On two new Niphargus species ( Fam . Niphargidae ) from Italy ( Contribution to the Knowledge of the Amphipoda 288 )

Two new taxa of the family Niphargidae (Crustacea Amphipoda) from Italy are presented. Niphargus rotundus, sp. n., described and figured from Montelupo Albeze, 450 m a.s.l (Cuneo, Piemonte), and Niphargus sestaputeanus, sp. n., described and figured from Sesta Godano, Passo del Rastrello, 1000 m a.s.l. (La Spezia). The both taxa, based on the morphological characters, are close to the Niphargus puteanus KochComplex and its taxonomial position within genus Niphargus is discussed.


Introduction
The fauna of the subterranean family Niphargidae (Amphipoda, Gammaridea) in Italy is presented by nearly 60 known taxa, collected in the subterranean waters in the caves, springs, lakes, hyporheic waters and other subterranean fresh-and brackish waters.The large variability of relief and geomorphology, different ecological conditions in various localities and quality of waters at one side, and highly diverse geological and zoogeographical history of Italy at the other side, has enabled the creation of a great diversity of species, most of them usually limited on the relatively restricted area.
The relatively limited distributional possibility of the animals in the subterranean waters conduct to development of numerous cryptic and pseudocryptic populations and species, where the recognition of real cryptic taxa become very difficult and often questionable.
On the other side, the similar ecological conditions in various localities, often very distant to each other, conduct to formation of similar morphological characters by very different species.In this light, the combination of use of morphological, genetical, ecological, physiological, anatomical and other studies can resolve the problem of recognition of single different taxa and its position within the family Niphargidae.
Our studies were limited on the morphological, ecological and zoogeographical data only, based on which we recognized and described two different taxa of the genus Niphargus from northern Italy, very close to Niphargus puteanus Koch, 1836.The further various studies and new samples of these taxa from other localities will show its exact taxonomical position.

Material and Methods
The collected material was preserved in the 70% ethanol.The specimens were dissected using a WILD M20 microscope and drawn using camera lucida attachment.All appendages were temporarily submersed in the mixture of glycerin and water for study and drawing.The body-length of examined specimens was measured from tip of head to end of telson using camera lucida.All illustrations were inked manually.After the end of the study, the dissected body-parts were submerged in Liquid of Faure on slides and covered by thin cover glass for permanent preservation.Some morphological terminology and seta formulae follows Karaman`s terminology (Karaman, G. 1969;1970;2012).
The advantage of use of Liquid of Faure is the possibility to remove the dissected body-parts from Liquid of Faure by water, and study it again in the various positions under the microscope.The results are established based on provided morphological, ecological and zoogeographical investigations and data.

