Eryngiopus Summers

Rehman, Muneeb Ur, Kamran, Muhammad & Alatawi, Fahad J., 2018, Genus Eryngiopus Summers (Acari: Trombidiformes: Stigmaeidae) from Saudi Arabia; a new record and redescription of E. discus Meyer, with a key to the world species, Acarologia 58 (3), pp. 655-664 : 656

Genus: Eryngiopus Summers

Eryngiopus Summers, 1964: 186 .

Type species: Eryngiopus gracilis Summers, 1964 .

Diagnosis based on Fan & Zhang (2005).

In the present study, the species of genus Eryngiopus are categorized into two species groups based on the number of prodorsal setae ( Table 1); 1) species group bakeri having three pairs of prodorsal setae (vi, ve and sci) including nine species reported from Turkey, Egypt,

Yemen, Thailand, China, South Africa and USA; 2) species group gracilis having four pairs of prodorsal setae (vi, ve, sci and sce) comprising 22 species mostly reported from USA, New

Zealand, Italy, South Africa, China, Russia, Uzbekistan, Iran, Pakistan and India ( Doğan et al.,

2015, Fan et al., 2016).

Number of prodorsal setae, either 3 pairs (vi, ve, sci) or four pairs (vi, ve, sci, sce) ( Table 1),

is strong and constant morphological character to categorize the species Eryngiopus of into two species groups. Vacante & Gerson (1988) used number of prodorsal setae (three/four) pairs as an important and basic character to develop a key to 17 world species of Eryngiopus . Also, Van

Dis & Ueckermann (1993) separated the Afrotropical Eryngiopus species and used number of prodorsal setae (three/four) pairs as the first couplet in the key.