Holotype : ♀ (lost), type locality unknown.

Neotype : ♀ (VVZC Eut516), Italy, Tuscany, Castelnuovo Berardenga (SI), Ponte a Bozzone, 43.3503333°N, 11.38613889°E, under tree bark, pine wood, 13 October 2003 (V. Vignoli and F. Cicconardi coll.), by designation of Vignoli et al. (2005).

Italy: Tuscany: near SP408, W of San Giovanni A Cerreto, (SI), 43.350367°N, 11.385845°E, 293, under tree bark, pine wood, 12 August 2013, leg. G. Tropea, S. Tropea, 2 ♂♂, 4 ♀♀ topotypes (GTC 352–358); Apuan Alps, 44.05079°N, 10.26472°E, 810 m, 19 July 2015, leg. G. Tropea, S. Tropea, 2 ♀♀ (GTC 648, 649); Elba Island, lrgs. A. Valle, Bianchi, 4 January 1963, 1 ♂ (MSNB 1593); Elba Island, A. Valle, Bianchi, 8 January 1963, 1 ♂♂ (MSNB 1604); Elba Island, Mt. Perone, pinewood, legs. E. Dominici, 1 ♂ (GTC 462); Valle Benedetta, hills of Livorno, Livorno, 13 May 2012, leg. G. Tropea, 1 ♀ (GTC161–168); Massa, 17 October 2011, leg. A. Rossi, 1 ♂, 1 ♀ (GTC 109, 110); Mt. Albano, Firenze, 1969, leg. Giuliani, 1 ♀♀ (MZUF 9552); Mt. Albano, Firenze, 20 September 1975, leg. Valle, Moretti, 1 ♀ (MSNB 10158); Mt. Corchia, 44.02416°N, 10.27786°E, 708 m, 19 July 2015, leg. G. Tropea, S. Tropea, 2 ♂♂, 3 ♀♀ (GTC 643–647); same data but 44.03448°N, 10.27165°E, 1126 m, 1 ♂, 1 ♀ (GTC 641, 642); Piazza al Serchio (LU), 20 September 1975, leg. A. Valle, G.L. Moretti, 4 ♂♂, 5 ♀♀ (MSNB 10137–10140, 10143, 10147, 10153, 10156, 10157); Resceto (MS), 551–614 m, 11 August 2013, leg. G. Tropea, S. Tropea, 9 ♂♂, 6 ♀♀ (GTC 328–338); near Barberino di Mugello, 44.02430°N, 11.16499°E – 44.02357°N, 11.16451°E, 450–484 m, 12 August 2013, leg. G. Tropea, S. Tropea, 4 ♂♂, 3 ♀♀ (GTC 345–351); near Livorno, 43.570116 N, 10.369947 E, July 2021, leg. Giuliano Tropea, 1 ♀ (GTC). Emilia Romagna: Pievepelago (MO), Lago Santo, 22 July 1978, leg. Daccordi, 1 ♀ (MSNV 154/11774); Ponte Modino, Pievepelago, (MO), 44.18564°N, 10.61523°E, 938 m, 20 July 2015, leg. G. Tropea, S. Tropea, 2 ♂♂, 2 ♀♀ (GTC 650–653).

Italy: Tuscany, Emilia Romagna, Marche?, Umbria?, Piemonte?, Liguria (Fig. 32).

Medium Euscorpius species, total length 26–35 mm. Variable colour in adults, from dark brown to blackish, with darker marbling on most of the body, including chelicerae. The number of trichobothria on the pedipalp manus ventral surface is four (V_1–3 + Et₁). Trichobothria est and dsb on fixed finger are respectively located distally and proximally to the notch of the fixed finger. The number of trichobothria on the pedipalp patella ventral surface is usually eight or nine (~ 65% and 27%, respectively). The number of trichobothria on pedipalp patella external surface usually is: eb = 4, eb_a = 4, esb = 2, em = 4, est = 4, et = 6. Trichobothrium i of the femur is slightly proximal to or at the same level of d. The pectinal teeth number in males is usually eight and in females mostly seven. Dorsal patellar spur well developed. Femur approximately as long as patella but it tends to be slightly shorter than patella. Carapace approximately as long as wide, but it tends to be slightly wider than long. Carinae V₁ follows an external direction to the trichobothria Et₁, without forming a Y-shape. Spinules on legs ending with a Y-shape. Ventrolateral and ventromedian carina on metasomal segment V well formed by small spaced serrulated granules.

The variation observed in 59 examined specimens (28 ♂♂, 31 ♀♀) is given below.

Pectinal teeth in males (n = 56): 7/7 (1), 8/7 (1), 8/8 (16), 8/9 (6), 9/9 (2), 9/10 (1), 10/10 (1); in total, 7 in 5.36% (3), 8 in 69.64% (39), 9 in 19.64% (11), and 10 in 5.36% (3); mean = 8.25, SD = 0.64.

Pectinal teeth in females (n = 62): ?/? (1), 6/6 (1), 6/7 (4), 7/7 (17), 7/8 (3), 8/? (1), 8/8 (4); in total, 6 in 10.17% (6), 7 in 69.49% (41) and 8 in 20.34% (12); mean = 7.10, SD = 0.55.

Pedipalp patella trichobothria Pv (n = 118): 7/7 (1), 8/7 (6), 7/9 (1), 8/8 (32), 8/9 (7), 9/9 (12); in total, 7 in 7.63% (9), 8 in 65.25% (77) and 9 in 27.12% (32); mean = 8.19, SD = 0.56.

Pedipalp patella trichobothria Pe (n = 118): et = 4/6 (1), 5/6 (7), 6/6 (43), 6/7 (5), 7/7 (3); in total, 5 in 5.93% (7), 6 in 83.90% (99), and 7 in 9.32% (11); mean = 6.03, SD = 0.39;

est = 4/3 (1), 4/4 (56), 4/5 (1), 5/5 (1); em = 4/3 (3), 4/4 (56); esb = 1/2 (1), 2/2 (58); eb_a = 3/4 (2), 4/4 (57); eb = ¾ (3), 4/4 (56).

Type A. It has a well-developed lamina tapered distally; well-developed basal constriction present; truncal flexure present; median projection with lde, ldi, and lb; internal projection distally with 8–10 tines in its crown. The number and the shape of tines of the crown varied between specimens and between the right and the left hemispermatophores.

Euscorpius concinnus was originally described using very limited characters, not very useful in identifying the species. The main characters given by Koch (1837) were Pv = 8 and dark red-brown colouring, both can be shared by different species of Euscorpiinae. The location where the specimen was collected is unknown, therefore relying on this data is not possible too. It would probably have been more appropriate to consider this species a nomen dubium, but Vignoli et al. (2005), perhaps influenced by Di Caporiacco (1950), established a neotype for it from Siena (Tuscany, Italy). This species, like the others treated here, can be considered a cryptic species, difficult to identify without data regarding the exact geographical area of collection or DNA analysis. According to our data, this species is basal to the other species treated in the phylogeny based on concatenated 16S rDNA and COI markers (Fig. 31). Probably the present populations are the result of expansions, extinctions, bottleneck, and recolonisations, taking place several times due to climatic changes during the Pleistocene. The sequence divergence in 16S marker between E. concinnus and the remaining species of the E. concinnus group ranges from 2.7% to 3.4%, the latter value being higher than that between E. concinnus and E. tergestinus, which is 3.1%. As for the trichobothrial Pv number, E. concinnus shows an average of 8.19, clearly lower than that of E. niciensis stat. nov., but higher than of the other three species treated herein. The highest percentage was of Pv = 8 in 65.25%, i.e., similar to that of E. latinus sp. nov. and E. trejaensis sp. nov., but significantly lower than E. stefaniae sp. nov. with 81.67%, and clearly higher than E. niciensis stat. nov. with 25%; and a percentage of Pv = 9 in the 27.12%, which is clearly higher than that of all species except E. niciensis stat. nov. which has a percentage of Pv = 9 of 68.89%. It must be stated that this higher value in E. concinnus could be brought about by its heterogeneity in its distributional area. In fact, in some areas this species may have a tendency to higher or lower values, and also to morphological differences, which could suggest further taxonomic divisions in it, as well as for E. niciensis stat. nov. (GT, in progress).

