Holoparasitus fanes, Witalinski, 2017

Witalinski, W., 2017, Two new species of Holoparasitus Oudemans, 1936 from Europe (Parasitiformes: Parasitidae), Acarologia 57 (2), pp. 211-221 : 216-221

Holoparasitus fanes n. sp.

( Figures 3-5 )

Zoobank: 5326BC8D-B3D4-450C-B686-7F7B4F836AA0

Diagnosis — In both sexes gland pores gv1 are present, and pores gv2 are located in unmodified flat cuticle. In the female, the gnathotectum is trispinate, presternal plate is ribbon-shaped, only slightly narrowed medially, with obliquely cut ends, no denticles or corrugation are present; lateral platelets free and wedge-shaped; sternal plate reticulation pronounced, axial granular or reticulated band absent, anterior sternal margin concave between st1 setae and frequently with small concavities laterally to sternal pores iv1; posterior paragynial lobes in close proximity, metagynial sclerite heavily sclerotised and located close to adaxial edge of paragynium, its antiaxial margin straight whereas the adaxial margin forms a rounded protrusion matching the concavities in the anterior subapical thickening of the epigynium; epigynial central prong much wider than the subapical structure, which is narrow and anteriorly tripartite, with lateral hyaline protrusions rounded and extending slightly beyond the central prong margins; endogynium very small in ventral perspective, with heavily sclerotised roundish structure located centrally, and the lateral parts bearing minute denticles; anteriorly, endogynium forming a lamellar protru- sion. In the male, the gnathotectum the solid central prong is rounded apically, lateral prongs absent; corniculi conical; hypostome normal; hypognathal groove clearly visible; chelicera fixed digit straight and edentate with a characteristic lamellar protrusion laterally, movable digit solid and curved adaxially, bearing one dent; pilus dentilis minute, settled in orifice in lateral protrusion of fixed digit; palpcoxal setae scarcely pectinate and hypostomatics simple; palp trochanter with stout simple seta v1 and longer seta v2 barbed terminally, both setae located in close proximity and separated by a prominence; palp femur with ventral tubercle near the anterolateral seta; sternal shield with a regular reticulation except the roundish area between coxa II and coxa III, where the reticulation is weak and the cuticle porous; genital lamina rounded, located in a concavity of the sternal margin, and flanked by the sclerotised prominences; apical segment of femur II main spur circular in the ventral perspective, axillar process wedge-like, spur on genu II moderate, the one on tibia II – low, roundish and broad; genu II extended anterolaterally in the distal part.

Description

Female — Idiosoma brownish, 475-495 x 670-675 µm (width range x length range) (n=5). Length of podonotal setae: 26-30 µm (j1), 25-26 µm (r3), others 14-17 µm; opisthonotal setae very short, 8-12 µm; length of peritrematal groove 209-215 µm.

Gnathosoma — Gnathotectum trispinate ( Fig. 3A ), corniculi conical. Hypognathal groove narrow, with ca. ten weakly pronounced rows of denticles. Palpcoxal and hypostomatic setae simple. Chelicera ( Fig. 3B ). Fixed digit with two denticles in front of pilus dentilis, one larger and lamellar, covering pilus dentilis, and two small denticles behind pilus dentilis; the latter are located somewhat below the digit edge, which is lamellar and arcuate. The movable digit bears three teeth, pedipalp trochanter with seta v1 simple, v2 longer and barbed distally; femur and genu setation unremarkable.

Ventral idiosoma — Presternal plate ( Fig. 3C ) ribbon-shaped with obliquely cut ends and only slightly narrowed medially, and with a sinuous anterior margin, no denticles or corrugation present. Lateral platelets are free and wedge-shaped. Ster- nal shield ( Fig. 3D ) anterior margin with shallow concavity between st1 setae and usually with small concavities laterally to iv1 sternal pores, reticulation well developed. Pores gv1 on sternal shield near posterior sternal margin. Setae of sternogenital region: 39 – 46 µm (st 1), 50 – 59 µm (st2), 44 – 51 µm (st 3), 33 – 39 µm (st4).

Genital region — Paragynial shields ( Fig. 3E ) reticulated, posterolateral protrusions well developed, roundish or sometimes asymmetrical. Posterior paragynial lobes in close proximity. Adaxial paragynial edge thickened and metagynial sclerite heavily sclerotised, located close to the adaxial paragynial edge; antiaxial margin of metagynial sclerite straight or slightly curved, adaxial margin forming a rounded protrusion matching concavity in the anterior subapical thickening of the epigynium ( Fig. 3E ). Thickening facing coxa III is absent. Central prong of epigynium ( Fig. 3F,G ) with convex margins, wider than the subapical structure, which is narrow and anteriorly tripartite. Lateral hyaline protrusions are rounded and extend only slightly beyond the margins of the central prong. Endogynium ( Fig. 3H,I ) is small, with heavily sclerotised roundish structure located centrally and with the lateral, less sclerotised parts bearing minute denticles; anteriorly, endogynium forms a lamellar tongue-like protrusion directed anteriorly and frequently indented apically. Gland pores gv 2 in unmodified flat cuticle. Opisthogaster with eight pairs of ventral setae 15 – 42 µm long.

