Niphargus boskovici S. Karaman, 1952

Švara, Vid, Delić, Teo, Rađa, Tonći & Fišer, Cene, 2015, Molecular phylogeny of Niphargus boskovici (Crustacea: Amphipoda) reveals a new species from epikarst, Zootaxa 3994 (3), pp. 354-376 : 368-370

Niphargus boskovici S. Karaman, 1952

( Figs 1 , 2 , 3 c–d, 4c–d, 5 b, d, f, h–j, 6b, c, 7c–d, 8d–f, 9d–f, 10b, d)

Niphargus (Orniphargus) boskovici S. Karaman, 1952: 45 , figs 1–10.

Niphargus boskovici boskovici S. Karaman, 1960: 81 .— G. Karaman & Ruffo 1986: 523. Niphargus boskovici S. Karaman, 1953: 145 (9), figs 5–11.— G. Karaman 2014b: 211.

Material examined. Bjelušica near Zavala, Bosnia and Hercegovina, 2 males and 2 females, date of collection 1975.

Type locality. Vjetrenica Cave, Bosnia and Hercegovina.

Distribution. Bjelušica, Zavala, Popovo polje; Duboki do, Njeguši, Kotor; Jama kod Gornje Bijenje, Gornja Bijenja, Nevesinje; Krušnica spring, Gornji Vakuf, Rama; Poganjača, Grebci, Trebinje;Reznica, Grebci, Trebinje; Vjetrenica, Zavala, Popovo polje ( Fig. 1 ).

Diagnosis. Small species with slender body, posterior margin of pleon segments with 5 or more setae, epimeral plates angulate; telson narrow, only with apical and lateral spines. Propodi of gnathopods I–II rectangular and midsized, dactyli of gnathopods with several single setae along outer margin. Pereopods V–VII progressively longer. Dactyls of pereopods III–VII with a tiny seta and tiny spine at the base of nail. Pleopods with 2 retinaculae each.

Uropod I sexually non-dimorphic (both rami subequal), uropod III sexually dimorphic, with distal article of exopodite elongated in males.

Description. Body ( Fig. 3 b, 9d). Body elongated, 7.1–10.9 mm long. Head 0.09–0.11of body length, without rostrum. Pereonite VII with 1 or 2 posteroventral setae, pleon segments I–III with 3–7 posterodorsal setae. Epimeral plates rectangular, with posterior and distal margins convex. Epimeral plates II–III with 4–7 setae posteriorly; subventrally 1 and 2 spines, respectively. Urosomites I–III with 1, 1, 0 dorsolateral spines, respectively, on each side of body. Uropod I with strong seta at base. Telson ( Fig. 10 d) length:width ratio as 1:0.9–1.05, telson cleft 0.70–0.75 of telson length. Telson with 3–5 apical spines (per lobe), 0–2 lateral spines (per lobe), neither mesial nor dorsal spines observed. Laterally 2 plumose setae on each lobe. Longest apical spines as long as 0.20– 0.33 of telson length.

Antennae I. Antenna I ( Fig. 4 c) 0.34–0.40 of the body length. Peduncle segments in ratio 1:(0.65–0.85):(0.35– 0.40), flagellum of 17–20 articles, each bearing one seta and 1 aesthetasc. Accessory flagellum biarticulated, distal article about 1/3–1/2 length of basal article.

Antenna II ( Fig. 4 d) 0.48–0.57 of antenna I length. Lengths of peduncle articles 4:5 as 1:(0.77–0.93). Flagellum II with 10–13 articles, each bearing short seta and another chemosensory seta.

Mouthparts ( Fig. 5 b, d, i, h). Left mandibular pars incisiva with 5 teeth and lacinia mobilis with 4 teeth, pars molaris triturative. Right mandibule (fig. 5b) with 4 dentate incisor blades, multidetniculated lacinia mobilis and 6 or 7 plumose setae between lacinia and triturative molar.

Mandibular palp tri-articulate, basal article without setae, middle article with 5–7 long setae along inner margin, distal article with 1 group of 3–5 A setae, 3-4 groups of B setae, 15–19 D setae and 3–5 E setae. Palp articles 2 and 3 in ratio 1:1.20–1.28.