Ythier (2011) assigned some specimens from France to E. concinnus and E. tergestinus and reports a Pv range of seven and eight for E. concinnus and from seven to eleven (nine) for E. tergestinus. However, no additional data are provided for these claims. Euscorpius tergestinus is limited to the Balkans and to the Italian areas near the border with Slovenia (Tropea, 2013). Considering Ythier’s data, his E. tergestinus and E. concinnus populations probably were E. niciensis stat. nov. We found no populations with such low fixed trichobothrial data neither in the specimens examined from France nor in those from western Liguria in Italy. Therefore, in the absence of further data, we consider that the range of this species is limited within Italy.

The current distributional range of E. concinnus is not easily delineable yet. We consider it an endemic species of Italy, found in Tuscany, Liguria, and Emilia Romagna, and with doubtful presence in the regions of Piedmont, Lombardy, Umbria and Marche. Euscorpius concinnus was found up to an altitude of 1126 m a.s.l., in the Apuan Alps. It is found mostly in woods, both under stones and bark, but also in humid microhabitats in pine forests, and more rarely in human-made constructions, in wall cracks, and in the areas around the walls.

Holotype : ♂, Italy, Latium, Lepini Mts, near Montelanico (RM), 470 m a.s.l., 41.631314°N, 13.026798°E, 20 June 2013, leg. G. Tropea (GTC).

Paratypes: Italy: Latium: Lepini Mts, near Montelanico (RM), 470 m a.s.l., 41.631314°N, 13.026798°E, 20 June 2013, leg. G. Tropea, 2 ♂♂, 4 ♀♀ (GTC paratypes); same data but 444 m a.s.l., 41.63219°N, 13.02634°E, 1 ♂, 5 ♀♀ (GTC paratypes); same data but 456–467 m, 41.63118°N, 13.02580°E, 41.63092°N, 13.02530°E, 41.63156°N, 13.02547°E, 12 August 2020, leg G. Tropea, 4 ♂♂, 3 ♀♀ (GTC paratypes); Castel Fusano, Rome, 8 April 2012, leg. G. Tropea, 6 ♂♂, 7 ♀♀ (GTC paratypes); Castel Fusano, Rome, ~ 9 m a.s.l., around to 41,73064°N, 12,31516°E, 22 June 2014, leg. G. Tropea, 3 ♂♂, 4 ♀♀ (GTC paratypes); Near Sabaudia (LT), 18 August 2009, leg. G. Tropea, 3 ♂♂ (GTC paratypes); same data but 5 May 2012, leg. G. Tropea, 3 ♀♀ (GTC paratypes); surroundings of Anticoli Corrado (RM), under stones, 42.012665°N, 12.970851°E, May 2014, leg. A. Massimiani, 2 ♀♀ (GTC paratypes); Near Monterotondo (RM), 109 m a.s.l., 42.06871°N, 12.64305°E, 18 April 2014, leg. G. Tropea, 2 ♂♂, 1 ♀ (GTC paratypes); Simbruini Mts., near Trevi nel Lazio (FR), 1 August 1976, leg. R. Argano, 1 ♂, 1 ♀ (GTC paratypes). Molise: Near SP Carovillense, Villa San Michele (IS), 41.74463°N, 14.23146°E, 14 July 2012, leg. G. Tropea, S. Tropea, 5 ♂♂, 1 ♀ (GTC paratypes).

(not included in type series). Italy: Latium: Mt. Gennaro, Lucretili Mts., (RM), ~ 1000 m a.s.l., 24 August 2009, G. Tropea, 2 ♂♂, 2 ♀♀ (GTC).

The specific epithet means Latin, due to its range which includes the first area in which the Latins and the Latin language spread, namely the Latium vetus.

Italy: Latium (left of the Tiber River; Fig. 32).

A medium-small, Euscorpius species, total length 25–34 mm. Colour of adults mostly dark brown with darker marbling on most of the body, including chelicerae, but with rare blackish or medium brown specimens. The number of trichobothria on the pedipalp manus ventral surface is four (V_1–3 + Et₁). Trichobothria est and dsb on fixed finger are respectively located distally and proximally to the notch of the fixed finger. The number of trichobothria on the pedipalp patella ventral surface is usually eight and seven (seven in 39.68% of the pedipalps examined). The number of trichobothria on pedipalp patella external surface is usually: eb = 4, eb_a = 4, esb = 2, em = 4, est = 4, et = 6 (5–7). Trichobothrium i of the femur is slightly proximal to or at the same level of d. The pectinal teeth number in males usually is eight (7–9) and in females usually is seven (6–8). Dorsal spur well developed. Femur is slightly shorter than the patella. Carapace tends to be shorter than long. Carinae V₁ follows an external direction to the trichobothria Et₁, without forming a Y-shape. Spinules on legs ending with a Y-shape. Ventrolateral and ventromedian carina on metasomal segment V well formed by small, spaced and slightly serrulated granules.

The variation observed in 63 examined specimens (29 ♂♂ and 34 ♀♀) is given below (left/right asymmetry not specified).

Pectinal teeth in males (n = 58): 7/7 (1), 7/8 (2); 8/8 (20), 8/9 (2), 9/9 (4); in total, 7 in 6.90% (4), 8 in 77.59% (45), and 9 in 17.24% (10); mean = 8.10, SD = 0.48.

Pectinal teeth in females (n = 67): 5/6 (1), 6/6 (2), 6/7 (7), ?/7 (1), 7/7 (15), 7/8 (6), 8/8 (2); in total, 6 in 17.91% (12), 7 in 65.67% (44), and 8 in 14.92% (10); mean = 6.94, SD = 0.62.

Pedipalp patella trichobothria Pv (n = 126): 7/7 (15), 7/8 (20), 8/8 (28); in total, 7 in 39.68% (50), and 8 in 60.32% (76); mean = 7.60, SD = 0.49.

Pedipalp patella trichobothria Pe (n = 81): et = 5/4 (1), 5/5 (3), 5/6 (5), 6/1 (1), 6/6 (29), 4/7 (1); in total, 4 in 2.46% (2), 5 in 17.28% (14), 6 in 79.01% (64), and 7 in 1.23% (1); mean = 5.79, SD = 0.49;

est = 4/3 (1), 4/4 (38), 4/5 (2); em = 3/4 (7), 4/4 (33), 4/5 (1); esb = 2/2 (41); eb_a = 4/4 (41); eb = 4/4 (39), 4/5 (2).

Colouration. A general dark brown base colour with more or less marked lighter marbling or reticulation, reddish brown, in the less granulated areas, especially of the metasoma, legs, pedipalps and chelicerae; telson mostly dark brown with two ventrally longitudinal pale brown stripes and one for each side, with reddish brown distal part of the sting; pale brown chelicerae with dark brown reticulation; chelae with fingers ranging from pale yellowish brown to dark reddish brown with dark blackish brown reticulation; legs with most ivory tarsus, the basitarsus and tibia are mostly pale brown, but with dark blackish brown marbling externally, almost pale brown internally, the patella and femur are mostly dark with paler spot externally, and mostly pale brown with dark reticulation internally; pectines and genital operculum whitish ivory; sternites are mostly very pale brownish but the most distal is laterally dark blackish brown with the central part pale brown.

