Torrenticola lukai, Pešić, Vladimir, Valdecasas, Antonio G. & García-Jimenez, Ricardo, 2012

Pešić, Vladimir, Valdecasas, Antonio G. & García-Jimenez, Ricardo, 2012, Simultaneous evidence for a new species of Torrenticola Piersig, 1896 (Acari, Hydrachnidia) from Montenegro, Zootaxa 3515, pp. 38-50 : 40-43

Torrenticola lukai sp. nov.

( Figs. 1–3 , 7A,C , 8A,C , 9A,D )

Torrenticola lundbladi Pešić, 2004 , nec K. Viets, 1930

Type material. Holotype male ( NHMB), dissected and slide mounted, Montenegro, stream Mrtvıca near village Velje Duboko (42°46'47''N, 19°16'56''E; 820 m a.s.l.), 13.viii.2010 . Paratypes: 9/4/0, same data as holotype, 2/2/0 (mounted); 4/1/0 in voucher collection for molecular study .

Further records. Montenegro: stream Mrtvica near village Mrtvo Duboko (42°43'N 19°21'E, 600 m a.s.l.), 11.vii.1999, Pešiċ “ Torrenticola lundbladi ” 2/0/0 (mounted) ; Komovi Mt., river Opasanica near Opasanica village (42°40'38''N, 19°32'40''E; 1130 m a.s.l.) 12.viii.1998, Pešiċ “ Torrenticola lundbladi ” 1/0/0 (mounted) ; ibid., 15.viii.1999, Pešiċ “ Torrenticola lundbladi ” 1/2/0 (mounted) ; stream Bistrica near Crkvine village (42°48'N, 19°27'E; 1122 m a.s.l.), 15.ix.2004 2/0/0 (mounted).

Diagnosis. Idiosoma large in size (L 850–1050 in males, 1000–1200 in females); shoulder platelets fused to dorsal plate, but suture line visible; area of primary sclerotization of the dorsal plate with two dorsoglandularia; posterior suture line of Cx-4 partly distinct; postgenital area large; excretory pore and Vgl–2 posterior to the line of primary sclerotization; distal margins of P-2 and -3 without denticles, ventral protuberance of P-4 unpaired, with one longer, and three shorter hairs; capitular rostrum relatively short and deep (L/H ratio 1.2–1.4). Male: median suture line of Cx-2+3 relatively long (140–160, L ratio Cx-1/Cx-2+3 2.1–2.5), genital field rectangular in shape.

Description. Male (holotype, in parentheses measurements of the paratypes, n = 2): Idiosoma (ventral view: Fig. 1B , 8A ) L 969 (881–1018), W 760 (681–775); dorsal shield ( Fig. 1A , 7A ) L 850 (738–838), W 630 (563–668), L/W ratio 1.35 (1.26–1.31); dorsal plate 791 (694–794); frontal platelets L 181–183 (159–187), W 76–77 (63–75), L/W ratio 2.38 (2.48–2.6); capitular bay L 156 (130–159); Cx-1 total L 366 (309–367), Cx-1 mL 209 (178–208), Cx-2+3 mL 145 (140–145); ratio Cx-1 L/Cx-2+3 mL 2.52 (2.2–2.53); Cx-1 mL/Cx-2+3 mL 1.44 (1.28–1.43); genital field L/W 168 (152–169)/140 (122–145), L/W ratio 1.2 (1.17–1.25); ejaculatory complex as in Figure 2C , L 206 (205–260); distance genital field–excretory pore 191 (175–222), genital field–caudal idiosoma margin 278 (275–319); capitulum ( Fıg. 2D–E , 9D ) vL 294 (268–300); chelicera total L 361 (329); palp ( Figs. 2A–B ): total L 350 (300–345), dL: P-1, 43 (38–42); P-2, 109 (95–109); P-3, 69 (60–67); P-4, 109 (88–105); P-5, 20 (19–22); P-2/P-4 1.0 (1.04–1.08).