Maxilla I ( Fig. 5 d) with 2 or 3 setae on inner lobe, outer lobe with 7 spines; inner most spine pluridentated, other spines with up to 2 denticles. Palp biarticulated, with 5–7 distal and subdistal seta. Maxilla II ( Fig. 5 f) with subequal lobes, each with a group of long apical and subapical seta. Labium ( Fig. 5 i) with inner lobes.

Maxilliped ( Fig. 5 h) inner lobe with 3 or 4 strong flattened spines and 6–8 strong plumose setae apically and subapically. Outer lobe with 8–10 strong flattened mesial spines and 4 or 5 plumose apical setae. Dactylus with setae at base of nail.

Gnathopods. Gnathopod I ( Fig. 6 b) coxa of rhomboid shape with 6–11 setae distoventrally. Article 2 length: width as 1:0.44–0.48. Article 3 with 1 row of 5–9 posteroventral setae. Length of article 5 0.76–0.81 of article 6 length. Article 5 with proximal bulb; 1 group of setae distoanteriorly; setae also on bulb and along posteromesial margin. Article 6 rectangular in shape, anterodistal corner slightly inclined. Anterior margin with 2 or 3 groups of setae (in total 10–12 setae) and anterodistal group of 9–12 setae. Posterior margin with 5 or 6 rows of setae. Palmar corner with long palmar spine, small smooth inner spine and 2 or 3 outer denticulated spines. Outer surface proximal to palmar spine with 2 long setae; inner surface with several groups of small setae. Dactylus with 5 or 6 single setae along outer margin, inner margin with small setae; nail 0.33–0.35 of the dactylus length.

Gnathopod II ( Fig. 6 c) coxa with 6–9 setae ventrodistally, width: length ratio as 1:0.97–1.05. Article 2 length: width as 1:0.31–0.36. Article 3 with one row of 4 or 5 posteroventral setae. Length of article 5 is 0.90–0.98 of article 6 length. Article 5 with proximal bulb; 1 group of setae anterodistally; setae also on bulb and along posteromesial margin. Article 6, larger than article 6 of gnathopod I (circumference of gnathopods I:II as 0.85– 0.93:1); rectangular in shape, anterodistal angle inclined and palm longer as length of article. Anterior margin with 2 or 3 groups of setae (in total 7–9 setae) and anterodistal group of 7–12 setae. Posterior margin with 5–8 rows of setae. Palmar corner with long palmar spine, small smooth inner spine and 2 outer denticulated spines. Outer surface proximal to palmar spine with 1 or 2 long setae; inner surface with several groups of small setae. Dactylus with 3–7 setae along outer margin; inner margin with small setae; nail 0.30–0.34 dactylus length.

Pereopods III–IV ( Fig. 7 b, d). Pereopods III:IV as 1:0.95–0.98; coxal plates III–IV width:length as 1:0.92– 0.96 [females], 1.05–1.07 [males]) and 1:0.92–1.11 [females], 1.15–1.16 [males], respectively; ventral margins with 5–9 setae. Dactyli with tiny spine and tiny seta at base of nail, 1 plumose seta dorsally; nail IV 0.43–0.51 of dactylus length, dactylus IV 0.36–0.40 of propodus length.

Pereopods V–VII ( Fig. 8 d–f). Coxae V–VI with anterior lobe, posterior margin with 1–3 setae, distal seta may be spine-like. Coxa VII semicircular, 1 seta posteriorly. Lengths of pereopods V:VI:VII as 1:(1.32–1.40):(1.39– 1.5); pereopod VII 0.39–0.44 of body length. Article 2 ovoid, with small posterodistal lobe, respective widths:lengths as 1:(0.71–0.79), 1:(0.63–0.73), 1:(0.58–0.71). Bases (articles 2) of pereopods V–VII with 8–15, 9– 11, 9–12 posterior setae and 4–5, 5–6, 5 anterior groups of setae and spines, respectively. Each dactylus with tiny seta and tiny spine; 1 plumose seta dorsally; nail VII 0.30–0.37 of dactylus length, dactylus VII 0.30–0.31 of propodus length.