Diagnosis (Partially, only males)
Antenna 1 shorter than half of body, peduncular articles progressively shorter, peduncular article 3 short; antenna 2 flagellum longer than last peduncular article.Mandible palpus with elevated number of B, D and E-setae.Maxilla 1 inner plate with 3 setae, outer plate with 7 spines (6 spines with one lateral tooth each), palpus not exceeding distal tip of outer plate spines.Maxilliped inner plate with 3 distal spines, palpus article 4 with 2 setae at inner margin near basis of the nail.Epimeral plates 1-3 with almost subrounded ventroposterior corner and convex posterior margin bearing many very short setae.Coxae 1-4 relatively short, coxa 4 without ventroposterior lobe, coxa 1 with subrounded ventroanterior corner Gnathopods 1-2 relatively small, remarkably setaceous, with trapezoid propodus having inclined palm, dactylus with several bunches of setae.Pereopods 3-7 stout, strong, with additional spines along inner margin.Pereopods 5-7 stout, with unlobed article 2 bearing numerous setae along posterior margin.Pleopods with 2 retinacula each.Uropod 1 elongated, with dorsointernal row of setae and dorsoexternal row of spines, inner ramus is twice as long as outer ramus, both with numerous setae and short spines.Uropod 3 elongated, inner ramus slender and elongated, outer ramus 2-articulated, second article exceeding half of first article.Telson with numerous short distal, lateral and facial spines.
Antenna 2 well developed but relatively short.Peduncular article 3 short, with distal ventral bunch of setae as long as or longer than width or article itself (fig.1C); article 4 slightly longer than article 5 (ratio: 55:49), with 3-4 ventral bunches of setae (the longest setae are longer than diameter of article itself), along lateral and dorsal side with single or bunches of short setae; article 5 at ventral margin with bunches of setae (the longest setae are longer than diameter of article itself), along lateral and dorsal side with single or bunches of short setae (fig.1C); flagellum slender, moderately setaceous, consisting of 10 articles bearing setae not exceeding diameter of articles themselves.Antennal gland cone short (fig.1C).
Mouthparts well developed.Labrum broader than long, convex distally.Labium broader than long, with short inner lobes, outer lobes entire, with convex distal margin.
Maxilla 2: both plates with marginal setae only.Maxilliped: inner plate short, with 3 distal spines and single setae (fig.4B), outer plate reaching half of palpus article 2 and bearing a row of 12 distolateral spines and distal setae; palpus article 3 at outer margin with one median and one distal bunch of setae.Palpus article 4 at outer margin with one median seta, at inner margin with 2 setae near basis of the nail (fig.4C).
Gnathopod 2: article 2 along anterior margin with row of single long setae, along posterior margin with bunches of long setae (fig.2D); article 3 at posterior margin with one bunch of setae.Article 5 nearly as long as propodus, at anterior margin with 3 bunches of setae.Propodus trapezoid, only slightly larger than that of gnathopod 1, trapezoid nearly as long as broad, along posterior margin with 9 transverse groups of setae (fig.2E); palm slightly convex, inclined nearly half of propodus-length, defined on outer face by one corner S-spine accompanied laterally by 3 serrate L-spines and 10 facial M-setae (fig.2F), on inner face by one subcorner R-spine; dactylus reaching posterior margin of propodus, along outer margin with several bunches of median setae (14 setae), at inner margin with row of numerous short setae (fig.2E).
Pereopods 3 and 4 similar to each other, moderately stout.Pereopod 3: article 2 along anterior margin with row of short setae, along posterior margin with several bunches of long setae (fig.1E); articles 4-6 of unequal length (ratio: 52:36:38), article 2 at posterior margin with 4 bunches of setae (the longest setae reaching the diameter of article itself), at anterior margin with single short spines and setae (fig.1E); article 5 at posterior margin with 3 bunches of setae (the longest setae exceeding the diameter of article itself) and single spine; article 6 along posterior margin with 6 bunches of short spines and single setae, along anterior margin 3 bunches of short setae; dactylus short and stout, much shorter than article 6 (ratio: 17:38), along inner margin with 3 single spines, at outer margin with one median seta (fig.1F); nail shorter than pedestal (ratio: 26:32).
Uropod 1 slender, peduncle without distal tubercle, but with dorsoexternal row of short spines and dorsointernal row of setae (except distal spine) (fig.4E); inner ramus only slightly longer than peduncle, with several short lateral and distal spines as well as with 6 bunches of lateral simple setae longer than spines; outer ramus reaching only half of inner ramus-length, with 3-4 distal sport spines and 4 lateral bunches of simple setae (fig.4E).
Uropod 3 slender and long: peduncle nearly twice longer than broad, with several short lateral setae and single distal short spines and setae (fig.4F); inner ramus elongated, much longer than broad (ratio: 45:10), with several very short lateral and distal setae.Outer ramus 2-articulated, long, first article slender, along outer ramus with 6 bunches of very short spines (fig.4F), along inner margin with 5 bunches of very short spines accompanied by single plumose setae not exceeding the diameter of the article itself; second article shorter than first one (ratio: 75:118), along both margins with several very short simple setae and with distal bunch of 4-5 simple setae.
Telson slightly gapping, nearly as long as broad, incised nearly 2/3 of telson-length (fig.4D); each lobe with 3-4 distal short spines as well as with 2 outer marginal short spines and single setae; two pairs of short facial spines accompanied by 0-1 short seta are attached on each lobe; a pair of short plumose setae is attached near the middle of lobes outer margin (fig.4D).

Variability
The male of 24.0 mm is very similar to the holotype, with scarce number of dorsoposterior setae on metasomal segments 1-3 and with subrounded epimeral plates 1-2 bearing a row of short setae along posterior margin and with short ventroposterior corner seta (fig.4E).Epimeral plate 3 is more quadrate, with marked ventroposterior corner defined by stronger corner seta and provided with several short setae along posterior poorly convex margin.Epimeral plate 2 is provided with 2 subventral spines, epimeral plate 3 is provided with 3 subventral spines (fig.4E).
Holotype: Male 21.0 mm.Holotype and paratype are preserved in the Karaman`s Collection in Podgorica, Montenegro.

Derivatio nominis:
The name "rotundus" is in association with the subrounded epimeral plates.