Carapace. Almost completely covered by dense fine granules, especially on the dark marbling. The granules in the lateral anterior part are larger; anterior edge is straight with some granules; deep posterior lateral furrows; two pairs of lateral eyes, and a pair of median eyes; length from centre of median eyes to anterior margin is 40.48% of carapace length.

Mesosoma. The tergites are densely covered with a fine granulation; sternites glossy and finely punctuated; small spiracles inclined to ~ 40° downward towards outside.

Metasoma. Dorsal carinae on segments I–IV with spaced granules; ventrolateral carinae on segment I absent, on segment II and III smooth or obsolete, on segments IV, little marked with some small and spaced granule, with small slightly serrulated granules on segment V; ventromedian carinae absent on segment I–III, little marked smooth or obsolete on segment IV, on segment V it consists of small, slightly serrulated granules, which expands like a fan in the most distal part; dorsal and lateral intercarinal surfaces on segments I–IV are mostly finely granulated, especially on dark marbling, while the ventral surfaces are mostly smooth, the V segment is mostly finely granulated.

Telson. Vesicle with a few small granules, with ventral setae of different size, especially near the vesicle/aculeus juncture.

Pectines. Teeth number 8/8; middle lamellae number 5–5; several microsetae on proximal area of teeth, marginal lamellae, and middle lamellae.

Genital operculum. The genital operculum is formed by two longitudinally devised subtriangular sclerites with genital papillae protruding.

Sternum. Pentagonal shape, type 2; slightly wider than long, with a deep posterior emargination.

Pedipalps. Coxa and trochanter with tuberculated carinae. Femur: dorsal internal and external and ventral internal carinae tuberculated; irregular ventral external carinae formed by tubercles just on 1/3 or 1/4 of femur length; external median carinae formed by lightly serrulated tubercles; anterior median carinae formed by some spaced conical tubercles; intercarinal spaces granulated. Patella: dorsal and ventral internal carinae tuberculated; ventral external carinae crenulated; dorsal external carinae slightly crenulated to rough; intercarinal surfaces finely granulated, especially on the dark reticulations near the internal carinae. Dorsal patellar spur well developed. Chela: chelal carina D₁ is distinct, strong, dark and smooth with a few tubercles; D₄ is rounded with a few spaced granules; V₁ is distinct, strong, dark, from rough to smooth, following an external direction to the trichobothria Et₁; V₃ is rounded with scattered granules; external carina granulated; intercarinal tegument granulated; the fixed and movable fingers with medium notch and lobe, respectively.

Finger dentition. In the most distal part is present a DD on the tip; MD is formed by very small denticles closely spaced forming an approximately straight line, discontinued at level of the OD; fixed finger has 5/5 OD and 11/10 ID; movable finger has 7/7 OD and 13/15 ID.

Trichobothria. Chela: trichobothria on the pedipalp manus ventral surface V = 2*/3 (V_1–3) (*the trichobothrium V3 of the left chela is vestigial) + Et₁ = 1/1; trichobothrium V₄ situated on the external surface of the chela, near the carina V₁; trichobothrium ratio of et-est/est-dsb is ~ 0.95 and 0.87. Trichobothrium est is distal to the centre of the notch of the fixed finger and dsb is proximal. Patella: Pv = 8/7; et = 6/6, est = 4/4, em = 4/4, esb = 2/2, eb_a = 4/4, eb = 4/4. Femur: trichobothrium d is slightly proximal to i, while trichobothrium e is well distal to both d and i, and situated on dorsal surface on dorsal external carina.

Legs. Two pedal spurs present; no tarsal spur; ventral row of tarsus with a total of 12/10 spinules on leg III, of increasing size from proximal to distal, ending with two spinules to form a Y-shape; three main flanking tarsal setae present. Tubercles present on ventral and dorsal surface of all leg femora.

Chelicerae. Typical of the genus Euscorpius.

Type A. It has a well-developed lamina tapered distally; well-developed basal constriction present; truncal flexure present; median projection with lde, ldi, and lb; internal projection distally with 9–11 tines in its crown. The number and the shape of tines of the crown varied between specimens and between the right and the left hemispermatophores.

Euscorpius latinus sp. nov. is the southernmost species of the E. concinnus group. The geographically closest species of the E. concinnus group is E. trejaensis sp. nov., which seems to be divided from Euscorpius latinus sp. nov. by the Tiber River. However, in terms of both phylogeny and of DNA sequence divergences, these two species do not seem to be more closely related compared to the others. In fact, according to the concatenated phylogenetic tree 16S rDNA + COI presented herein (Fig. 31), E. latinus sp. nov. is placed between E. concinnus, which is more basal to it, and the other species, which are apical to it. Regarding the sequence divergence in 16S marker, between E. latinus sp. nov. and E. trejaensis sp. nov., it ranges from 2.7% to 3.1%, as with E. niciensis stat. nov., from 3% to 2.7% with E. concinnus and from 3.8% to 4.2% with E. stefaniae sp. nov. Morphologically, like the other species of the E. concinnus group and the many cryptic species complex that have been described in recent years, E. latinus sp. nov. is difficult to identify without reference to the locality of origin or with a limited number of specimens. As for the trichobothrial and pectines teeth values, E. latinus sp. nov., together with E. trejaensis sp. nov., has the lowest average of Pv, which is 7.60 and 7.62, respectively, having the highest percentage of Pv = 7, i.e., 39.68%, vs. percentages ranging from 2.78% to 13.33% in E. concinnus, E. niciensis stat. nov. and E. stefaniae sp. nov. and a very similar percentage in E. trejaensis sp. nov., 34.07. While the percentage of Pv = 8 is very similar to both E. concinnus and E. trejaensis sp. nov. (from 60.32%–65.25%), it is very different from that of E. niciensis stat. nov. and E. stefaniae sp. nov. (25% and 81.67, respectively). Dp in males is also quite similar to E. concinnus and E. trejaensis sp. nov. and very different from E. niciensis stat. nov. and E. stefaniae sp. nov. As for Pe-et, E. latinus sp. nov. has the largest percentage of et = 5, i.e., 17.28%, vs. percentages ranging from 5.93% to 10.69%.

Euscorpius latinus sp. nov. is the southernmost species of the E. concinnus group and its known distribution includes central southern Lazio, on the left bank of the Tiber River, and north-western Molise. Regarding the latter location, this is the first time that a member of the E. concinnus group is reported from this region. This could be due to an accidental introduction, but we cannot dismiss the possibility of this area belonging to the natural distributional range of the species. The Apennines in this area are less elevated and more fragmented, and this may have facilitated the colonisation of that region. It remains to be seen if this species continues its distribution to the left of the Tiber River until it reaches Umbria, or if the latter region is inhabited by another species of the E concinnus group, as well as whether the species is also present in Campania.

Euscorpius latinus sp. nov. was found from almost the sea level (e.g., in Castel Fusano, near Ostia (RM)), up to ~ 900 m a.s.l. on the Lucretili Mountains. It was always found in woodlands, mostly mesophilic, but also hygrophilous. It is evident that the species prefers very humid habitats and microhabitats. In these environments, E. latinus sp. nov. behaves as a lapidicolous and corticolous species, since it mainly occurs under stones, but also under branches, trunks, and bark, often rotting, as well as inside pine cones. Euscorpius latinus sp. nov. has not been found in sympatry with other species of scorpions, but it cannot be excluded that rare encounters may occur with T. flavicaudis or Euscorpius italicus (Herbst, 1800) which prefer more rural and less humid habitats than completely natural and very humid ones as E. latinus sp. nov.

Holotype : ♂, Italy, Veneto, Euganean Hills, August 2017, leg. S. Tropea, (GTC).

