Pachylaelaps (Longipachylaelaps) marcovallei Mašán, 2017, sp. nov.
Creators: name: Mašán, Peter
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Mesostigmata
Pachylaelapidae
Pachylaelaps
Pachylaelaps marcovallei

description: Pachylaelaps (Longipachylaelaps) marcovallei sp. nov.
(Figs 27 ¯35, 38, 49, 50, 56)
Specimens examined. Holotype female: North Italy, Bergamo Province, Bergamasque Alps and Prealps, Oltre Il Colle Village, beech forest (Fagus sylvatica) with admixed spruce (Picea abies), leaf litter and soil detritus, altitude 1,100 m, 13 May 2015, coll. P. Mašán. Paratypes: 1 female and 4 males, with the same data as in holotype; 1 male, Zambla Alta Village, near to Zambla Pass, spruce forest (P. abies) with admixed beech (F. sylvatica), needle litter and soil detritus, with decomposed wood substrate, altitude 1,170 m, 13 May 2015, coll. P. Mašán.
Diagnosis. In female, tubiform structures of sperm induction system elongated, medially curved, with subdistal portions closely adjacent and directed posteriorly (Figs 29, 49, 50). Male spermatodactyl elongate, at least 2.5 times as long as movable digit, expanded and foliate proximally, moderately narrowed distally, with anterior submedial margin finely denticulated (Figs 33, 56). Palptibia with two divergent petal-like projections: antiaxial projection longer, expanded medially and rounded distally; paraxial projection shorer, subtriangular, and tapered toward obtuse apex (Figs 35, 38).
Description. FEMALE.
Dorsal idiosoma (Fig. 27). Dorsal shield 830–865 µm long and 480–505 µm wide, elongated and suboval (length/width 1.65–1.8), delicately and evenly reticulated on surface, bearing 30 pairs of dorsal setae. Dorsal setae uniform, smooth and needle-shaped, mostly subequal in length, relatively shorter and mostly with tips not reaching beyond insertions of following setae; setae z1 shortest. For length and spacing of some selected dorsal shield setae see Table 1. Dorsolateral soft integument with seven pairs of marginal setae (r6, R1, R3‒R7).
Ventral idiosoma (Fig. 28). Sternal shield 281–296 µm long, slightly shorter than genitiventral shield (length of sternal shield/length of genitiventral shield 0.92–0.99). Genitiventral shield slightly as long as wide (length 296– 306 µm, width 265–278 µm, length/width 1.07–1.12). Anal shield subtriangular, 122–134 µm long and 173–181 µm wide (length/width 0.68–0.77); anus with three circum-anal setae situated close to posterior margin of shield. Peritremes normally developed, with anterior tips reaching dorsal surface between insertions of setae z1 and z2. Ventral shields with delicate reticulation on surface. Metapodal platelets minuscule, free on soft integument.
Ventral soft integument with nine pairs of ventral setae (JV2–JV5, ZV1–ZV5). Ventral setae similar to those on dorsal idiosoma.
Sperm induction structures (Figs 29, 49, 50). Tubiform structures of sperm induction system contiguous to anterior inner margin of coxae IV, well developed and sclerotised (especially in their distal portions), relatively large, moderately elongated, widened basally, curved medially, regularly rounded apically, and with adjacent subdistal portions directed posteriorly.
Gnathosomal structures (Figs 30, 31). Corniculi elongated and horn-like; laciniae densely pilose, as long as corniculi; deutosternum with six rows of denticles; subcapitular setae smooth and needle-shaped. Epistome with subtriangular and regularly narrowed base, narrow central neck and widened apical part densely crenulate anteriorly; basal part with irregularly denticulate lateral margins (Fig. 30). Fixed digit of chelicera with bifid terminal hook, one large distal tooth associated with pilus dentilis, and one additional distal denticle on lateral ridge; pilus dentilis well developed, curved and directed backward; movable digit of chelicera unidentate, with simple hook and one distal tooth (Fig. 31).
Legs. Leg setation normal for genus (Mašán, 2007). Tarsus II with two spur-like distal setae, pl1 and pl2 (Fig. 32).
MALE. Dorsal idiosoma. Dorsal shield 710‒750 µm long and 430‒500 µm wide, elongated and suboval (length/width 1.5‒1.7).
Ventral idiosoma. Sternal, genitiventral, peritrematal, metapodal and anal plates fused to form an entire holoventral shield bearing nine pairs of setae (st1‒st5, JV1‒JV3, ZV2), not including three circum-anal setae close to anus; shield with reticulate sculpture on surface. Dorsolateral and ventral soft integument with 13 pairs of setae (r6, R1, R3‒R7, JV4, JV5, Zv1, ZV3‒ZV5). Dorsal and ventral chaetotaxy and other characters as in female.
Gnathosomal structures (Figs 33, 35, 38, 56). Cheliceral spermatodactyl well developed, elongate, 16 5‒185 µm long, 2.5‒2.85 times as long as movable digit, foliately expanded proximally, moderately narrowed in distalmost portion, with anterior submedial margin finely denticulated (Figs 33, 56). Palptibiae slightly thickened basally, each bearing a pair of petal-like projections on proximal ventral surface, as in Figs 35 and 38; projections relatively large, with divergent adjacent margins: antiaxial projection longer, with narrow base, medial expansion and rounded distal margin, lacking small lamellar structure in its inner basal margin; paraxial projection shorer, subtriangular, widened basally and tapered toward obtuse apex. Palpfemur with distinct papular tubercle on anterolateral basal surface.
Legs. Medial segments of legs II spurred on their distal ventral surface: femur with one robust spur, genu and tibia each with a peg-like spur, as in Fig. 34. Femoral spur broadened in basal part, produced into narrowly rounded apex, with two small tubercles on axillary side (Fig. 34). Terminal part of tarsus II with only one spur-like distal seta, pl1.
Etymology. This species is named in honour of Marco Valle, eminent and esteemed zoologist and museologist, director of the Natural History Museum in Bergamo (Museo Civico di Scienze Naturali "Enrico Caffi"), who did many years of patient work especially on the diversity and biology of the Italian caddisflies (Trichoptera).
Taxonomic notes. The main diagnostic character states for Pachylaelaps (Longipachylaelaps) marcovallei are the presence of "pendulous" sperm tubes in females and the denticulation of the anterior submedial margin of the spermatodactyl in males. This denticulation has not been reported before in the family Pachylaelapidae. The characters that separate the new species from its congeners are detailed in Table 2.
description: Published as part of Mašán, Peter, 2017, Four new species of the subgenus Pachylaelaps (Longipachylaelaps) from Italy, with a new identification key to the known species (Acari: Pachylaelapidae), pp. 95-117 in Zootaxa 4236 (1) on pages 103-106, DOI: 10.11646/zootaxa.4236.1.5, http://zenodo.org/record/322026