorov & K.A. Semenchenko. Paratypes: 11/8sd-IBSS, sex unknown (4.5 mm); with same data as holotype. Closely with type locality, 15 Jun 2011, coll. D.A. Sidorov & A.L. Sidorov, 2 females (5.7 mm, 5.2 mm, oostegites undeveloped).
Etymology. The species name sympatricus (adj.) indicate to the sympatry of this species with the congeneric Pseudocrangonyx kseniae . Gender masculine.
Description. Female (6.25 mm), X38655 View Materials /Cr-1471-FEFU. Head. Antenna 1 ( Fig. 73 View FIGURES 70 – 78 ): about 30% length of body, 60% longer than antenna 2; peduncular articles 1–3 in length ratio 1:0.9:0.4; primary flagellum with 17 articles; aesthetascs present. Antenna 2 ( Fig. 74 View FIGURES 70 – 78 ), peduncular articles 4 and 5 in lengths ratio 0.9:1; flagellum with 7 articles; calceoli absent. Left mandible ( Fig. 81 View FIGURES 79 – 84 ) incisor 5-dentate; lacinia mobilis 5-dentate; setal row with 4 serrate setae. Right mandible incisor 5-dentate; lacinia mobilis trifurcate. Molar process triturative, with accessory seta. Palp mandible article 3 63% longer article 2; article 3 with 2 B-seta, 11 D-setae and 3 E-setae. Lower lip ( Fig. 83 View FIGURES 79 – 84 ), inner lobes absent; mandibular process indistinct (roundish). Maxilla 1 ( Fig. 79 View FIGURES 79 – 84 ), inner plate with 3 plumose setae; outer plate with 7 serrate setae; palp article 2 about 3.7× longer than article 1 bearing 3 stiff setae on apex. Maxilla 2 ( Fig. 80 View FIGURES 79 – 84 ), inner plate with 4 plumose setae. Maxilliped ( Fig. 84 View FIGURES 79 – 84 ) inner plate with 2 short and 1 long simple setae apical and 4 plumose setae sub-apical; outer plate with a row of 7 medial robust setae two of them serrate, 3 apical long stiff setae. Pereon. Coxal plates 1–4 ( Figs 85–87 View FIGURES 85 – 90 ) shallow, sub-rectangular. Gnathopod 1 ( Fig. 85 View FIGURES 85 – 90 ), carpus 0.5× as long as propodus, rastellate setae absent; propodus palm oblique, defining angle indistinct, palm with cutting margin crenulated, palm with 10 distally notched robust setae in two rows and 6 distally notched robust setae near defining angle; dactylus, inner margin dentate, with 2 setae along outer margin. Gnathopod 2 ( Fig. 86 View FIGURES 85 – 90 ), carpus 0.7× as long as propodus, with 3 rastellate setae; propodus palm oblique, defining angle indistinct, palm with cutting margin crenulated, palm with 6 distally notched robust setae in 2 rows and 4 distally notched robust setae near defining angle; dactylus similar to that of gnathopod 1. Pereopods 3 and 4 ( Fig. 87 View FIGURES 85 – 90 ) with a row of long and short setae on posterior margin; carpus longer than propodus. Coxal gill 7 absent. Pereopod 7 ( Figs 88, 89 View FIGURES 85 – 90 ) longer than pereopod 6. Ventral surface of pereonites 2–7 bearing sternal humps (blisters). Pleon. Epimera 1–3 ( Fig. 72 View FIGURES 70 – 78 ): posterior corners obtuse, armed with 1 stiff seta each; ventral margin of plate 1 without setae, plate 2 with 2 setae and plate 3 with 2 setae. Pleopods 1–3 ( Fig. 90 View FIGURES 85 – 90 ), peduncular articles with 2 coupling setae (retinaculae). Urosome ( Figs 3 View FIGURE 3 C, 71): urosomite 1, “ecdysial setae” absent. Uropod 1 ( Fig. 75 View FIGURES 70 – 78 ): peduncle with 6 setae on outer margin, 4 setae on inner margin two of them couple and very long, 1 basofacial seta; outer ramus 0.7× as long as inner ramus, about 60% length of peduncle; inner ramus armed with 6 setae on both margins and with 2 long setae on ventral face; outer margin of outer ramus armed; rami with 5–6 setae on apices, one or two of them very long. Uropod 2 ( Fig. 76 View FIGURES 70 – 78 ): peduncle with 3 setae on outer margin and 4 setae on inner margin two of them couple; outer ramus 0.6× as long as inner ramus; inner ramus 1.4× longer peduncle, armed with setae on both margins; outer margin of outer ramus unarmed; rami with 4 setae on apices, one of them long. Uropod 3 ( Fig. 77 View FIGURES 70 – 78 ): uniramous; peduncle with 1 set of stiff setae on distal margin; proximal article of outer ramus 2.4× as long as peduncle, bearing 6 sets of setae on inner and outer margins; terminal article 0.2× as long as proximal article, with 3 setae on apex. Telson ( Fig. 78 View FIGURES 70 – 78 ): 1.2× as long as uropod 3 peduncle; 0.2× longer than broad, emarginated; tips of lobes with 2 strong setae apically, one of them long. Oostegites 2–5 on gnathopod 2 and pereopods 3–5 unmatured (barely visible), without marginal setae.
Male. Unknown.
Variability. The species is not extremely variable. The character of variability of outer rami of uropods 1 and 2 is common with above described species.
Taxonomic comments. P. sympatricus , sp. nov. is distinguished from sympatric P. kseniae by the following characteristics (characteristics of the latter in parentheses): inteantennal lobe obtuse (truncate); antenna 1 about 30% length of body (50%); antenna 2 about 0.4x shorter than antenna 1 (0.5x); peduncular articles 4, 5 of antenna 2 in length ratio 1:0.9 (1:0.5); gland cone of antenna 2 tapered (obtuse); serrate setae on outer plate of maxilliped present (absent); maxilla 2 with 4 plumose setae in oblique row (2 setae); vestigial inner lobes of lower lip absent (present); female gnathopod 1 with 6 notched setae at defining angle (9 setae); pereopod 7 longer than pereopod 6 (shorter); distal margin of epimeron 1 armed (unarmed); uropod 3 with 6 sets of setae (with 2 sets); outer rami of uropods 1, 2 in female armed (unarmed); telson 1.2× as long as uropod 3 peduncle (1.8× – 2.0×); telson emarginated (entire).
P. sympatricus , sp. nov. resembles P. korkishkoorum by distinctly short palp article 2 of mandible. The shape and structure of uropod 3 with 6 sets of setae on the proximal article of outer ramus and short terminal article is similar in P. shikokunis and P. asiaticus sensu Ueno, 1966 . The character setation of inner and outer plates of maxilliped and longer pereopod 7 are unique features distinguishing P. sympatricus , sp. nov. from all known species of the genus.
Distribution and Ecology. Known only from type locality, where it occurs together with P. kseniae . Stygobiont crustaceans Paramoera (Ganigamoera) myslenkovi Sidorov, 2010 , Asellus sp., Mackinia sp., Acanthocyclops orientalis Borutzky, 1966 , Diacyclops sp., Diacyclops ex gr “ languidoides ” and several interstitial species of water mites were collected from this same locality.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.