Paratypes: Italy: Veneto: Euganean Hills, August 2017, leg. S. Tropea, 9 ♂♂, 12 ♀♀ paratypes (GTC); same data but August 2013, leg. S. Tropea, 2 ♂♂ imm., 3 ♀♀ (which 1 imm.) paratypes (GTC).

(not included in type series). Italy, Veneto: Euganean Hills, 18 August 2012, leg. M. Fontana, 2 ♂♂ imm., 1 ♀ imm. (GTC).

The specific epithet is in homage to the sister of the first author, Stefania Tropea, for her kind support and enthusiasm shown in several field trips.

Italy: Veneto (Fig. 32).

Medium Euscorpius species, total length 27–33 mm. The adults are usually blackish coloured, with more or less marked reddish brown marbling, in the less granulated areas, and chelae with fingers ranging from pale yellowish brown to dark reddish brown with blackish reticulation. Some specimens may be reddish brown. The number of trichobothria on the pedipalp manus ventral surface is four (V_1–3 + Et₁). Trichobothria est and dsb on fixed finger are respectively located distally and proximally to the notch of the fixed finger. The number of trichobothria on the pedipalp patella ventral surface usually is eight (in 81.67% of the pedipalps examined). The number of trichobothria on pedipalp patella external surface usually is: eb = 4, eb_a = 4, esb = 2, em = 4, est = 4, et = 6. The pectinal teeth number in males usually is nine (in 92.86% of the pectines examined) and in females mostly seven (seven or eight). Dorsal patellar spur well developed. Femur usually slightly shorter than patella. Carapace approximately as long as wide, but it can be both slightly longer and shorter. Carinae V₁ follows an external direction to the trichobothria Et₁, without forming a Y-shape. Spinules on legs ending with a Y-shape. Ventrolateral and ventromedian carina on metasomal segment V formed by small serrulated granules.

The variation observed in 30 examined specimens (14 ♂♂ and 16 ♀♀) is given below.

Pectinal teeth in males (n = 28): 9/9 (12), 9/10 (1), 10/9 (1); in total, 9 in 92.86% (26/28) and 10 in 7.14% (2/28); mean = 9.07, SD = 0.26.

Pectinal teeth in females (n = 32): 7/7 (11), 8/7 (2), 8/8 (3); in total, 7 in 75% (24/32) and 8 in 25% (8/32); mean = 7.25, SD = 0.44.

Pedipalp patella trichobothria Pv (n = 60): 7/7 (2), 7/8 (2), 8/6 (1), 8/7 (2), 8/8 (21), 8/9 (1), 9/8 (1); in total, 7 in 13.33% (8/60), 8 in 81.67% (49/60) and 9 in 3.33% (2/60); mean = 7.90, SD = 0.40.

Pedipalp patella trichobothria Pe (n = 60): et = 5/5 (2), 6/1 (1), 6/5 (2), 6/6 (23), 6/7 (1), 7/7 (1); in total, 5 in 10% (6/60), 6 in 83.33% (50/60) and 7 in 5% (3/60), mean = 5.95, SD = 0.39;

est = 2/4 (1), 3/2 (1), 3/3 (1), 3/4 (1), 2 (4/3), 4/4 (24); em = 3/3 (1), 3/4 (1), 4/3 (1), 4/4 (27); esb = 2/2 (30); eb_a = 3/3 (1), 4/3 (1), 4/4 (28); eb = 4/3 (1), 4/4 (27), 4/5 (1), 5/4 (1).

Colouration. A general black base colour with more or less marked paler marbling or reticulation, reddish brown, in the less granulated areas, especially of the metasoma, legs, pedipalps and chelicerae; telson mostly black with two ventrally longitudinal pale brown stripes and one for each side, with yellowish pale brown sting; pale brown chelicerae with dark brown reticulation; chelae with fingers ranging from pale yellowish brown to dark reddish brown with blackish reticulation; legs with almost completely yellowish tarsus, the basitarsus and tibia are especially internally yellowish with dark blackish brown marbling, the patella and femur are mostly dark with paler marbling; pectines and genital operculum yellowish; sternites range from almost completely black to the most distal to yellowish marbled brown of the most proximal.

Carapace. Almost completely covered by a dense granulation; anterior edge is mostly straight and granulate; deep posterior lateral furrows; two pairs of lateral eyes, and a pair of median eyes; length from centre of median eyes to anterior margin is 44% of carapace length.

Mesosoma. The tergites are thickly granulated; sternites glossy and finely punctuated; small spiracles inclined to ~ 45° downward towards outside.

Metasoma. Dorsal carinae on segments I–IV with spaced granules; ventrolateral carinae on segment I absent, on segment II and III smooth or obsolete, on segments IV rouge, on segment V slightly serrulated granules are present; ventromedian carinae absent on segment I–IV, on segment V it consists of small, slightly serrulated granules; intercarinal surfaces are mostly finely granulated with some area, especially those of paler colour, smooth.

Telson. Vesicle mostly smooth, with ventral setae of different size, especially near the vesicle/aculeus juncture.

Pectines. Teeth number 9/9; middle lamellae number 6/5; several microsetae on proximal area of teeth, marginal lamellae, and middle lamellae.

Genital operculum. The genital operculum is formed by two longitudinally devised subtriangular sclerites with genital papillae protruding.

Sternum. Pentagonal shape, type 2; slightly wider than long, with a deep posterior emargination.

Pedipalps. Coxa and trochanter with tuberculated carinae. Femur: dorsal internal and external and ventral internal carinae tuberculated; irregular ventral external carinae formed by tubercles just on 1/3 or 1/4 of femur length; external median carinae formed by lightly serrulated tubercles; anterior median carinae formed by some spaced conical tubercles with three macrosetae; intercarinal spaces granulated. Patella: dorsal and ventral internal carinae tuberculated; ventral external carinae crenulated; dorsal external carinae slightly crenulated to rough; intercarinal surfaces finely granulated, especially on the dark reticulations near the carinae. Dorsal patellar spur well developed. Chela: chelal carina D₁ is distinct, strong, dark and smooth with a few tubercles proximally; D₄ is rounded with a few spaced granules; V₁ is distinct, strong, dark, from rough to smooth, following an external direction to the trichobothria Et₁; V₃ is rounded with scattered granules; external carina granulated; intercarinal tegument granulated; the fixed and movable fingers with little marked notch and lobe, respectively.

Finger dentition. In the most distal part is present a DD on the tip; MD is formed by very small denticles closely spaced forming an approximately straight line, discontinued at level of the OD; fixed finger has 6/6 OD and 11/12 ID; movable finger has 8/8 OD and 16/16 ID.

Trichobothria. Chela: trichobothria on the pedipalp manus ventral surface V = 3/3 (V_1–3) + Et₁ = 1/1; trichobothrium V₄ situated on the external surface of the chela carina near the carina V₁; trichobothrium ratio of et-est/est-dsb is ~ 1. Patella: Pv = 8/8; et = 6/6, est = 4/4, em = 4/4, esb = 2/2, eb_a = 4/4, eb = 4/4. Femur: trichobothrium d is slightly proximal to i, while trichobothrium e is well distal to both d and i, and situated on dorsal surface on dorsal external carina.

Legs. Two pedal spurs present; no tarsal spur; ventral row of tarsus with a total of 9/12 spinules on leg III, of increasing size from proximal to distal, ending with a Y-shape; three main flanking tarsal setae present. Tubercles present on ventral and dorsal surface of all leg femora.

Chelicerae. Typical of the genus Euscorpius.

Type A. It has a well-developed lamina tapered distally; well-developed basal constriction present; truncal flexure present; median projection with lde, ldi, and lb; internal projection distally with seven or eight tines in its crown. The number and the shape of tines of the crown varied between specimens and between the right and the left hemispermatophores.