Gills oval shaped.

Pleopods ( Fig. 10 a) inner ramus longer than outer, each ramus of 8–12 articles, 2 retinaculae on each pleopod.

Uropods I–III. Uropod I ( Fig. 9 d) basipodite with 6 or 7 lateral and 0–2 mesial spines. Endopodite with 2 groups of 6 or 7 spines and setae, and 5 apical spines. Exopodite with 2 or 3 groups of 7 spines and 5 apical spines. Endopodite:exopodite ratio as 1:1.04–1.11.

Uropod II ( Fig. 9 e) endopodite:exopodite ratio as 1:1.04–1.30.

Uropod III ( Fig. 9 f) basipodite with 1–3 lateral spines and 2–6 apical spines. Exopodite proximal article with 4–6 and 4 groups of spines, setae and plumose setae along inner and outer margin respectively. Apical article of exopodite with 4 setae laterally and 4–6 setae apically. Endopodite with 0 or 1 lateral spines and 3 or 4 spines and setae apically. Distal article of exopodite as 0.45–0.52 (males) of proximal article. Uropod III length 0.23–0. 25 of body length (males).

Remarks. The species is sexually dimorphic, males having an elongated distal article of uropod III. It seems, however, that males are rare. Most of samples in our hand contained only females and it seems that females also dominated samples of S. Karaman (1952, 1953). While this article was processed, type series was re-described; the two descriptions are similar ( G. S. Karaman 2014c).

Figures

FIGURE 1. Phylogenetic position and distribution of the studied species. Left side: Bayesian phylogenetic tree of 94 Niphargus species. Support for the nodes is labeled with color (posterior probability 1 — black, posterior probability 0.99 — grey, posterior probability> 0.95 — white). Detailed phylogenetic structure of the shaded clade containing focal species is presented on the right side. Geographic distribution of the N. zagorae, N. boskovici, N. hvarensis and N. miljeticus (blackcolored lineage in clade upper right) is presented on a bottom right map. Distribution of newly described species is presented with asterisk. Abbreviations—CRO—Croatia, BIH—Bosnia and Herzegovina, MNE—Montenegro.

FIGURE 2. Differences in proportions between N. zagorae sp. n. (circles) and N. boskovici (diamonds). Upper: The ratio propodus length: palm length of gnathopod II plotted against the body size. Lower: The ratio pereopod V length: pereopod VII length plotted against body size. We plotted body proportions against body size as some appendages may grow allometrically (Fišer et al. 2008 b). Note that values of ratio do not overlap between the two species.

FIGURE 3. Habitus and diagnostic details (arrows) on urosoma in N. zagorae sp. n. (a, b) and N. boskovici (c, d).

FIGURE 4. Antenna I and II of N. zagorae sp. n. (a, b) and N. boskovici (c, d).

FIGURE 5. Mouthparts of N. zagorae sp. n. (a, c, e, g) and N. boskovici (b, d, f, h, i, j). Mandibula (a, b), maxilla I (c, d), maxilla II (e, f), maxilliped (g, h), labrum (i), labium (j).

FIGURE 6. Gnathopods I and II of N. zagorae sp. n. (a, d) and N. boskovici (b, c).

FIGURE 7. Pereopods III and IV of N. zagorae sp. n. (a, b) and N. boskovici (c, d) with more precise drawing of dactylus of the third pereopods. Arrows indicate diagnostic difference.

FIGURE 8. Pereopods V, VI and VII of N. zagorae sp. n. (a, b, c) and N. boskovici (d, e, f).

FIGURE 9: Uropods I, II and III of N. zagorae sp. n. (a, b, c) and N. boskovici (d, e, f). Uropod III of N. boskovici is distally damaged; unfortunately it was the only adult male in analysis.

FIGURE 10. Pleopods and telson of N. zagorae sp. n. (a, c) and N. boskovici (b, d).