Female (paratypes, n = 2): Idiosoma (ventral view: Fig. 3, BC) L 1075–1100, W 850–900; dorsal shield ( Fig. 8C ) L 916–988, W 715–725, L/W ratio 1.28–1.36; dorsal plate 853–913; frontal platelets L 190–203, W 78–92, L/ W ratio 2.07–2.52; capitular bay L 144–153; Cx-1 total L 370–383, Cx-1 mL 225–229, Cx-2+3 mL 45–52; ratio Cx-1 L/Cx-2+3 mL 7.37–8.2; Cx-1 mL/Cx-2+3 mL 4.4–5.0; genital field L/W 228–231/198–200, L/W ratio 1.14–1.17; distance genital field–excretory pore 269–284, genital field–caudal idiosoma margin 413–417; capitulum ( Fig. 9A ) vL 316; chelicera total L 375; palp: total L 350–370, dL: P-1, 44–49; P-2, 109–115; P-3, 68–72; P-4, 108–114; P-5, 20–21; P-2/P-4 ratio 1.01 (1.01).

Discussion. Pešiċ (2004) reported from northern Montenegro the presence of Torrenticola lundbladi ( K. Viets, 1930) , a species hitherto known only from Spain ( K. Viets 1930, Lundblad 1956). The specimens closely resemble the latter species due to the longer medial suture of Cx-2+ 3 in male, a similar shape of ejaculatory complex and the rectangular shape of the male genital field ( Pešiċ 2004). However, from a re-examination of the specimens in question and the study of newly collected material resulted fundamental differences, showing that populations from Montenegro, here described as T. lukai sp. nov., are not conspecific with T. lundbladi . Namely, as showed by Lundblad (1956), and confirmed by our new material from Spain, T. lundbladi clearly differs from the specimens from Montenegro in a longer and more slender capitular rostrum (compare Figs. 2D, E , 9A, D with 5D, F, 9B–C, E–F). Further differences include the indistinct posterior suture line of Cx- 4 in T. lundbladi .

Pešiċ et al. (2007) stated that the similar shape of ejaculatory complex and rectangular shape of the male genital field of the specimens from Montenegro indicate a close relationship to Torrenticola lesbica Di Sabatino & Gerecke, 2003 , described from the island Lesbos, Greece ( Di Sabatino et al. 2003) and later reported from the Eastern Black Sea coast of Turkey ( Pešiċ et al. 2007) and Macedonia ( Pešiċ et al. 2007). The latter species (in the following in the parentheses, data taken from Di Sabatino et al. 2003 and Pešiċ et al. 2007) can be distinguished from T. lukai sp. nov. in a shorter median suture line of Cx-2+ 3 in males (94–100, L ratio Cx-1/Cx-2+3 2.8–3.2), and a slightly less enlarged idiosoma in both sexes (750–850 in males, 850–950 in females).

Etymology. The species is named after Luka Pešiċ, an in 2012 two-year old son of the first author.

Habitat. Rhitrobiont; middle-order streams at elevation above 500 m a.s.l. ( Fig. 4 ), preferably in riffle areas.

Distribution. Montenegro.

Figures

FIGURE 4. Left—Map of Montenegro, showing location of four sampling sites. Sampling site number abbreviation is as follows: 1 — Mrtvica stream near village Velje Duboko, 2 — Mrtvica stream near village Mrtvo Duboko, 3 — Bistrica stream, 4 — Opasanica river. Right— Locus typicus (Mrtvica stream near village Velje Duboko, Montenegro) of Torrenticola lukai sp. nov. Photo: V. Pešić.

FIGURE 1 A – B. Torrenticola lukai sp. nov., male: A = dorsal shield; B = ventral shield. Scale bar = 100 µm.

FIGURE 2 A – G. Torrenticola lukai sp. nov., (A – F male, G female): A = palp, medial view, B = palp, lateral view; C = ejaculatory complex (non-mounted), D = capitulum and chelicera; E = capitulum, F – G = anterodorsal portion of ventral shield. Scale bars = 100 µm.

FIGURE 7 A – D. LSCM images of dorsal shield (A – B male, C – D female): A – C = Torrenticola lukai sp. nov. B – D = Torrenticola lundbladi (K. Viets, 1930). Scale bars = 100 µm.

FIGURE 8 A – D. LSCM images of ventral shield (A – B male, C – D female): A – C = Torrenticola lukai sp. nov. B – D = Torrenticola lundbladi (K. Viets, 1930). Scale bars = 100 µm.

FIGURE 9 A – F. LSCM images of gnathosoma: A, D Torrenticola lukai sp. nov. (A female, D male). B – C, E – F Torrenticola lundbladi (K. Viets, 1930) (B, E – F male, C female): A – C = capitulum and palps; D – E = capitulum, ventral view; E = capitulum, dorsal view. Scale bars = 50 µm.