Paramoera (G.) myslenkovi, Sidorov, Dmitry A., 2010

Sidorov, Dmitry A., 2010, A new subgenus of eusirid amphipod (Crustacea: Amphipoda: Eusiridae) from subterranean waters and springs of the Eastern Sikhote-Alin Mountain Ridge, with comments on the morphology of sternal humps, genital papillae and pleopods, Zootaxa 2518, pp. 1-31 : 5-15

publication ID	https://doi.org/ 10.5281/zenodo.196181
DOI	https://doi.org/10.5281/zenodo.6203280
persistent identifier	https://treatment.plazi.org/id/03D0B76B-FF8A-D27C-B1FF-FC5DFE4AFCEF
treatment provided by	Plazi
scientific name	Paramoera (G.) myslenkovi
status	sp. nov.

Treatment

Paramoera (G.) myslenkovi sp. nov.

Figures 2–38 View FIGURE 2 View FIGURES 3 – 4 View FIGURES 5 – 11 View FIGURES 12 – 17 View FIGURES 18 – 22 View FIGURES 23 – 29 View FIGURES 30 – 31 View FIGURES 32 – 33 View FIGURES 34 – 39

Paramoera sp. – Sidorov & Semenchenko 2009: 133, fig. 4.

Diagnosis. Dorsal surface of body segments smooth with sparse fine setae ( Figs 2 View FIGURE 2 , 38 View FIGURES 34 – 39 ). Eyes absent ( Figs 2 View FIGURE 2 , 16 View FIGURES 12 – 17 ). Vital body color is light reddish. Head with rostral point. Inferior antennal sinus moderate, sub-rounded ( Fig. 16 View FIGURES 12 – 17 ). Antenna 1 about 40% longer than antenna 2. Epimeron 3 with 2 setae on ventral margin, but epimera 1–2 unarmed. Ventral surface of urosomite 1 bearing 2 robust and 2 slender setae. Uropod 3 has a peduncular process armed with 1 robust seta. Telson is much longer than uropod 3 peduncle. Sternal humps on the ventral surface of pereonites 2–7. Body length 4.5 – 7.0 mm (females), 5.0 – 5.2 mm (males).

Material examined. Holotype: female, 5.5 mm, 1/88500-ZINRAS, Russia, Primory Territory, Lasovsky District, ~ 3 km E of Laso, the Kievka River (43°22.160'N 133°55.485'E), 3 Aug 2009, coll. D.A. Sidorov & K.A. Semenchenko. Paratypes: 15/1sd-IBSS, 5 females, (5.6 mm, 5.5 mm, 2x 5.25 mm, 5.0 mm), 2 males (5.2 mm, 5.0 mm), with same data as holotype, the Pasechnaya River (43°22.669'N 133°54.016'E), near ford in Laso, same date and collectors as holotype.

Additional material examined (not placed in the type series): 18 females (7.0 mm, 3x 6.0 mm, 5.5 mm, 5.25 mm, 5.0 mm, 6x 4.75 mm, 5x 4.5 mm), 8 juveniles, with same data as type series, the Lasovka River (43°22.570'N 133°53.772'E), near the road bridge in Laso, same date and collectors as holotype. Deposited at the IBSS.