Euscorpius stefaniae sp. nov. is the only species of E. concinnus group occurring in northeastern Italy. In fact, to the east of this species’ range, the genus Euscorpius s. str. is mostly represented by E. tergestinus, the most phylogenetically closely related species to E. concinnus group. This might suggest that E. stefaniae sp. nov. could be the most basal species of the latter species group, given that the dispersal and speciation of the genus Euscorpius s. str. seems to have proceeded in the direction from east to west. The dispersal and speciation probably continued westwards, following the Prealps and then the Apennines toward the south, which were the only possible dispersal routes since the relatively recent Padan Plain did not exist at that time. Euscorpius stefaniae sp. nov. could be a relict species, and the others species of the E. concinnus group speciated and colonised new areas approximately at the same period, but at a later time than E. stefaniae sp. nov., after the extinction of the ancestral population from most areas, as suggested by the 16S phylogeny (not shown here). However, in the concatenated tree inferred with 16S + COI markers, the most basal species, placed after E. tergestinus, is E. concinnus, with E. stefaniae sp. nov. in the apical position. This could be explained by the extinction of all ancestral populations in the north, and then the subsequent dispersal and speciation from areas, for example, of Tuscany. Euscorpius stefaniae sp. nov. is well separated from the other species of E. concinnus group with a divergence in 16S of 3.1%–4.2%, almost equal to that between E. tergestinus and E. concinnus. Morphologically, like the remaining species of the E. concinnus group and the numerous cryptic species complexes described in recent years, E. stefaniae sp. nov. is difficult to distinguish without knowing its origin and having a large sample size. However, it has morphological characters that show a good separation from other related species: E. stefaniae sp. nov. has the highest mean Dp in males (9.07) and the highest percentage of Dp = 9 (92.86%). The related species, on average, range from 8.05 to 8.25 except E. niciensis stat. nov., which has an average of 8.72, and Dp = 9 ranging from 10.46% to 19.64%, except E. niciensis stat. nov. which has 60.26%, a much lower value. Also, the average is higher in females compared to the other E. concinnus group species, but not significantly. Another interesting value in this species is Pv = 8 in 81.67%. In fact, although considered a typical value for the E. concinnus group, this species has the higher percentage with this number than the other species which have values ranging from 25% to 65%.

The Euganean Hills are a group of hilly reliefs of volcanic origin with a height ranging from ~ 200–600 m, which rises almost isolated to the southwest of Padua. The climate and microclimates on the Euganean Hills can vary greatly depending on the area. They can be mainly divided into sub-Mediterranean, typical of the south-facing slopes, and sub-mountain typical of the north-facing slopes. Depending on the slope and area, the woods can be quite humid. The specimens were found mostly under stones in the less humid areas and mostly under bark in the more humid areas.

Holotype : ♂, Italy, Latium, near Calcata (VT), Treja’s valley, 42.21953°N, 12.4175°E, 21 June 2020, leg. G. Tropea, (GTC 1184).

Paratypes: Italy: Latium: near Calcata (VT), Treja’s valley, 42.21953°N, 12.4175°E, 21 June 2020, leg. G. Tropea, 4 ♀♀ (GTC); near Calcata (VT), Treja’s valley, 42.2080833°N, 12.4141667°E, 13 June 2009, leg. G. Tropea, S. Tropea, 3 ♀♀ (GTC); near Calcata (VT), Treja’s valley, 28 July 2009, leg. G. Tropea, 2 ♂♂, 2 ♀♀ (GTC); same data but 2 April 2012, leg. G. Tropea, 3 ♀♀ (GTC); same data but 42.21413°N, 12.41629°E, 114 m, 6 May 2014, leg. G. Tropea, 3 ♂♂, 9 ♀♀ (GTC 498–508, 851); same data but 42.21930°N, 12.418°E – 42.2188889°N, 12.4154°E, between the 100 e i 150 m, 8 April 2018, leg. G. Tropea, 7 ♀♀ (GTC 1092–1098); Rio Fiume, Monti della Tolfa, 112 m, 42.07565°N, 11.96410°E, 11 May 2014, leg. G. Tropea, 5 ♂♂, 12 ♀♀ (GTC 509–525); Rio Fiume, Monti della Tolfa, 9 April 2012, leg. G. Tropea, 1 ♂, 3 ♀♀ (GTC 128–131).

(not included in type series). Italy: Latium: near Calcata (VT), Treja Valley, 42.21953°N, 12.4175°E, 21 June 2020, leg. G. Tropea, 2 ♀♀, of which one subadult (GTC); Lago di Bracciano, Oriolo Romano (VT), 491 m, 6 March 2013, 3 ♂♂ (CNBFVR); VT, Lago di Vico, loc. Monte Venere, 701 m, 6 March 2013, 7 ♂♂, 7 ♀♀ (CNBFVR); Monti Cimini, Monte Venere verso E Cerreta 560–580 m, 24 July-23 August 1985, leg. S. Pedullà, M. Rellori, 6 ♂♂ (MZUR 92–95, 98, 99); near Calcata (VT), Treja’s valley, 28 July 2009, G. Tropea, 6 ♂♂, 2 ♀♀ (NCS); same data but 2 April 2012, G. Tropea, 1 ♂ (NCS); Oriolo Romano, 1 May 2010, G. Tropea, 1 ♂, 2 ♀♀ (NCS); Canale Monterano (TV), 22 May 2010, G. Tropea, 4 ♀♀ (NCS); Rio Fiume, Monti della Tolfa, 9 April 2012, G. Tropea, 6 ♂♂, 7 ♀♀ (NCS); same data but 22 May 2010, 4 ♀♀ (NCS); Gorge of the Biedano, Barbarano Romano (TV), 27 March 2010, G. Tropea, 1 ♂, 1 ♀ (NCS); Castel Giuliano (RM), 42.03381°N, 12.13032°E, 10 April 2010, G. Tropea, 1 ♂, 1 ♀ (NCS).

The specific epithet is derived from Treja, the river that flows in the homonymous valley where the first specimens of E. trejaensis sp. nov. were collected.

Italy: Latium (right side of the Tiber River; Fig. 32).

A small Euscorpius species, total length 24–28 mm. Colour of adults mostly dark brown with darker marbling on most of the body, including chelicerae. The number of trichobothria on the pedipalp manus ventral surface is four (V_1–3 + Et₁). Trichobothria est and dsb on fixed finger are respectively located distally and proximally to the notch of the fixed finger. The number of trichobothria on the pedipalp patella ventral surface is usually seven and eight (seven in 34.07% of the pedipalps examined). The number of trichobothria on pedipalp patella external surface is usually: eb = 4, eb_a = 4, esb = 2, em = 4, est = 4, et = 6. Trichobothrium i of the femur is slightly proximal to or at the same level of d. The pectinal teeth number in males usually is eight (seven to nine) and in females usually is seven (six to eight). Dorsal patellar spur well developed. Femur is slightly shorter than the patella. Carapace approximately as long as wide, but it tends to be shorter than long in the females. Carinae V₁ follows an external direction to the trichobothria Et₁, without forming a Y-shape. Spinules on legs ending with a Y-shape. Ventrolateral and ventromedian carina on metasomal segment V well formed by small, spaced, slightly serrulated granules.

The variation observed in 113 examined specimens (43 ♂♂ and 70 ♀♀) is given below (left/right asymmetry not specified).

Pectinal teeth in males (n = 86): 7/8 (7); 8/8 (28), 8/9 (5), 8/10 (1), 9/9 (2); in total, 7 in 8.14% (7), 8 in 80.23% (69), 9 in 10.46% (9) and 10 in 1.16% (1); mean = 8.05, SD = 0.48.

