Holoparasitus lawrencei, Hyatt, 1987

Ilinca Juvara-Bals, 2017, New and rare species of Holoparasitus Oudemans, 1936 (Acari, Gamasida, Parasitidae) from the Athias-Henriot Collection, Revue suisse de Zoologie 124 (2), pp. 225-239 : 232

lawrencei species group

Remarks: Holoparasitus lawrencei and H. paralawrencei sp. nov. cannot be included in any of the previously known species-groups which lack an excipulum. Therefore these two species are placed in a new species group which is close to caesus -group and has a similar pattern of reticulation on the ventral idiosoma in male and female. Other similarities between both groups are the characteristics of the fixed digit of the male chelicera which has only 1 or 2 denticles in H. tuberculatus Juvara-Bals, 1975 and is indented in H. fortunatus Juvara-Bals, 1975 . Both species groups differ in the armature of leg II, in features of palpfemur and palpgenual, and in characters of the epi- and endogynium in females. Only the particular characters of this group are mentioned.

Diagnosis: Both sexes: Gnathotectum trispinate, with central prong long and lateral prongs tiny; on ventral idiosoma gland pore gv1 simple and gv2 double on an unmodified cuticle.

Male: Gnathosoma without lateral incisions under setae hyp.2; corniculi conical; chelicera with fixed digit edentate and mobile digit without or with 1 or 2 denticles. Genital lamina without subgenital microsclerites. Ventral idiosoma reticulated, with one conspicuous line delimiting a slightly raised central part between st1 and st2 and a second less noticeable line between st3 and st4. Armature of leg II: rounded femoral apophysis and trapezoidal process with their apices at the same level; ellipsoidal genual apophysis near anterior margin of the segment; large triangular or rounded (40 long) tibial apophysis.

Female: Presternal plate slightly denticulate, lateral platelets free; sternal shield reticulated, with a pair of lines starting between coxa II and III and running towards the middle of the shield where they join ( H. paralawrencei sp. nov.) or not ( H. lawrencei ). Apex of epigynium mucronate, subapical epigynial structure trapezoidal, with small membranous wings. Endogynium a big sack with ventrally two spherical protuberances continued dorsally by two elongated and denticulate structures. Endogynium covered with a fine membrane.

Distribution and remarks: Holoparasitus lawrencei was recorded from Great Britain and Ireland ( Hyatt, 1987). Holoparasitus paralawrencei sp. nov. was sampled by Prof. H. Franz in the north-west of Spain. In the Athias-Henriot Collection I identified other specimens from the north of Spain: Prov. Ourense (Sp. 408), Prov. Pontevedra (Sp. 483), and the Principado de Asturia (Sp. 498). The characteristics of the Spanish specimens are closed to those of H. lawrencei and H. paralawrencei sp. nov. Unfortunately not enough material is available to identify them properly.

Species included: Holoparasitus lawrencei Hyatt, 1987 and H. paralawrencei sp. nov.