Monatractides (Monatractides) polypapillatus, Pešić, Vladimir & Smit, Harry, 2012

Pešić, Vladimir & Smit, Harry, 2012, Water mites of the genus Monatractides (Acari: Hydrachnidia, Torrenticolidae) from Australia, with descriptions of four new species, Zootaxa 3248, pp. 1-24 : 12-15

Monatractides (Monatractides) polypapillatus sp. nov.

( Figs. 6–7 , 14E–F, H )

Type material. Holotype male, dissected and slide mounted, Double Barrel Creek, Babinda, Queensland, Australia, 20.x.2005, 17º 20.852 S 145º 53.075 E (QM). Paratypes: 0/2/0, same data as holotype, one female dissected and slide mounted (QM); Queensland: Big Crystal Creek at Paradise Pool, Paloma Range NP, 18º 58.754 S 146º 15.231 E, 21.x.2005, 3/0/0 ( RMNH, 1/0/0 mounted); Hutchinson Creek S of Cape Tribulation, 15.x.2005, 16º 13.014 S 145º 25.431 E 2/1/0 ( RMNH); Northern Territory, Katherine River S of visitor center, Nitmiluk NP, 14º 19.472 S 132º 24.804 E, alt. 119 m asl, 02.x.2005 6/7/0 ( NTM).

Further records. Queensland: Whyanbeel Creek, N of Mossman, 15.x.2005, 16º 22.205S 145º 19.633E, 1/1/0; Wenlock River at crossing with Road to Iron Range NP, 06.xi.2000 0/1/0; Northern Terrıtory: Katherine River near visitor center, Katherine Gorge NP, 28.vii.1994 4/9/0 (2/2/0 mounted); South Alligator River, 11 km E of Gunlom, Kakadu NP, 26.vii.1994 0/1/0.

Diagnosis. Area of primary sclerotization of the dorsal plate with four dorsoglandularia; capitular bay slender (L/W ratio 2.8–3.0), the ventral surface of anterior part of Cx-1 with 7–12 pairs of knob-shaped protrusions, one pair at the apical tip of Cx-1 ( Fig. 6C ); suture line of Cx-4 partially distinct, directed posterolaterally; postgenital area large; excretory pore posterior to the line of primary sclerotization, Vgl-2 well posterior to excretory pore; distal margins of P-2 and -3 without denticles, P-4 with small denticle near the insertion of the ventral hairs; I-L-6 relatively slender (L/H ratio 2.8–3.0). Males: median suture line of Cx-2+3 relatively long.

Description. Male (holotype; in parentheses specimen from Katherine River near visitor center, Northern Territory, n = 1; in square parentheses specimen from Big Crystal Creek, Queensland, n = 1): Idiosoma (ventral view: Fig. 6B ) L 831 (764) [794], W 606 (563) [600]; dorsal shield ( Fig. 6A ) L 684 (638) [694], W 500 (468) [475], L/W ratio 1.37 (1.36) [1.46]; dorsal plate 638 (591) [650]; shoulder plate L 159–171 (144–151) [177–178], W 58–61 (52–56) [63], L/W ratio 2.74–2.8 (2.7–2.77) [2.81–1.83]; frontal plate L 127–128 (114) [128–131], W 61–66 (59) [59–61], L/W ratio 1.94–2.08 (1.9) [2.15–2.17]; shoulder/frontal plate L ratio 1.25–1.34 (1.26–1.32) [1.36–1.38]; dorsal and ventral shield with colour pattern as illustrated in Figs. 14E–F and 14H ; capitular bay L 141 (138) [131], W 47 (47) [47], L/W ratio 3.0 (2.94) [2.79]; Cx-1 total L 260 (244) [256], Cx-1 medial L 119 (106) [125], Cx-2+3 medial 117 (105) [119]; ratio Cx-1 L/Cx-2+3 medial L 2.2 (2.3) [2.15]; Cx-1 medial L/Cx-2+3 medial L 1.02 (1.01) [1.05]; genital field L/W 147 (138) [148]/128 (116) [121], L/W ratio 1.15 (1.19) [1.22]; ejaculatory complex ( Fig. 6E ) normal in shape, L 207 (189) [205]; distance genital field–excretory pore 181 (181) [156], genital field–caudal idiosoma margin 295 (273) [247]; capitulum ( Fig. 6H ) ventral L 202 (190) [193]; chelicera total L 225 (217) [211]; palp ( Figs. 6E–G ): total L 188 (182) [182], dL: P-1, 25 (23) [25]; P-2, 57 (56) [57]; P-3, 42 (39) [39]; P-4, 49 (49) [46]; P-5, 15 (15) [15]; P-2/P-4 ratio 1.16 (1.14)[1.24]; L I-4-6 ( Fig. 6I ): 107 (102) [103], 114 (105) [107], 111 (103) [108]; I-L-6 L/H 2.87 (2.88) [2.87].

