Pneumolaelaps (Hypoaspisella), Joharchi & Halliday & Khaustov & Ermilov, 2018, Joharchi & Halliday & Khaustov & Ermilov, 2018

Joharchi, Omid, Halliday, Bruce, Khaustov, Alexander A. & Ermilov, Sergey G., 2018, Some soil-inhabiting mites from Zanzibar (Acari: Laelapidae), Zootaxa 4514 (1), pp. 23-40 : 26-28

Genus Hypoaspisella Bernhard stat. nov.

Hypoaspis (Hypoaspisella) Bernhard, in Karg, 1962: 64 . Type species Hypoaspis (Hypoaspisella) heyi Karg, 1962 , by monotypy.

Hypoaspis (Hypoaspisella) Bernhard, 1971: 6 . Type species Hypoaspisella berlesei Bernhard, in Hirschmann et al., 1969 , by original designation.

Diagnosis. Dorsal shield sub-oval, almost completely covering dorsal idiosoma, dorsal shield bearing at least one Zx setae, unpaired setae Jx sometimes present; dorsolateral soft integument with 0–9 pairs of simple setae, presternal platelets always present, metasternal setae (st4) always present and situated on soft cuticle; genital shield tongue-or-flask-shaped, bearing one pair of simple setae and well separated from anal shield; anal shield subtriangular or pear-shaped; peritremes long extending to coxa I, peritrematal shield never enlarged around stigmatic opening; opisthogastric soft cuticle bearing 7–12 pairs of smooth pointed setae; anterior margin of epistome always smooth; deutosternal groove with six rows of denticles, each row bearing two to seven denticles; lateral branches of the internal malae absent, chelicerae well developed, chelate-dentate, pilus dentilis setiform; all legs with ambulacra and claws, leg chaetotaxy normal for Laelapidae , genu IV usually with nine setae 2 2/1 3/0 1.

Hypoaspisella is similar to Gaeolaelaps and Pneumolaelaps Berlese, 1920 , but can be easily distinguished from both of these genera. The most significant character that separates Hypoaspisella from the other two genera is the shape of the anterior margin of the epistome, which is curved and smooth in Hypoaspisella but denticulate and gable-shaped in Gaeolaelaps and Pneumolaelaps respectively. The deutosternal groove is reduced in Hypoaspisella , with 2–7 denticles per row, and no large teeth (versus with 1–5 denticles per row and at least one denticle per row enlarged in Pneumolaelaps ). Also, the lateral branches of the internal malae are absent in most species of Hypoaspisella . In most species of Hypoaspisella there is only one ventral seta on genu IV, and all species occur in soil. In Pneumolaelaps genu IV always bears two ventral setae and its species are always associated with bumblebees. The peritrematal shields are widened in Pneumolaelaps and narrow in Hypoaspisella (see table 1).

Notes on the genus. The nomenclatural history of Hypoaspisella presents some unusual problems. The name Hypoaspisella was first used as a subgenus of Hypoaspis by Bernhard (1955) in an unpublished PhD thesis (not seen by us). No new names are available from that source, because the thesis does not satisfy Article 8.1.3 of the International Code of Zoological Nomenclature. Karg (1962) described Hypoaspis (Hypoaspisella) heyi as a new species, placed in the subgenus Hypoaspis (Hypoaspisella) Bernhard, 1955 . In his discussion of H. heyi, Karg provided enough descriptive information to make the name Hypoaspisella available. He also mentioned the name H. intermedius Bernhard, 1955 as a member of the subgenus, but H. intermedius is a nomen nudum. Hypoaspis heyi is therefore the only nominal species included in Hypoaspis (Hypoaspisella) , and becomes its type species by monotypy. Karg (1965) included Hypoaspisella in a key to genera and subgenera of Hypoaspidinae, and repeated his assertion that its type species is H. heyi . He also added Hypoaspis (Hypoaspisella) richteri Karg, 1965 and H. (H.) procera Karg, 1965 to the subgenus. Hirschmann et al. (1969) then described and illustrated five species of Hypoaspis (Hypoaspisella) , four of which were shown with authorship "Bernhard 1955 i. l.". The notation "i.l." is an abbreviation of in litteris, meaning unpublished, and correctly refers to Bernhard's 1955 thesis. Bernhard (1971, page 6) provided a more complete description of " Hypoaspisella nov. subgen. " and stated that its type species is " Hypoaspisella berlesei nov. spec. ". This action overlooks that fact that Karg had designated H. heyi as the type species, and that H. berlesei had been made available by Hirschmann et al. (1969).

Karg (1971) treated Hypoaspisella as a junior synonym of a very broadly conceived subgenus Hypoaspis (Holostaspis) Kolenati, 1858 , which also included Pneumolaelaps . Karg (1979, 1982, 1993), however, placed Hypoaspis (Hypoaspisella) heyi in Hypoaspis (Pneumolaelaps) , which makes Hypoaspisella a synonym of Pneumolaelaps . Karg (1993) also considered H. richteri as a synonym of Hypoaspis (Holostaspis) forcipata (Willmann) .

Karg (1971) described Hypoaspis (Holostaspis) lubricoides as a new species. Khalili-Moghadam et al (2016) recorded this species from Iran, and reclassified it as Pneumolaelaps (Hypoaspisella) lubricoides (Karg) , without providing an explanation. That record was catalogued by Nemati et al. (2018). However H. lubricoides is certainly not consistent with current concepts of Pneumolaelaps , because in Pneumolaelaps genu IV always bears two ventral setae, and all the known species are associated with bumblebees. In addition, the peritrematal shields are widened in Pneumolaelaps but narrow in H. lubricoides . This species is consistent with the concept of Hypoaspisella we have used here, but the description of H. lubricoides is brief and both the description and illustrations lack many important details. It will be necessary to examine the type specimens before its correct placement can be determined.

We consider Hypoaspisella as a valid genus, which differs from Pneumolaelaps in a number of characters as discussed in the diagnosis above. It appears likely that some of the 27 species placed in Hypoaspis (Pneumolaelaps) by Karg (1993) will be transferred to Hypoaspisella or some other genus, after a detailed revision of these species. The current composition of the genus Hypoaspisella becomes:

Hypoaspisella berlesei (Bernhard, in Hirschmann et al., 1969)

Hypoaspisella heterosetosus (Bernhard, in Hirschmann et al., 1969)

Hypoaspisella heyi ( Karg, 1962)

Hypoaspisella intermedius (Bernhard, in Hirschmann et al., 1969)

Hypoaspisella lasiomyrmecophilus ( Hirschmann et al., 1969)

Hypoaspisella procera ( Karg, 1965) (= Hypoaspis incertus Bernhard, in Hirschmann et al., 1969 ).