Pectinal teeth in females (n = 137): 6/6 (9), 6/7 (11), 7/7 (41), 7/8 (5), 8/? (1), 8/8 (1), 9/8 (1); in total, 6 in 21.17% (29), 7 in 71.53% (98), 8 in 6.57% (9), 9 in 0.73% (1); mean = 6.87, SD = 0.54.

Pedipalp patella trichobothria Pv (n = 226): 6/6 (1), 6/7 (4), 7/7 (22), 7/8 (29), 8/8 (52), 9/8 (3); in total, 6 in 2.65% (6), 7 in 34.07% (77), 8 in 61.95% (140), and 9 in 1.33% (3); mean = 7.62, SD = 0.56.

Pedipalp patella trichobothria Pe (n = 159): et = 5/4 (2), 5/5 (3), 4/6 (1), 5/6 (9), 6/? (1), 6/6 (60), 7/6 (1), 7/7 (3); in total, 4 in 1.89% (3), 5 in 10.69% (17), 6 in 83.02% (132) and 7 in 4.40% (7); mean = 5.90, SD = 0.47;

est = 3/3 (1), 4/? (1), 4/3 (2), 4/4 (79), 5/4 (1); em = 3/? (1), 3/3 (1), 3/4 (10), 4/4 (71), 5/4 (1); esb = 2/? (1), 1/2 (2), 2/2 (81); eb_a = 3/3 (1), 3/4 (6), 4/? (1), 4/4 (74), 4/5 (2); eb = 3/4 (1), 4/? (1), 4/4 (82).

Colouration. A general dark brown base colour with more or less marked paler marbling or reticulation, reddish brown, in the less granulated areas, especially of the metasoma, legs, pedipalps and chelicerae; telson mostly dark brown with two ventrally longitudinal pale brown stripes and one for each side, with reddish brown distal part of the sting; ivory chelicerae with dark brown reticulation; chelae with fingers ranging from pale yellowish brown to dark reddish brown with dark blackish brown reticulation; legs with almost completely ivory tarsus, the basitarsus and tibia are mostly ivory, but with dark blackish brown marbling externally, almost ivory internally, the patella and femur are mostly dark with paler marbling externally, and mostly ivory internally; pectines and genital operculum whitish ivory; sternites range from almost completely black with pale spot on the most distal to very pale brownish at the most proximal.

Carapace. Almost completely covered by a dense fine granulation; anterior edge is granulate; deep posterior lateral furrows; two pairs of lateral eyes, and a pair of median eyes; length from centre of median eyes to anterior margin is 40.98% of carapace length.

Mesosoma. The tergites are densely covered with a fine granulation; sternites glossy and finely punctuated; small spiracles inclined to ~ 40° downward towards outside.

Metasoma. Dorsal carinae on segments I–IV with spaced granules; ventrolateral carinae on segment I absent, on segment II and III smooth or obsolete, on segments IV, little marked with some small and spaced granule, with small slightly serrulated granules on segment V; ventromedian carinae absent on segment I–IV, on segment V it consists of small, slightly serrulated granules; dorsal and lateral intercarinal surfaces on segments I–IV are mostly finely granulated, especially on dark marbling, while the ventral surfaces are mostly smooth, the V segment is mostly finely granulated.

Telson. Vesicle with a few small granules, with ventral setae of different size, especially near the vesicle/aculeus juncture.

Pectines. Teeth number 8/8; middle lamellae number 5/5; several microsetae on proximal area of teeth, marginal lamellae, and middle lamellae.

Genital operculum. The genital operculum is formed by two longitudinally devised subtriangular sclerites with genital papillae protruding.

Sternum. Pentagonal shape, type 2; slightly wider than long, with a deep posterior emargination.

Pedipalps. Coxa and trochanter with tuberculated carinae. Femur: dorsal internal and external and ventral internal carinae tuberculated; irregular ventral external carinae formed by tubercles only on 1/3 or 1/2 of femur length; external median carinae formed by lightly serrulated tubercles; anterior median carinae formed by some spaced conical tubercles with three macrosetae; intercarinal spaces granulated. Patella: dorsal and ventral internal carinae tuberculated; ventral external carinae crenulated; dorsal external carinae slightly crenulated; intercarinal surfaces finely granulated, especially on the dark reticulations near the carinae. Dorsal patellar spur well developed. Chela: chelal carina D₁ is distinct, strong, dark, and from smooth to slightly crenulated with a few tubercles proximally; D₄ is dark with flat joined tubercles; V₁ is distinct, strong, dark, from rough to crenulated, following an external direction to the trichobothria Et₁; V₃ is rounded with scattered granules; external carina granulated; intercarinal tegument granulated; the fixed and movable fingers with small, marked notch and lobe, respectively.

Finger dentition. In the distalmost part a DD is present on the tip; MD is formed by very small denticles closely spaced, forming an approximately straight line, discontinued at level of the OD; fixed finger has 6/6 OD and 10/10 ID; movable finger has 8/8 OD and 13/11 ID.

Trichobothria. Chela: trichobothria on the pedipalp manus ventral surface V = 3/3 (V_1–3) + Et₁ = 1/1; trichobothrium V₄ situated on the external surface of the chela carina near the carina V₁; trichobothrium ratio of et-est/est-dsb is ~ 1.43 and 1.25. Patella: Pv = 7/7; et = 5/6, est = 4/4, em = 4/4, esb = 2/2, eb_a = 4/4, eb = 4/4. Femur: trichobothrium d is slightly proximal to i, while trichobothrium e is well distal to both d and i, and situated on dorsal surface on dorsal external carina.

Legs. Two pedal spurs present; no tarsal spur; ventral row of tarsus with a total of 10/13 spinules on leg III, of increasing size from proximal to distal, ending with two spinules to form a Y-shape; three main flanking tarsal setae present. Tubercles present on ventral and dorsal surface of all leg femora.

Chelicerae. Typical of the genus Euscorpius.

Type A. It has a well-developed lamina tapered distally; well-developed basal constriction present; truncal flexure present; median projection with lde, ldi, and lb; internal projection distally with 5–7 tines in its crown. The number and the shape of tines of the crown varied between specimens and between the right and the left hemispermatophores.

Euscorpius trejaensis sp. nov. is geographically the closest species to E. latinus sp. nov., also part of the E. concinnus group, which seem to be divided from each other by the Tiber River. As mentioned above, this geographical proximity does not seem to result in a particular genetic relatedness. Indeed, according to the concatenated phylogenetic tree 16S + COI, E. trejaensis sp. nov. is paired with E. stefaniae sp. nov., with E. niciensis stat. nov. basal to them and between E. latinus sp. nov. and them. Regarding the divergence in 16S, between E. trejaensis sp. nov. and E. latinus sp. nov., it ranges from 2.7% to 3.1%, 3.1% with E. stefaniae sp. nov., and 2.7% with E. concinnus and E. niciensis stat. nov. Morphologically, like the other species of the E. concinnus group and the many cryptic species complex that have been described in recent years, E. trejaensis sp. nov. is difficult to distinguish without knowing its origin and having a good sampling size. As for the trichobothrial Pv values, we see that E. trejaensis, together with E. latinus, has the lowest average of Pv, ~ 7.60, having the percentage of Pv = 7 a little lower than in E. latinus sp. nov. (34.07% against 39.68%), but much higher than the other species treated here (2.78–13.33%); it has a percentage of Pv = 8 similar to E. concinnus and E. latinus sp. nov. (60.32–65.25%), much higher than E. niciensis stat. nov. (25% vs. 61.95%) and lower than E. stefaniae sp. nov. (81.67%). As for the Dp in males, E. trejaensis sp. nov. has the lowest average, the highest percentage of Dp = 8 and the lowest percentage of Dp = 9. These values are very different from those of E. niciensis stat. nov. and E. stefaniae sp. nov., and more similar to those of E. concinnus and E. trejaensis sp. nov. The Dp in females also reflects the same trend, albeit to a lesser extent. In fact, E. trejaensis sp. nov. has the lowest average and the highest percentage of Dp = 7 and 6, and the lowest percentage of Dp = 8.

