Arabapolonia, Stekolnikov, Alexandr A., Carranza, Salvador & Gomez-Diaz, Elena, 2012

Stekolnikov, Alexandr A., Carranza, Salvador & Gomez-Diaz, Elena, 2012, A new genus and species of Apoloniinae (Acari: Trombiculidae) from Oman, Zootaxa 3499, pp. 74-80 : 75-76

Arabapolonia gen. nov.

Type species: Arabapolonia omanensis sp. nov., designated here.

Diagnosis. SIF = 6BS-N(b)-1-2110.0000; fsp = 7.7.7; fCx = 1.0.1; fSt = 0.2.4; fPp = B/B/BBB. Cheliceral blade with 1 inconspicuous denticle near its apex; galeal seta nude or having 1 small cilium; palpal claw single; all palpal setae branched; palpal tarsus with 6 non-specialized setae, nude subterminala and tarsala. Tracheae present; spiracles not found. Scutum with projected anterior margin, without nasus, posterior scutal margin slightly prominent, angulated or rounded; two anteromedian setae, two anterolateral and two posterolateral setae situated on scutum; sensilla flagelliform, branched in distal half; eyes 2 + 2. Legs 7-segmented, with 1 pair of claws and claw-like empodium; onychotriches present; leg subterminala and parasubterminala absent; pretarsalae I (?) and II absent; microgenuala II absent; microtarsala I situated distal of tarsala I; microtarsala II situated distal of tarsala II; tarsala II slender, with bulbiform apex; tibiala III and mastitarsalae III absent. Number of setae on leg coxae I–III: 1, 0, 1; sternal setae between coxae I absent; two sternal setae between coxae II and four sternal setae between coxae III.

Hosts. Geckos of the families Gekkonidae , Phyllodactylidae and Sphaerodactylidae .

Distribution. Oman.

Etymology. The name of the new genus refers to the Arabian Peninsula, where its type species was found, and to Apolonia Torres and Braga, 1939 , the nominate genus of Apoloniinae.

Remarks. Arabapolonia differs from all other Apoloniinae in a single palpal claw, the absence of coxala II (fCx = 1.0.1 vs. 1.1.1 or 1.2.1) and the absence of the sternal setae between leg coxae I (fSt = 0.2.4). The new genus shares the non-reduced scutum with the genera Sauracarella Lawrence, 1949 and Afracarella Vercammen- Grandjean and Kolebinova, 1968 (all other genera of Apoloniinae have peniscutum, i.e. scutum with reduced posterior angles, with PL setae situated off scutum), but these two genera, unlike Arabapolonia , possess the nasus and clavate sensilla. Arabapolonia is the second known genus of Apoloniinae (after the monotypic genus Apolonia ) having onychotriches and the second genus with palpal tarsus 6BS (after the monotypic genus Afracarella ).

Arabapolonia is the first known Apoloniinae genus having tracheae. These structures belong to the duct system of unknown function which was previously recorded in some genera of Leeuwenhoekiinae ( Goff et al. 1982), while in other genera of this subfamily it is certainly absent.

We were unable to find pretarsala on leg I in the new genus; actually, in the compact group of setae at the tip of the tarsus, one seta may be pretarsala, but its recognition can probably be realized only on new material of better quality or by scanning electron microscope. Tentatively, the absence of this seta can be regarded as another autapomorphy of Arabapolonia .