Legs — Leg structure and setation unremarkable.

Male — Idiosoma brownish, 387 – 425 × 580 – 640 (n=5). Length of podonotal setae: 26 – 29 µm (j1), 16 – 18 µm (r3), others 9 – 14 µm; opisthonotal setae short, 10 – 12 µm; length of peritrematal groove 199 – 207 µm.

Gnathosoma — Gnathotectum with a solid central prong rounded apically, lateral prongs absent, gnathotectum margins convex ( Fig. 4A ). Corniculi ( Fig. 4B ) conical. Hypostome normal, hypognathal groove rather wide, and ca. 10 rows of denticles moderately visible. Palpcoxal setae scarcely pectinate, hypostomal setae simple. Chelicera ( Fig. 4 C- F). Fixed digit straight and edentate with a characteristic lateral lamellar protrusion showing a small orifice at the base of minute pilus dentilis ( Fig. 4D,F ). The protrusion is clearly visible in the ventral perspective ( Fig. 4D ). Movable digit solid and curved adaxially; bearing one tooth, in some specimens followed distally by 1-2 minute denticles. Pedipalp trochanter ( Fig. 4B,G ) with stout seta v1 and longer seta v2 barbed terminally, both setae located in close proximity and separated by a small prominence. Pedipalp femur ( Fig. 4B ) with ventral tubercle near the anterolateral seta; both femur and genu setation unremarkable.

Ventral idiosoma — Presternal platelets small and roughly triangular ( Fig. 5A ). Genital lamina ( Fig. 5B ) roundish with sclerotised margin and heavily sclerotised subgenital microsclerite. The lamina is located in the concavity of the anterior sternal margin, flanked by the sclerotised tubercles on both sides of the concavity. Reticulation of the sternogenital shield ( Fig. 5A ) clearly visible laterally, but in central part between coxa II and coxa III weakly pronounced, and the sternal cuticle is porous. Excipulum absent. Sternal setae length: 34 – 39 µm (st1), 30 – 33 µm (st2), 31 – 35 µm (st3), setae st4 27 – 30 µm, opisthogastral setae 21 – 37 µm.

Legs — Leg I, III, IV largely unremarkable, with simple setae, but anterolateral setae on trochanter I and trochanter II, which are thicker and pectinate distally ( Fig. 4H ). Leg II ( Fig. 5 C-E) spurred as follows: apical segment of femur II main spur circular in the ventral perspective, whereas the axillar process wedge-like; spur on genu II moderate, that on tibia II low, roundish and broad. genu II is extended anterolaterally in the distal part ( Fig. 5D,E ).

Etymology — The specific name refers to its type locality, Fanes in Val Travenanzes, Dolomites, Italy.

Material examined — Holotype female (slide no. 1620), 18.08.2001, Cortina d’Ampezzo, Dolomites , Italy, 46°34.329’N, 12°6.789’E, alt. ca. 1311 m a.s.l., moss on tree stump in a spruce forest near the road to Olympia Camping; 8 female and 12 male paratypes (slides no. 2000, 2001, 2002), 12.09.2005, Val Travenanzes , Dolomites, close to Fanes waterfalls ( Cascate di Fanes ), moss and litter in a spruce forest, 46°35.723’N, 12°5.185’E, alt. ca. 1455 m a.s.l.; 4 female and 4 male paratypes (slides no. 2162, 2163), 7.09. 2007, Val Travenanzes, Dolomites, litter and moss in a spruce forest, 46°35.127’N, 12°4.605’E, alt. 1635 m a.s.l.

Other material: 3 females, 4 males (slides no. 1640, 1641, 1713-1717), 10.09.2002, Cortina d’Ampezzo, Dolomites , near Olympia Camping, litter in a spruce forest, 46°34.329’N, 12°6.789’E, alt. ca. 1311 m a.s.l.; 1 male (slide no. 2011), 13.09.2005, near Olympia Camping, Cortina d’Ampezzo, Dolomites , thick layer of moss covering soil and logs in a spruce forest, 46°34.335’N, 12°6.746’E, alt. ca. 1320 m a.s.l.; 13 females, 24 males (slides no. 2179, 2180, 2182), 30.09.2008, near Dobbiaco, Dolomites, moss under trees, 46°41.520’N, 12°12.450’E, alt. ca. 1626 m a.s.l. Types are deposited in the Zoological Museum of the Jagiellonian University, Cracow, Poland, whereas the other material remains in the Author’s collection .