The distribution of Euscorpius trejaensis sp. nov. affects the central-north western part of Lazio, on the right side of the Tiber River. However, it must be ascertained whether its diffusion continues northward into Tuscany and Umbria. Euscorpius. trejaensis sp. nov. was found from 100 m a.s.l. on the Tolfa Mountains to 700 m a.s.l. on Mount Venere. This lower altitude is probably caused by the fact that this area of Lazio has no particularly high mountain formations, but mostly hills and low mountains. Euscorpius trejaensis sp. nov. has always been found in natural areas, mostly in mesophilic forests, often with nearby streams, or in any case in very humid microhabitats. It showed mostly corticolous but also lapidicolous tendencies, having been found especially under the bark or cracks of fallen and rotting branches and trunks, or very damp, but also under stones, especially where there were few or no adequate branches. Euscorpius trejaensis sp. nov. was found a few centimetres from E. italicus once in the type locality; however, despite having examined the areas several times over the years, E. italicus has no longer been found. Probably the latter prefer rural and less humid areas, unlike E. trejaensis sp. nov., so their meeting is infrequent.

Euscorpius trejaensis sp. nov., like most species of Euscorpius, mate in spring and summer. The male grabs the female’s chelae and is in a constant state of alert and distrust (Fig. 24); the male stings the female between claw and patella of the pedipalp (Figs 25, 26), after which the female become calmer and cooperative. Thus begins a push and pull similar to a dance, but without the typical kiss of the scorpion (i.e., holding with chelicerae) observed in other species of scorpions (such as those belonging to the genus Heterometrus Ehrenberg, 1828), until the male finds a suitable surface to place the spermatophore and pulls the female until she goes over it, and the spermatophore fits into the genital operculum of female. Births usually take place in the summer of the following year, mostly in the months of July and August.

Holotype : by C.L. Koch (1841), France, from the region/zone of Nice, is lost.

Neotype : ♂, France, Col de Braus (Nizza), 22 August 1975, leg. A. Valle, (MSNB 10234), here designated according to ICZN Article 75 as it is required for the purposes of clarifying the taxonomic status and type locality of a specific taxon.

France: Same data as neotype but 4 ♂♂, 8 ♀♀ (MSNB 10232, 10233, 1035, 10605–10613); Colle dei Signori (Alpi Liguri), 2100 m, 1 August 1966, leg. A. Vigna, 1 ♂, 1 ♀ (MSNB 7375, 7376); Curbans (04), 20 August 2010, leg. E. Iorio, 1 ♂ (GTC); Entrevaux, 27 August 2018, leg. G. Ourliac, 2 ♂♂ (GTC); Gorges Daluis, 27 August 2018, leg. G. Ourliac, 3 ♂♂, 1 ♀♀ (GTC); Guillaumes, 25–27 August 2018, leg. G. Ourliac, 6 ♂♂, 2 ♀♀ (GTC); Guillaumes (06), 11 August 2018, leg. G. Ourliac, 1 ♂ (GTC); Meounes, Pes Montrieux, [Méounes-lès-Montrieux], 17 February 1973, leg. R. Bianchi et C. Fenaroli, 1 ♂ (MSNB 11354); Montrauraux (83), ZE1819, cheraie pierres, 19 May 2013, leg. E. Iorio, 1 ♀ (GTC); prov. Reotier (05), ZE RTE P3, 27 July 2010, leg. E. Iorio, 1 ♀ (GTC); St. Jeannet (6), 20 July 2018, 1 ♀ (GTC); Italy: Alassio (SAVONA), Valle ovest della Solva, 19 July, 1958, A. Valle, 7 ♀♀ (MSNB 832–835, 837–839); Andagna, Molini di Triora (IM), 30 May 1973, leg. R. Bianchi, 1 ♀ (MSNB 9823); Bardineto (SV), 26 August 1967, leg. A. Vigna, 1 ♂ (MSNB 7371); Castellaro (IM), 8 October 1969, leg. G.P. Rallo, 1 ♂ (MSNB 8032); Castellaro (IM), 8 October 1969, leg. Rallo, 1 ♂ (MSNB 8030); Celle Ligure (SV), 9 July 1956, leg. A Valle, 2 ♀♀ (MSNB 14, 16); Cesio (IM), 29 May 1973, leg. R. Bianchi, 1 ♂, 7 ♀♀ (MSNB 9802–9808, 9890); Chiusanico (IM), surroundings Di Torria, 7 March 1976, leg. M. Bologna, 1 ♂ (MSNB 10589); Chiusanico (IM), leg. 07 March 1976, leg. M. Bologna, 1 ♀ (MSNB 10588); Cosio d’Arroscia (IM), 27 June 1971, leg. R. Bianchi, 3 ♂♂, 5 ♀♀ (MSNB 8633–8641); Molini di Triora (IM), 30 May 1973, leg. R. Bianchi, 2 ♂♂, 1 ♀ (MSNB 9736, 9737, 9812); Monte Bardellini, (IM), 28 March 1970, leg. M. Bologna, 1 ♂, 1 ♀ (MSNB 9996, 9997); Sanremo (IM), 9 October 1969, leg. G.P. Rallo, 2 ♂♂, 1 ♀ (MSNB 8035–8037); Taggia (IM), 7 October 1969, leg. G.P. Rallo, 3 ♂♂, 1 ♀ (MSNB 8026–8028, 8034); Taggia (IM), 30 March 1970, leg. G.P. Rallo, 2 ♂♂, 3 ♀♀ (MSNB 8488–8492); Valdieri (CN), Andonno, 720 m, 26 August 1964, leg. A. Vigna, 1 ♀ (MSNB 4600); Ormea (CN), Ponte di Nava, 27 June 1971, leg. R. Bianchi, 2 ♂♂, 3 ♀♀ (MSNB 8642–8646).

France and Italy (Fig. 32).

Medium Euscorpius species, total length 27–45 mm. Colour in adults usually brown to dark brown with darker brownish red pedipalps, and legs, chelicerae, and telson yellow or yellowish, but with sometimes legs and especially the telson brownish, with marbling especially on chelicerae, carapace, mesosoma, and metasoma. The number of trichobothria on the pedipalp manus ventral surface is four (V_1–3 + Et₁). Trichobothria est and dsb on fixed finger are respectively located distally and proximally to the notch of the fixed finger, although they can sometimes be only slightly distal or proximal. The number of trichobothria on the pedipalp patella ventral surface is usually nine and eight (mostly nine). The number of trichobothria on pedipalp patella external surface is usually: eb = 4, eb_a = 4, esb = 2, em = 4, est = 4, et = 6. The pectinal teeth number in males is usually nine and eight (nine in 60.26% and eight in 32.05%) and in females seven and eight (seven in 61.46% and eight in 33.33%). Dorsal patellar spur well developed. Femur approximately as long as patella but usually is slightly shorter. Carapace approximately as long as wide, but it usually is slightly wider than long. Carinae V₁ follows an external direction to the trichobothria Et₁, without forming a Y-shape. Spinules on legs ending with a Y-shape. Ventrolateral and ventromedian carina on metasomal segment V well formed by small serrulated granules.

The variation observed in 90 examined specimens (39 ♂♂ and 51 ♀♀) is given below.

Pectinal teeth in males (n = 78): 7/8 (1), 8/8 (8), 8/9 (8), 9/9 (18), 10/9 (3), 10/10 (1); in total, 7 in 1.28% (1), 8 in 32.05% (25), 9 in 60.26% (47), and 10 in 2.56% (5); mean = 8.72, SD = 0.60.

