Heteroparasitus mariae, Witaliński, Wojciech, 2008

Witaliński, Wojciech, 2008, A new species of Heteroparasitus Juvara-Bals 1975 from Karavanke, Austria (Acari: Parasitidae), Zootaxa 1750, pp. 53-58 : 53-57

Heteroparasitus mariae sp. nov.

( Figs 1–19 )

Material examined. Holotype. Female (slide no. 2140), 23 July 2007, close to St. Leonhard Church, Karavanke mountains, Austria, 46o 26' 45.3" N, 14° 38' 59.4" E, alt. ca. 1410 m a.s.l., wet moss ( Sphagnum ) around water outflow. Paratypes. 7 females, 3 males (slides no. 2141-2146), same data as holotype. The types have been deposited in the Zoological Museum of the Jagiellonian University, Cracow, Poland.

Diagnosis. Gnathotectum of both sexes trispinate; trochanters III and IV with tubercles.

Female: Sternum with thickened anterior margin; paragynia interdigitate along zigzag axial margins; epigynial subapical structure rectangular in outline, with lamellar lateral protrusions extending far from margin of epigynium; endogynium cup-shaped and elliptical in ventral perspective, with several minute denticles at its entrance; movable digit of chelicera with 3 or 4 teeth; trochanter IV with posteroventral spur-like protrusion.

Male: Corniculi slender, without protrusion on adaxial surface; fixed digit of chelicera edentate, movable digit with several small uniform teeth followed by a larger proximal tooth; femur of leg II with conical and somewhat anterolaterally curved spur; spur on genu roundish and close to distal margin of segment; spur on tibia wedge-like and distally pointed.

Description. Female

Idiosoma brownish, 465–505 x 690–735 µm, length/width 1.39–1.57 (n=6). Length of podonotal and opisthonotal setae: 48–52 μm (j 1), remaining setae 33–44 μm; length of peritrematal groove 216–225 μm.

Ve n t e r. Lateral presternal platelets small and triangular. Sternum ( Fig. 1 ) regularly reticulated, its anterior margin more pigmented and thickened due to incorporation of a presternal plate. Antero-lateral reticulation forming a row of cells distinctly inclined toward the opening of coxae II; line of reticulation running through the second pair of pores (iv 2) more pronounced and indented anteriorly. Gland pores gv 1- gv 3 present. Setae of sternogenital region: 42–47 µm (st 1), 42–44 µm (st 2), 41–42 µm (st 3, st 4).

Genital region. Paragynial shields ( Fig. 2 ) showing zigzag connection along midline and relatively small posterior paragynial lobes. Central prong of epigynial shield ( Fig. 3 ) triangular. Subapical structure rectangular in outline, lateral protrusions moderately sclerotised, ending far beyond margin of epigynium. Endogynium ( Figs 4, 5 ) cup-like; in ventral perspective its entrance is oval and extended laterally, showing several minute denticles. Endogynial lamella absent. Gland pores gv 2 in unmodified cuticle. Opisthogaster normally with seven pairs of ventral setae, 33–35 µm (V 1), 34–43 µm (others). In three of six females the number of opisthogastric setae varied due to the absence of ZV 1 on one side or the presence of an additional seta between ZV 2 and ZV 3). Numbers of left/right setae were 7/6 (ZV 1 lacking), 7/8 (additional seta present) and 7/8 (on both sides additional setae present, on left side ZV 1 lacking).

Gnathosoma . Gnathotectum ( Fig. 8 ) trispinate with long acute central prong, lateral prongs much smaller, corniculi conical ( Fig. 9 ). Hypognathal groove ( Fig. 9 ) with 11–13 rows of denticles; anterior rows well pronounced, posterior rows barely visible in some specimens. Palpcoxal setae barbed, hypostomatic setae simple. Fixed digit of chelicera with two teeth in front and two behind the pilus dentilis, followed by lamellar edge ( Figs 6, 7 ); movable digit with three or four teeth ( Fig. 7 ). Palp trochanter with seta v 1 simple and v 2 finely barbed.

Legs. Leg structure and setation normal for genus, except trochanter III with a posteroventral tubercle and trochanter IV with an anterodorsal tubercle and posteroventral spur-like protrusion; coxa IV with anterolateral tubercle ( Figs 10, 11 ).

Male

Idiosoma brownish, 385 x 625–645 µm, length/width 1.61–1.66 (n=2). Length of podonotal setae: 42–55 μm (j 1), 25–33 μm (j 2), remaining setae 27–44 μm; opisthonotal setae slightly shorter, 24–39 μm; length of peritrematal groove 190–200 μm.