Female (paratype; in parentheses specimen from Katherine River near visitor center, Northern Territory, n = 1): Idiosoma (ventral view: Fig. 7B ) L 909 (788), W 653 (575); dorsal shield ( Fig. 7A ) L 744 (681), W 553 (500), L/W ratio 1.35 (1.36); dorsal plate 703 (634); shoulder plate L 173–175 (156), W 63 (61), L/W ratio 2.75–2.8 (2.56); frontal plate L 130–131 (119), W 59–63 (58–63), L/W ratio 2.08–2.2 (1.9–2.05); shoulder/frontal plate L ratio 1.33–1.34 (1.31); dorsal and ventral shield with colour pattern as in male; capitular bay L 148 (134), W 49 (47), L/W ratio 3.02 (2.85); Cx-1 total L 284 (250), Cx-1 medial L 136 (116), Cx-2+3 medial 84 (88); ratio Cx-1 L/ Cx-2+3 medial L 3.38 (2.84); Cx-1 medial L/Cx-2+3 medial L 1.62 (1.32); genital field L/W 159 (153)/154 (147), L/W ratio 1.03 (1.04); egg maximum diameter L (191–192, n = 2); distance genital field–excretory pore 227 (170), genital field–caudal idiosoma margin 363 (281); capitulum ventral L 208; chelicera total L 248; palp ( Fig. 7D ): total L 203 (178), dL: P-1, 29 (23); P-2, 63 (56); P-3, 44 (36); P-4, 52 (48); P-5, 15 (15); P-2/P-4 ratio 1.21 (1.17); L I-4-6 ( Fig. 7E ): 109 (97), 115 (100), 111 (103); I-L-6 L/H 2.85 (3.03).

Discussion. Monatractides polypapillatus sp. nov. resembles M. australicus (see above), but can be distinguished in having a longer medial suture line of Cx-2+ 3 in male (L> 100µm), 7–12 pairs of knob-shaped protrusions at the ventral surface of anterior part of Cx-1 and the characteristic colour pattern on the dorsal and ventral shield. Furthermore, in M. polypapillatus sp. nov. the capitular rostrum is more elongated and I-L-6 is more slender (L/H ratio> 2.8).

The specimens from Northern Territory (Katherine River) are without colour pattern on the dorsal and ventral shield. In all other important diagnostic features these specimens are in good agreement with the type specimens from Queensland.

Etymology. Named after the presence of knob-shaped protrusions at the lateral margin of the capitular bay. Distribution. Australia: Queensland, Northern Territory (present study).

Figures

FIGURE 6 A – I. Monatractides polypapillatus sp. nov., male, Double Barrel Creek (Qld): A = dorsal shield; B = ventral shield; C = capitular bay; D = anterodorsal portion of ventral shield; E = ejaculatory complex; F = palp, lateral view; G = palp, medial view; H = capitulum and chelicera; I = I-L- 4 - 6. Scale bars = 100 μm.

FIGURE 7 A – E. Monatractides polypapillatus sp. nov., female, Double Barrel Creek (Qld): A = dorsal shield; B = ventral shield; C = anterodorsal portion of ventral shield; D = palp, lateral view; E = I-L- 5 - 6. Scale bars = 100 μm.

FIGURE 14 A – I. Photographs of dorsal and ventral shields. A – D Monatractides australicus (Cook, 1986): A—specimen from Double Barrel Creek, Qld (male, dorsal shield), B—specimen from Double Barrel Creek, Qld (female, dorsal shield), C - specimen from Swampy Plain River, NSW (female, dorsal shield), D—specimen from Big Crystal Crek, Qld (male, ventral shield); E – F, H Monatractides polypapillatus sp. nov.: E—specimen from Double Barrel Creek, Qld (male, dorsal shield), F—specimen from Big Crystal Creek, Qld (male, ventral shield), H—specimen from Double Barrel Creek, Qld (female, dorsal shield). G Monatractides ironicus sp. nov.: specimen from Gordon Creek (Qld) (male, dorsal shield). I Monatractides harveyi sp. nov.: specimen from Barramundie Creek (NT) (male, dorsal shield).