Remarks and affinities
The specimens from Montelupo Albeze are rather similar to Niphargus puteanus (Koch, in Panzer, 1836) [loc.typ.: Regensburg, Germany] based on various characters (shape of gnathopods, shape of uropods 1-3, etc.).As the original description of this species was very poor, various taxa in different localities over Europe have been designated to this species, often erroneously.
Stock redescribed this species again from Regensburg (Stock, 1974).The comparison of the specimens from this type-locality with our specimens from Montelupo, show that N. puteanus from typelocality (Regensburg) differs from specimens from Montelupo (N.rotondus) by more angular or slightly pointed epimeral plates 1-3, by longer pereopods, more narrowed coxae, by less spiniferous dactylus of pereopods 3-7, by less setaceous gnathopods 1-2, less inclined palm of propodus in gnathopods 1 and 2, more setaceous inner plate of maxilla 1, more spiniferous inner plate of maxilliped, by presence of dorsointernal row of spines on uropod 1 peduncle, etc.
From Italy is known also species with additional spines on dactylus of pereopods, Niphargus elegans Garbini, 1894 [loc.typ.: S. Pancrazio near Verona, Italy), but it differs distinctly from N. rotundus by high number of additional spines on dactylus of pereopods 3-7, by presence of tubercle on peduncle of uropod 1 in males, by different shape of gnathopods 1-2, by very acute epimeral plates 1-3, etc.
Several species of genus Niphargus with elevated number of spines on dactylus are known from France also.Most of these taxa are poorly described with unknown numerous characters, what made very difficult recognition of differences between various species.
Niphargus ladmiraulti Chevreux, 1901 [loc.typ.: Nantes, France] is with additional number of spines on dactylus of pereopods, but differs from N. rotundus by distinctly angular epimeral plates, less incised telson bearing less number of spines and setae, by slightly unequal rami of uropod 1 in males, etc.