Description. Female (5.5 mm). Head. Antenna 1 ( Fig. 7 View FIGURES 5 – 11 ): 70% length of body, about 40% longer than antenna 2; peduncular articles 1–3 have a length ratio of 1:0.82:0.39; primary flagellum with 27 articles; next nearest flagellar articles bearing lanceolate aesthetascs accompanied by setae; calceoli absent; accessory flagellum 1-articulate, scale-like, bearing 3 setae, one of which is plumose. Antenna 2 ( Fig. 5 View FIGURES 5 – 11 ): gland cone obtuse with 2 apical setae; peduncular article 4 slightly longer than article 5, both articles setose with long setae; flagellum with 20 articles, calceoli absent, some distal flagellar articles bearing a rod-shaped structure accompanied by setae. Upper lip ( Fig. 8 View FIGURES 5 – 11 ): ovoid, with minute setae at apex. Lower lip ( Fig. 6 View FIGURES 5 – 11 ): inner lobes absent. Mandibles subequal: left mandible ( Fig. 14 View FIGURES 12 – 17 ) with incisor 6-dentate, lacinia mobilis 5-dentate, setal row with 5 serrated setae, triturative molar with long plumose seta; palp article 2 as long as article 3 with 7 setae, article 3 bearing 1 A-seta, 5 B-setae, 2 C-setae, 16 D-setae and 5 E-setae; incisor of right mandible ( Fig. 15 View FIGURES 12 – 17 ) 6- dentate, lacinia mobilis trifurcate, setal row with 6 serrated setae, one of which is comb-shaped. Maxilla 1, left ( Fig. 9 View FIGURES 5 – 11 ): inner plate with 9 plumose setae, outer plate with 10 pectinate robust setae; palp articles 1–2 have a length ratio of 0.35:1, article 2 bearing 5 robust and 3 stiff setae on apex, 1 long seta on outer face mediodistally; right palp massive ( Fig. 10 View FIGURES 5 – 11 ), articles 1–2 have a length ratio of 0.43:1, article 2 bearing 6 short strong and 1 weak setae on apex with 3 stiff setae sub-apically, 1 long seta on outer face medio-distally. Maxilla 2 ( Fig. 11 View FIGURES 5 – 11 ): inner plate with oblique row of 6 plumose setae on inner margin; outer plate broad with 16 slender setae on apex. Lateralia ( Fig. 12 View FIGURES 12 – 17 ): sub-rectangular, bearing 15 unguliform slightly pectinate setae accompanied by stiff setae. Maxilliped ( Fig. 13 View FIGURES 12 – 17 ): peduncle sub-rectangular with 2 long setae on inner face and 2 strong setae on outer face laterally; inner plate apically with 2 simple strong peg setae, 4 short setae on inner face, 12 plumose setae extending from inner margin to apex; outer plate with a row of 6 medial robust setae, 21 naked setae and 4 apical plumose setae; palp articles 1–2 have a length ratio of 0.4:1, article 2 stout with a row of simple setae on inner margin and 2 simple setae on outer margin; dactylus with 3 setae along inner margin. Pereon. Gnathopod 1 ( Fig. 3 View FIGURES 3 – 4 ): coxa deep with 7 short setae on ventral margin; basis stout with 4 long and 2 short setae on anterior margin and with 5 long and 2 short setae on posterior margin; carpus 0.8x as long as propodus; propodus of gnathopod 1 smaller than propodus of gnathopod 2; propodus sub-rectangular, palm slightly convex with cutting margin developed and armed with 4 distally notched robust setae near defining angle; posterior margin much longer than palm with 5 sets of setae; dactylus weakly dentate along inner margin with 1 seta on outer face, nail short with 2 minute setae at hinge. Gnathopod 2 ( Fig. 4 View FIGURES 3 – 4 ) larger than gnathopod 1; coxa deep with 6 short setae on ventral margin; basis sub-linear with 3 long and 6 short setae on anterior margin and with 1 set of long and 1 set of short setae on posterior margin; carpus 1.2x longer than propodus; propodus sub-rectangular, palm straight with cutting margin developed and armed with 4 distally notched robust setae near defining angle; posterior margin 2x longer than palm with 5 sets of setae; dactylus similar to that of gnathopod 1. Pereopod 3 ( Fig. 18 View FIGURES 18 – 22 ): shorter than pereopods 5–7; coxa deep with 7 short setae on ventral margin; basis sub-linear with 1 set of long setae on posterior margin; dactylus about 30% length of corresponding propodus, bearing 2 setae in base of nail. Pereopod 4 ( Fig. 19 View FIGURES 18 – 22 ): sub-similar to pereopod 3; coxa sub-quadrate with a row of 12 short setae along ventral margin. Pereopods 5–7 ( Figs 20–22 View FIGURES 18 – 22 ): sub-similar but 5 and 6 shorter than 7; coxal plates 5 and 6 bilobate, posterior lobes larger than anterior ones and armed with 1 and 2 short setae on posterior margin correspondingly; bases broad with serrated posterior margins, basis 7 with truncate disto-posterior margin, basis 5 with 1 long and 4 short setae on anterior margin, bases 6 and 7 with 1 set of shortened setae on anterior margins; dactyli 5 and 7 about 33% and 38% length of corresponding propodi, bearing 2 setae in base of nail. Coxal gills 2–7 ( Figs 4 View FIGURES 3 – 4 , 19, 21, 22 View FIGURES 18 – 22 ) stalked and saccular. Ventral surface of pereonites 2–7 ( Fig. 38 View FIGURES 34 – 39 ) bearing sternal humps (blisters). Oostegites 2–5 ( Figs 4 View FIGURES 3 – 4 , 18–20 View FIGURES 18 – 22 ) on gnathopod 2 and pereopods 3–5. Pleon. Epimera 1–3 ( Fig. 29 View FIGURES 23 – 29 ): posterior margins weakly convex but more than in plate 3, with 1 or 2 small setae; posterior corners obtuse, recessed in plate 1, acute in plate 2 and acute and recessed in plate 3, armed with 1 seta each; ventral margins of plates 1 and 2 without setae, plate 3 with 2 strong setae. Pleopods 1–3 ( Fig. 27 View FIGURES 23 – 29 ): subequal, peduncular articles with 2 retinacula each and a sparse sets of fine setae on inner, outer and medial margins; 3 bifurcate setae on outer margin of first article of inner ramus; small process enclosed with 4 plumose setae ( Fig. 28 View FIGURES 23 – 29 ) on the inner face of the first articles of outer rami; rami sub-equal in length and fringed with plumose setae. Urosome ( Fig. 17 View FIGURES 12 – 17 ): urosomites with sparse fine setae on dorsal margin; urosomite 1 saddle-shaped dorsal with 2 robust and 2 slender setae on ventral margin. Uropod 1 ( Fig. 23 View FIGURES 23 – 29 ): peduncle with 5 setae on outer margin and 4 setae on inner margin; outer ramus 0.85x as long as inner ramus, 50% length of peduncle; both rami armed with setae on outer margins; inner margin of outer ramus unarmed, but those of inner ramus with 1 seta; rami with 4 setae on apices, two of them very long. Uropod 2 ( Fig. 24 View FIGURES 23 – 29 ): peduncle with 2 setae on outer margin and 3 setae on inner margin; outer ramus 0.73x as long as inner ramus, approximately 65% length of peduncle; both rami armed with 1 or 2 setae on outer margins; inner margin of outer ramus unarmed, but those of inner ramus with 2 setae; rami with 4 setae on apices, two of them very long. Uropod 3 ( Fig. 25 View FIGURES 23 – 29 ): biramous; peduncle with a peduncular process armed with 1 robust seta, 3 setae on outer and 1 seta on inner margin; outer ramus slightly shorter than inner ramus, 1.75x as long as peduncle; rami lanceolate, armed with notched setae accompanied with plumose setae on outer and inner margins with 1 simple seta each sub-apically. Telson ( Fig. 26 View FIGURES 23 – 29 ): 1.25x as long as uropod 3 peduncle; 0.6x longer than broad, cleft about 75% of its length; tips of lobes notched with 2 setae apically, one of them long.