Pectinal teeth in females (n = 102): ?/? (3), 6/6 (1), 7/6 (2), 7/7 (24), 7/8 (9), 8/8 (11), 8/9 (1); in total, 6 in 4.17% (4), 7 in 61.46% (59) and 8 in 33.33% (32), 9 in 1.04% (1); mean = 7.31, SD = 0.57.

Pedipalp patella trichobothria Pv (n = 180): 7/7 (1), 7/8 (2), 8/8 (13), 8/9 (17), 9/7 (1), 9/9 (51), 10/9 (4), 10/10 (1); in total, 7 in 2.78% (5), 8 in 25% (45), 9 in 68.89% (124), and 10 in 3.33% (6); mean = 8.73, SD = 0.57.

Pedipalp patella trichobothria Pe (n = 180): et = 5/5 (4), 5/6 (3), 6/6 (68), 6/7 (6), 7/5 (1), 7/6 (2), 7/7 (6); in total, 5 in 6.67% (12), 6 in 81.67% (147) and 7 in 11.67% (21); mean = 6.05, SD = 0.43;

est = 3/4 (1), 4/4 (89); em = 3/3 (1), 4/3 (2), 4/4 (86), 5/4 (1); esb = 2/2 (90); eb_a = 4/4 (90); eb = 4/4 (90).

(MSNB 10234). Colouration. A general reddish brown base colour, with blackish marbling or reticulation especially on the metasoma, mesosoma, carapace, pedipalp femur, patella, and chelicerae; telson mostly black with two ventrally longitudinal pale brown stripes and one for each side, with pale yellowish brown sting; pale brown chelicerae with dark brown reticulation; chelae dark reddish brown; legs orangish; pectines, genital operculum, and sternites yellowish.

Carapace. Almost completely covered by dense fine granules, especially on the dark marbling. The granules in the lateral anterior part are larger; the anterior edge is straight and slightly granulate; deep posterior lateral furrows; two pairs of lateral eyes, and a pair of median eyes; length from centre of median eyes to anterior margin is 43.75% of carapace length.

Mesosoma. Mostly of the tergites are very granulated, especially laterally; sternites glossy and punctuated; small spiracles inclined to ~ 45° downward towards outside.

Metasoma. Dorsal carinae on segments I–IV granulated; ventrolateral carinae on segment I absent, on segments II and III smooth or obsolete, on segment IV with some granules, on segment V well marked with small serrulated granules; ventromedian carinae absent on segments I–IV, on segment V it consists of small, serrulated granules; intercarinal surfaces on segments I–IV are from finely granulated (e.g., dorsally) to smooth (e.g., ventrally), segment V is mostly granulated.

Telson. Vesicle mostly smooth, with ventral setae of different size, especially near the vesicle/aculeus juncture.

Pectines. Teeth number 9/8; middle lamellae number 5/5; several microsetae on proximal area of teeth, marginal lamellae, and middle lamellae.

Genital operculum. The genital operculum is formed by two longitudinally divided subtriangular sclerites with genital papillae protruding.

Sternum. Pentagonal in shape, type 2; wider than long, with a deep posterior emargination.

Pedipalps. Coxa and trochanter with tuberculated carinae. Femur: dorsal internal and external and ventral internal carinae tuberculated; irregular ventral external carinae formed by tubercles just on 1/3 or 1/2 of femur length; external median carinae formed by lightly serrulated tubercles; anterior median carinae formed by some spaced conical tubercles with three macrosetae; intercarinal spaces granulated. Patella: dorsal and ventral internal carinae tuberculated; ventral external carinae crenulated; dorsal external carinae slightly crenulated to rough; intercarinal surfaces finely granulated, especially on the dark reticulations near the carinae. Dorsal patellar spur well developed. Chela: chelal carina D₁ is distinct, strong, dark and smooth with a few flat tubercles proximally; D₄ is rounded with a few spaced granules; V₁ is distinct, strong, dark, from rough to crenulated, following an external direction to the trichobothria Et₁; V₃ is rounded with scattered granules; external carina granulated; intercarinal tegument granulated; the fixed and movable fingers with little marked notch and lobe, respectively.

Finger dentition. In the most distal part is present a DD on the tip; MD is formed by very small denticles closely spaced forming an approximately straight line discontinued at level of the OD; fixed finger has 6/6 OD and 11/11 ID; movable finger has 8/7 OD and 13/13 ID.

Trichobothria. Chela: trichobothria on the pedipalp manus ventral surface V = 3/3 (V_1–3) + Et₁ = 1/1; trichobothrium V₄ is situated on the external surface of the chela, near the carina V₁ well-spaced from it; trichobothrium ratio et-est/est-dsb is 1.31/1.17. Trichobothrium dsb is located slightly proximal at the centre of the notch. Patella: Pv = 9/9; et = 6/6, est = 4/4, em = 4/4, esb = 2/2, eb_a = 4/4, eb = 4/4. Femur: trichobothrium d is slightly proximal, almost on the same level, to i, while trichobothrium e is well distal to both d and i, and situated on dorsal surface on dorsal external carina.

Legs. Two pedal spurs present; no tarsal spur; ventral row of tarsus with a total of eleven spinules, of increasing size from proximal to distal, ending with a Y-shape; three main flanking tarsal setae present. Tubercles present on ventral and dorsal surfaces of all leg femora, they are more marked and darker ventrally.

Chelicerae. Typical of the genus Euscorpius.

Type A. It has a well-developed lamina tapered distally; well-developed basal constriction present; truncal flexure present; median projection with lde, ldi, and lb, the latter with rounded tip; internal projection distally with 7–9 tines in its crown. The number and the shape of tines of the crown varied between specimens and between the right and the left hemispermatophores.

Euscorpius niciensis stat. nov. was described by C.L. Koch (1841) under the genus Scorpius from the region or zone of Nice, France. As explained by Tropea (2013, 2017), according to Koch the locality could be up to at least 50 km from Nice, so the exact type locality cannot be known. This species was described using only a few characters useful for identifying the species, and relying on a single specimen. In our study, several specimens from the surrounding areas of Nice and beyond were examined, and we found that those populations have significantly higher average and percentage values of Pv, Pe-et, and Dp than the closely related species, as can be seen in Tables 3 and 4. In fact, E. niciensis stat. nov. has an average Pv value of 8.73 with a percentage of 68.89% of Pv = 9, compared to an average ranging from 7.60 to 8.19 and a percentage of Pv = 9 ranging from 0% to 27.12% in the other species treated here. In addition, it is the only species (of the E. concinnus group) that, although with a limited percentage, showed a Pv = 10. The Pe-et percentages are also much higher than of other populations, with only some populations of E. concinnus approaching it. In fact, E. niciensis stat. nov. has a percentage et = 7 of 11.67%, compared to 1.23% of E. latinus sp. nov., 4.40% of E. trejaensis sp. nov., 5% of E. stefaniae sp. nov., and 9.32% of E. concinnus. To infer the phylogenetic trees, we have used only 16S (see Table 5). In the 16S+COI concatenated tree, it is placed between E. latinus sp. nov. and (E. stefaniae sp. nov. + E. trejaensis sp. nov.). Regarding the genetic divergence in 16S, E. niciensis stat. nov. is the most distant species from E. stefaniae sp. nov. with 3.8%, and 2.7% of divergence from all the other species, except E. latinus sp. nov. from Circeo, with which it has a divergence of 3.1%.

With these findings, the validity of E. niciensis stat. nov. is unquestionable, even if it is not excluded that further taxonomic divisions exist in it, as well as for E. concinnus, which need to be confirmed with further studies.