Holoparasitus crassisetosus species-group, newly defined. Species included:

Holoparasitus crassisetosus Juvara-Bals and Witali´nski, 2000

Holoparasitus digitiformis Juvara-Bals and Witali´nski, 2000

Diagnosis of the species group — In both sexes (1) gnathotectum trispinate; (2) gland pores gv1 present; (3) gland pores gv2 located in unmodified flat cuticle. Female — (1) gnathotectum regularly trispinate; (2) presternal plate with the anterior margin smooth, lateral platelets free, or one-sidedly accreted to presternal plate; (3) sternum entire, with regular reticulation, axial granular or reticulated band absent; (4) sternal anterior margin developed normally; (5) posterior paragynial lobes in close proximity to each other; (6) the thickening of the anterior paragynial edge facing coxa III present; (7) central epigynial prong moderate and triangular, the thickening of subapical epigynial structure well visible, compact, anteriorly rounded; (8) well sclerotised endogynium very small and roundish, with a protrusion directed dorsally. Male — (1) gnathotectum trispinate-type, but the central prong well pronounced and acute, whereas the lateral prongs minute; (2) hypostome regularly triangular and moderately sclerotised; (3) hypostomatic setae on entire cuticle, but not on the piece of cuticle separated by lateral and posterior soft-cuticular inci- sions; (4) corniculi with a circular lamellar protrusion located adaxially; (5) excipulum on the sternum absent; (6) genital lamina with a well sclerotised subgenital microsclerite and long, acute hyaline lateral protrusions; (7) pedipalp trochanter with seta v1 simple and thickened basally, seta v2 barbed terminally; (8) pedipalp femur bears a ventral tubercle; (9) femur II spur conical, with a small terminal segment, axillary process settled on the slope of femoral spur; (10) spur on genu II small and semicircular, located in the middle of the segment.

Distribution — Both species of this group are found in the central part of Italy, Tuscany, whereas H. digitiformis is also found in Sardinia (Juvara-Bals and Witali´nski 2000).

Remarks — The new species H. fanes is most similar to the H. crassisetosus species-group. It shows all the character states shared by both sexes (1-3). The females of H. fanes possess some characteristics of the group (1-5), but details of the genital orifice area are different. The males of H. fanes are similar to the H. crassisetosus group in gnathotectum and hypostome structure (1-3), sternum (5) and pedipalp (7, 8), but corniculi (4), genital lamina (6) and leg II structure (9, 10) are different.

The female of H. fanes can be distinguished from the H. crassisetosus species-group by the anteriorly tripartite, rather than rounded, thickening of the subapical epigynial structure. In the male, a porous area in the sternum center is present only in H. fanes . Moreover, the corniculi are conical and tibia II regularly spurred. These characteristics differentiate H. fanes from H. inornatus ( Berlese, 1906) and H. intermedius ( Holzmann, 1969), both species with indented corniculi. H. megacalcaratus Schmölzer, 1995 possesses conical corniculi, but with only a single, large main spur on femur II.

Figures

FIGURE 3: Holoparasitus fanes n. sp., female: A – Gnathotectum; B – Chelicera, antiaxial aspect and fixed digit in the lateroventral perspective; C – Praesternal plate with the lateral platelets; D – Sternal shield; E – Paragynial shields and apex of epigynium; F – Epigynium; G – Central epigynial prong with a subapical structure; H – Endogynium between paragynial adaxial borders; I – Endogynium. A,C,I: slide no. 1713; B: slide no. 1714, fixed digit slide no. 2002; D: slide no. 1641; E,F: slide no. 1620, holotype; G,H: slide no. 1714. Scale bars: 0.1 mm.

FIGURE 4: Holoparasitus fanes n. sp., male: A – Gnathotectum, different aspects; B – Gnathosoma, ventrally; C – Chelicera, adaxial aspect; D – Chelicerae tips in ventral perspective, arrows indicate orifices at the base of minute pilus dentilis; E – Basal part of cheliceral digits, antiaxial aspect; F – Tip of fixed digit showing pilus dentilis; G – Pedipalpal trochanter anterolaterally, seta v1 also in ventral perspective; H – Trochanter I, arrow on anterolateral side. A: slides no. 1715, 1716, 2182; B,C: slide no. 2000; D-F: slide no. 1715; G: slide no. 1716, v1 slide no. 2000; H: slide no. 2182. Scale bars: A-E,G,H – 0.1 mm, F – 0.05 mm.

FIGURE 5: Holoparasitus fanes n. sp., male: A – Sternal shield; B – Genital lamina; C – Leg II (Fe, Ge, Ti), anterolateral aspect; D – ibid., ventral aspect, arrow on anterolateral side; E – Leg II (Ge, Ti), ventral aspect, arrow on anterolateral side. A: slide no. 2001; B: slide no. 2179; C: slide no. 1640; D: slide no. 2002; E: slide no. 2000. Scale bars: 0.1 mm.