Male (5.0 mm, apparently immature). Similar to female but with smaller body size and differing in the following characteristics. Head. Antenna 1 and 2 without calceoli. Pereon. Gnathopod 1 ( Fig. 30 View FIGURES 30 – 31 ): propodus of gnathopod 1 smaller than those of gnathopod 2; coxa deep; carpus as long as propodus; propodus subrectangular, palm weakly convex, armed with 6 distally notched robust setae near defining angle; posterior margin longer than palm with 5 sets of setae; dactylus weakly dentate along inner margin. Gnathopod 2 ( Fig. View FIGURES 30 – 31

31) larger than gnathopod 1; coxa deep; carpus slightly longer than propodus; propodus sub-rectangular, palm straight, armed with 6 distally notched robust setae near defining angle; posterior margin much longer than palm with 5 sets of setae; dactylus similar to gnathopod 1. Coxal gills 2–7 stalked and saccular; barely visible genital papillae on ventral surface of pereonite 7; small sensory seta near base of genital papillae. Pleon. Pleopods 1–3 ( Fig. 32 View FIGURES 32 – 33 ): pleopods 1 and 3 ordinary, similar to female; pleopod 2 modified, number of articles reduced in both rami; outer ramus stout, some longer than inner ramus with 8 oblique articles, 2 last articles with a pair of strong and relatively short plumose setae, terminal article minute with a pair of plumose setae, one of them very short. Telson ( Fig. 33 View FIGURES 32 – 33 ) similar to female but with a few setae.

Taxonomic comments. The characteristics distinguishing the new species from the close P. (G.) tiunovi sp. nov. are discussed below. Among the Far Eastern Paramoera species, P. (G.) myslenkovi sp. nov. more resembles P. k o y s a m a Kuribayashi & Kyono, 1995 (see Table 1).

Type locality. Russia, Far East, southeast part of Sikhote-Alin Mountain Ridge (43°22.160'N 133°55.485'E), the Kievka River, subterranean waters (see Fig. 1 View FIGURE 1 ).

Ecology. The amphipod P. (G.) myslenkovi sp. nov. inhabits subterranean freshwaters in the Kievka River basin. The groundwater intake from a hand pump was at a depth of 1.2 m. The subterranean amphipods Pseudocrangonyx sp. and blind asellid isopods were collected from this same locality. The coxal gills of some specimens were parasitized by the suctorial infusoria Dendrocometes ( Figs 19, 21, 22 View FIGURES 18 – 22 ).

Females had different degrees of marsupial plate development, but there were no offspring or eggs in the marsupiums.

Etymology. Species named in honor of famous mammalogist Alexander Ivanovich Myslenkov (Lasovsky State Nature Reserve, Laso).