Diagnosis
Body slender, in male's urosomal segment 1 with 1 seta on each side, urosomal segment 2 with 2 spines.Epimeral plate 3 distinctly acute, with concave posterior margin.Coxae 1-4 shallow in males; Maxilla 1 inner plate with 3-4 setae, 6 spines of outer plate with 1 lateral tooth, one spine with 2-3 teeth.Maxilliped inner plate with 4 spines.Propodus of gnathopods 1-2 longer than broad with dactylus bearing row of single and bunches of setae; L-spines are sitting laterally of S-spine.Dactylus of pereopods 3-7 with 2-3 spines at inner margin.Article 2 of pereopods 5-7 without ventroposterior lobe.Pleopods with 2 retinacula.Uropod 1 peduncle with dorsoexternal row of short spines and dorsointernal row of setae (except distal spine), inner ramus twice as long as outer one, with lateral and distal spines and simple setae.Uropod 1 peduncle with dorsointernal row of setae (except distal spine).Uropod 2 inner ramus longer than outer one, with longer distal spines.Uropod 3 in males long, outer ramus 2-articulated, second article slightly shorter than first article; in females much shorter than first article.Telson with long distal, lateral and facial spines.
Head with short rostrum and short subrounded lateral cephalic lobes and ventroanterior excavation, eyes absent.
Antenna 2 moderately slender; peduncular article 3 short, with distoventral bunch of setae (the longest setae reaching the diameter of article itself).Peduncular article 4 slightly longer than article 5 (ratio: 63:57), along ventral margin with bunches of short and long straight setae (the longest setae exceeding the diameter of article itself (fig.5B), along dorsal margin with several groups of short setae; article 5 along ventral margin with 4 bunches of long setae (the longest setae remarkably exceeding the diameter of article itself), along dorsal margin with 4-5 groups of shorter setae (fig.5B).Flagellum remarkably longer than last peduncular article (ratio: 93:57), consisting of 11 articles bearing longer setae along ventral margin and short setae along dorsal margin; antennal gland cone short (fig.5B).Mouthparts well developed.Labrum broader than long, with convex distal margin.Labium broader than long, inner lobes well developed, outer lobes subrounded distally (fig.7A).
Maxilla 2: inner plate is rather smaller than outer one, both plates with distomarginal setae (fig.6F).Maxilliped: inner plate short, with 4 distal smooth spines (fig.9A), outer plate nearly reaching half of palpus article 2, bearing distolateral row of smooth spines; palpus article 3 at outer margin with one median and one distal bunch of setae; palpus article 4 at outer margin with one median seta, at inner margin with 2 setae near basis of the nail (fig.9A).
Gnathopods 1 and 2 relatively small, with propodus nearly as large as corresponding coxa (fig.6A,  C).Gnathopod 1: article 2 stout, along anterior margin with row of numerous long single setae, along posterior margin with several bunches of long setae; article 3 at posterior margin with one bunch of setae; article 5 slightly shorter than propodus (ratio: 35:45), at anterior margin with one distal bunch of setae (fig.6A).Propodus trapezoid, slightly longer than broad (ratio: 89:75), along posterior margin with 8 transverse rows of setae (fig.6B); palm inclined almost half of propodus-length, poorly convex, defined on outer face by one corner S-spine accompanied laterally by 2-3 slender L-serrate spines and 6 long facial M-setae (fig.6B), on inner face by one short subcorner R-spine.Dactylus reaching posterior margin of propodus, along outer margin with row of single and bunches of median setae (1-2-2-2-1-2), along inner margin with row of several short setae (fig.6B).
Pereopod 4: article a at anterior margin with row of shorter setae, along posterior margin with bunches of long and short simple setae (fig.7D); articles 4-6 of unequal length (ratio: 44:35:40), article 4 at posterior margin with 4 bunches of long setae; article 5 at posterior margin with 3 groups of short spines and single setae; article 6 at posterior margin with 5 groups of short spines and single setae (fig.7D).Dactylus short and strong, much shorter than article 6 (ratio: 14:40), at inner margin with 2 strong spines, at outer margin with one median seta; nail shorter than pedestal (ratio: 22:31) (fig.7E).
Uropod 1 elongated; peduncle as long as inner ramus and provided with dorsoexternal row of short spines and dorsointernal row of 3 setae and one distal spine (fig.7F); inner ramus long and slightly bent, bearing several lateral and distal spines and 6 bunches of simple setae longer than spines; spines are longer towards distal tip of the ramus (fig.7F).Outer ramus is shorter than half of inner ramus, bearing 2 laterals and one distal group of spines, as well as one group of lateral simple setae longer than spines (fig.7F).
Uropod 3 long and slender (fig.5H); peduncle nearly twice as long as broad, bearing single lateral and distal short spines; inner ramus uniarticulated, almost as long as peduncle, with single lateral very short setae and distal bunch of spine and short setae.Outer ramus 2-articulated, linear: first article along both margins with 4-5 bunches of very short spines and single short setae.Second article slightly shorter than first one (ratio: 128:140}, along both margins with several bunches of simple setae, as well as with distal bunch of simple setae (fig.5H).
Telson nearly as long as broad (fig.7G), each lobe with 4 distal and several lateral and facial spines.
Uropod 1: peduncle with dorsoexternal row of strong spines, and with dorsointernal row of setae (except distal spine) (fig.9C); Inner ramus is remarkably shorter than peduncle (ratio: 52:87), bearing 2 lateral spines and 2 pairs of simple setae, as well as 3-4 long and short distal spines (the longest spine reaching half of ramus length (fig.9C); outer ramus distinctly shorter than inner one, bearing 2 lateral and 4 distal spines (the longest spine reaching half of ramus-length), as well as 2 simple lateral setae (fig.9C).
Uropod 3 short (fig.9F); peduncle slightly longer than broad, bearing one lateral and 2 bunches of distal spines; inner ramus is short, scale-like, shorter than peduncle, bearing one distal spine (fig.9F).Outer ramus 2-articulated: first article at outer margin with 3 bunches of long spines and one median bunch of simple setae (fig.9F); along inner margin appear 4 bunches of long spines; accompanied by one plumose seta; second article much shorter than first one (ratio: 40:122), bearing at margin and tip short simple setae.
Telson nearly as long as broad, incised slightly over half of telson-length (fig.9E); each lobe obtuse distally, bearing 4 long distal spines exceeding half of telson length (ratio: 45:65); along outer margin of each lobe are attached 2 single spines, along inner margin appears 0-1 slender small spine; on the face of the lobes appear 1-2 facial spines (fig.9E).

Variability
The length and number of spines on telson in males and females are rather variable: along outer margin of each lobe can be 2-4 spines.Inner plate of maxilla 1 is with 3-4 setae.
The number of spines on dactylus in pereopods 3-7 is 2-3; rarely single dactylus can have only one spine; dactyls can be more or less slender.Epimeral plate 3 is always with concave posterior margin.
The female of 8 mm from spring in Monte Gottero: Epimeral plate 2 poorly pointed and bearing 3 subventral setae (fig.10F); epimeral plate 3 strongly pointed, with concave posterior margin bearing several marginal setae and with 2 subventral spines (fig.10F) Telson as long as broad, incised slightly over half of telson length; lobes slightly tapering distally and bearing 4 long distal spines (the longest spine hardly exceeding half of telson-length (ratio: 37:67), along outer margin appear 1-2 long spines; facial spines and spines at inner margin of the lobes are absent (fig.10E).