Scarabacariphis, Masan, 1994

Kazemi, S., 2016, Redefinition of the genus Scarabacariphis MašAEn and new morphological data for S. geotrupes comb. nov. (Ishikawa) (Acari: Mesostigmata: Eviphididae), Acarologia 56 (1), pp. 129-135 : 130

Genus Scarabacariphis MašAEn, 1994

Scarabacariphis MašAEn, 1994: 6.

Type species Scarabacariphis grandisternalis MašAEn, 1994 (= Alliphis ankavani Arutunian, 1992 ), by original designation.

Diagnosis — Idiosoma completely or partly covered by dorsal shield. Dorsal shield almost flattened, sub-oval, entire, finely reticulated over entire surface, free from peritrematal shields, usually bearing 29-30 pairs of mostly needle-like and short setae, with 22 pairs of pore-like structures, including six pairs of gland pores (gd1-2, gd4, gd6, gd8-9). Weakly sclerotized presternal platelets present or absent. Sternal shield entire, almost as long as wide, with three pairs of simple narrow setae and two pairs of poroids, iv1 slit-like, oriented obliquely, iv2 ovoid. Endopodal platelets between coxae II-III completely fused to sternal shield; endopodals between coxae III-IV not enlarged, free. Metasternal setae and poroids iv3 on soft integument or situated on minute metasternal platelets. Epigynal shield inconspicuously reticulated, anterior hyaline margin of shield rounded, setae st5 on lateral marginal of shield or in soft integument; postgenital platelets absent. Anal shield subtriangular or pear-shaped, bearing simple and slender subequal circumanal setae. Exopodal platelets between coxae III-IV always present, those between coxae I-III present or absent; parapodal platelets narrow, free. Metapodal platelets small, narrow. Peritrematal shields finely developed along peritremes, free, post stigmatic section tapered, not extending beyond posterior level of coxae IV, with three pairs of poroids and two pairs of gland pores. Peritremes extending to anterior level of coxae I to II. Dorsolateral and ventral integument simply striated, in female with 10 pairs of simple setae (excluding st5), in male with eight setae. Sternogenital shield of male well separated from anal shield. Deutosternal groove with five rows of denticles, each with 2-13 teeth. Movable digit of female chelicera with one large tooth. Palpgenu with six setae. Palptarsus with one sicklelike seta and two-tined apotele. Epistome with long median projection, and wing-like lateral elements. Complement of leg chaetotaxy as: coxae 2-2-2-1; trochanter 6-5-5-5; femora 13-11-6-6; genua 11-11- 8-7; tibiae 11-10-7-7. Male legs without spurs.

Notes on the genus — Ishikawa (1979) described an eviphidid species with most typical characters of the genus Alliphis , A. geotrupes , but he illustrated its peritrematal shields free from the dorsal shield. I confirmed this observation in the paratype specimen. The only genera of Eviphididae that bear free peritrematal shields from the dorsal shield are Rafaphis Skorupski & Błaszak, 1997 and Scarabacariphis , so the placement of A. geotrupes is not acceptable. Comparing these genera with free peritrematal shields, Raphafis is unrelated to A. geotrupes because of its unique character states for the Eviphididae , such as the dorsal shield extending ventrally and capturing three pairs of opisthogastric setae, reduced and sub-oval sternal shield, atypical leg chaetotaxy and also epistome. Although Scarabacariphis shares several characters with A. geotrupes , there are some morphological differences between the type species of this monotypic genus and A. geotrupes , including the absence of larval setae J 2 in the latter species (present in S. ankavani ), setae st5 off the epigynal shield (on the shield in S. ankavani ), and exopodal platelets between coxae I- III present and small (absent in S. ankavani ). Currently, the only eviphidid genus without setae J2 is Podoniphis Joharchi et al., 2014, but they can be easily separated by the rudimentary peritrematal shields fused to the dorsal shield in Podoniphis, most dorsal shield setae in Podoniphis relatively elongated, except J5 minute and strongly reduced (setae J 5 in Scarabacariphis and Alliphis not reduced, other setae not elongated) and also presence of a robust spine-like ventral setae in femur II of the female (absent in females of Scarabacariphis and Alliphis ). The insertion of setae st5 off the epigynal shield can be seen in Scarabaspis Womersley, 1956 and some species of Thinoseius Halbert, 1920 , and also with intraspecific variation in Podoniphis persicus Joharchi et al., 2014 (on or off the shield but near its bor- der). Moreover, although all of these mites have peritrematal shields fused to the dorsal shield, the members of Scarabaspis bear two sickle-like sensory setae on palptarsus (in contrast one in Scarabacariphis and Alliphis ) and also flattened oval-shaped disc setae on coxae I-II (simple setae in Scarabacariphis and Alliphis ); Thinoseius has some meaningful different characters that mostly seem to be autapomorphic attributes within Eviphididae , including presence of five setae on the palpgenu (six setae in other eviphidids), female dorsal shield with 11-17 pairs of setae showing considerable sexual dimorphism and also female sternal shield absent, reduced or fragmented into sclerotized platelets. So, based on these observations I propose to transfer Alliphis geotrupes to Scarabacariphis (see more in discussion).