Geholaspis Berlese, 1918

Emberson, Rowan M., 2010, A reappraisal of some basal lineages of the family Macrochelidae, with the description of a new genus (Acarina: Mesostigmata), Zootaxa 2501, pp. 37-53 : 40-41

Geholaspis Berlese, 1918

Geholaspini with normally developed, robust chelicerae, fixed chelae with fewer than six teeth ( Fig. 4 ); epistome triangular basally, with elongate median process ( Fig. 5 ), or narrow, bifid median process; ventrianal shield with five pairs of pre-anal setae.

The dorsal shield has 28 pairs of setae, which may be either aciculate, lightly plumose, or distinctly plumose. A group of aciculate setae is present in the centre of the shield including at least j5, j6, z5, z6, and J2. Setae j1 are relatively short and plumose, while setae z1 are long and usually aciculate, but may be lightly plumose ( G. pauperior Berlese , G. ponticus Bregetova & Koroleva ). Setae j5 are displaced posteriorly so that they lie behind setae z5; they may be either anterior or just posterior to setae j6. The ventral sclerotisation is well developed; the metasternal platelets may either be free with the usual seta and pore (subgenus Geholaspis s. str.), or fused to the endopodal shields (subgenus Cyrtocheles ). The epigynal shield is well sclerotised, ornamented with a punctate lineal pattern and has a truncate posterior margin. The ventri-anal shield is usually broader than long, and bears five pairs of pre-anal setae and the inguinal pores. The chelicerae are robust, with fewer than six teeth on the fixed chela ( Fig. 4 ). The epistome is basically triangular and may have an elongate, tapering median process with distinct shoulders (i.e. G. longispinosus (Kramer) ( Fig. 5 )), or dentate lateral margins and a narrow, distally bifid median process. Spermathecal structures are usually not apparent, but the elongate tubuli and rami of one species have been illustrated by Athias-Henriot (1968). Males, where known ( G. alpinus (Berlese) , G. biperforatus Krauss , G. ponticus ), have holoventral shields, a short, dorsally directed spermatodactyl and a small spur on femur II.

Notes. Geholaspis is a mainly Western Palaearctic genus, known from Ireland to the Caucasus ( Bregetova & Koroleva, 1960; Hyatt & Emberson, 1988), but it is apparently most diverse in Central and Southern Europe ( Krauss, 1970; Mašán, 2003). The genus is also recorded from North America, and G. longispinosus has established in New Zealand, evidently through human agency ( Emberson, 1973).

Included species: Subgenus Geholaspis s. str.: G. aeneus Krauss, 1970 ; G. alpinus ( Berlese, 1887) ; G. berlesei Valle, 1953 ; G. biperforatus Krauss, 1970 ; G. comelicensis Lombardini, 1962 ; G. forolivensis Lombardini, 1943 ; G. longispinosus ( Kramer, 1876) ; G. pauperior Berlese, 1918 ; G. terrestris ( Berlese, 1889) . Subgenus Cyrtocheles Valle, 1953 : G. asper ( Berlese, 1904) ; G. ponticus Bregetova & Koroleva, 1960 .

Figures

FIGURES 1 – 7. 1 – 3, Dissoloncha superbus (Hull), female. 1. Epistome; 2. Ventri-anal shield; 3. Sacculus complex. 4 – 5. Geholaspis longispinosus (Kramer), female. 4. Chelicera; 5. Epistome. 6. Longicheles hortorum (Berlese) comb. nov., female, chelicera with accessory teeth on external face. 7. Longicheles mandibularis (Berlese), female, epistome.