Ve n t e r. Presternal plates moderately sclerotised ( Fig. 12 ). Genital lamina ( Figs 12, 13 ) with a hyaline anterior edge and apically rounded lateral wing-like projections, sclerotisation of lamina paired and distinct; subgenital sclerite ribbon-shaped. Anterior sternal margin normally sclerotised, slightly more so along the concavity containing the genital lamina, this concavity flanked by tubercular protrusions ( Fig. 12 ). Sternal reticulation inconspicuous, lines running through pores iv 2 more pronounced. Gland pores gv 1 lie between setae st3. Two pairs of small thickenings located between pores iv 3. Gland pores gv 2 in unmodified cuticle. Approximate length of sternal setae: 42 µm (st 1), 33 µm (st 2), 31 µm (st 3, st 4); length of opisthogastric setae 34–39 µm.

Gnathosoma . Gnathotectum trispinate as in female. Hypognathal groove ( Fig. 14 ) with 11 or 12 rows of denticles; palpcoxal setae finely barbed, hypostomatic setae simple, located on area of cuticle isolated by deep incisions; hypostomatic setae 1 on tubercles. Corniculi conical and slim, without any adaxial protrusions. Chelicera with fixed digit straight and relatively narrow, edentate ( Fig. 15 ). Movable digit with five minute denticles followed proximally by larger tooth. Arthrodial membrane with a prominent brush-like process, synarthrodial membrane acute, ending closely behind the proximal tooth of the movable digit. Palp trochanter ( Fig. 16 ) with ventral tubercle placed proximally, ventral setae next to each other: seta v 1 simple and located on tubercle, seta v 2 barbed. Palp femur with small tubercle located ventrally at the level of anterolateral seta.

Legs. Leg II spurred as follows ( Fig. 19 ): main spur on femur conical and slightly curved, axillary process setiform. Spur on genu roundish, spur on tibia wedge-like and pointed distally, ending close to distal margin of segment. On tibia II, anterolateral seta al 1 not on elevation and posteroventral seta pv 1 larger than that on genu II. Trochanters III and IV with posteroventral tubercles ( Figs. 17, 18 ). Other segments of legs as for female.

Etymology. This species is named in honour of Maria Florek, who collected and kindly provided the type material.

Discussion. Heteroparasitus is a relatively rare European genus of local distribution, inhabiting wet litter or moss in relatively undisturbed deciduous or mixed forests, frequently on limestone terrain.

The revision of Heteroparasitus by Juvara-Bals (2002) lists characters of Heteroparasitus s. str. based on the three species that were known at that time. The description of H. mariae sp. nov. permits a review of the genus and subgenus diagnoses. At the generic level, the number of teeth on the movable digit of the chelicera in females, and the number of opisthogastric setae, are variable. In H. tirolensis and H. coronarius , the movable digit has four teeth, whereas in H. quadratus the number of teeth varies - three or more frequently four teeth occur. In H. mariae , the number of teeth can also vary even on both chelicerae of the same specimen. This diagnostic character must therefore be considered as variable.

The typical number of opisthogastric setae in Heteroparasitus is seven pairs. This character is stable in H. tirolensis but variable in H. mariae and H. quadratus . H. coronarius has not been studied in this respect. In H.

quadratus , females showing a complete set of eight pairs of opisthogastric setae can also be found (Witaliński unpublished).

The diagnostic definition of the male corniculi should also be modified. The corniculi of males may possess adaxial protrusions as in H. tirolensis and H. coronarius , or the corniculi are conical with either indiscernible or weakly visible protrusions, as in H. quadratus . The corniculi of H. mariae males are even more slender and devoid of any extensions or protuberances on their adaxial sides. Consequently, the corniculi in the subgenus Heteroparasitus can be defined as either conical or with adaxial protrusions.

Other taxonomic characters for Heteroparasitus at the generic and subgeneric levels remain as defined by Juvara-Bals (2002). Chaetotaxy, poroidotaxy and adenotaxy in H. mariae are in accord with those given for the Heteroparasitus subgenus.

Figures

FIGURES 1 – 11. Heteroparasitus (H.) mariae sp. nov., female: 1, sternal shield; 2, paragynia; 3, epigynium; 4, endogynium, ventral perspective (intact specimen); 5, endogynium, posterior perspective (squashed specimen); 6, chelicera, adaxial view; 7, movable digit of chelicera; 8, gnathotectum; 9, gnathosoma, ventral view; 10, trochanter III, ventral; 11, coxa IV and trochanter IV, ventral. (1, 2, 9 – 11, slide number 2140 (holotype); 3, 4, 7: slide number 2141 (paratype); 5, 6, 8: slide number 2142 (paratype )). Scale bars 0.1 mm.

FIGURES 12 – 20. Heteroparasitus (H.) mariae sp. nov., male: 12, sternal shield and genital lamina; 13, genital lamina; 14, corniculus and hypognathal groove; 15, chelicera, antiaxial; 16, palp trochanter, lateral; 17, trochanter III, ventral; 18, trochanter IV, ventral; 19, leg II, femur, genu and tibia, anterolateral. Heteroparasitus (H.) quadratus (Witaliński), male: 20, leg II, genu and tibia, posteroventral. (12, 13, 15 – 19: slide no. 2145 (paratype); 14: slide number 2143 (paratype); 20: slide number 2067). Scale bars 0.1 mm.