Cicaditrombium, Saboori, Alireza & Lazarboni, Hossein, 2008

Saboori, Alireza & Lazarboni, Hossein, 2008, A new genus and species of Trombidiidae (Acari: Trombidioidea) described from larvae ectoparasitic on Cicadatra ochreata Melichar (Homoptera: Cicadidae) from Iran, Zootaxa 1852, pp. 50-58 : 51-52

Genus Cicaditrombium gen. nov.

Type-species: Cicaditrombium weni sp. nov. (monotypic)

Diagnosis of larva: Idiosoma with two median dorsal scuta; lateral setae on coxa I with one setula; coxa II with two setulose setae, seta 2a situated in antero-median border and 2b in postero-lateral part of coxa. Ge II and III each with one solenidion; Ge I and Fe II with four normal setae each; Ta III with short and thick inner claw; gnathosoma rounded posteriorly; palp - tibial claw distinctly bifurcate; subcapitular setae long and with setules on proximal half and smooth on distal half; adoral seta on projection; famulus absent on Ta I, present on Ta II; supracoxal setae present on gnathosoma.

Etymology: The generic name is derived from the root name of its host family “Cicadidae-” and “trombium” (Greek, = the root name of Trombidiidae ). Neutral in gender.

Remarks: Welbourn (1991) divided Trombidiidae into the subfamilies Podothrombiinae, Trombidiinae and Allothrombiinae. Makol (2007), who confirmed a separate family affiliation of Podothrombiinae, distinguished four subfamilies within Trombidiidae : Allothrombiinae, Trombidiinae, Paratrombiinae and Dolichotrombiinae, but, due to the fragmentary, i.e. restricted to selected life instars, knowledge of some genera, she did not place 11 genera in any subfamily.

Cicaditrombium gen. nov. matches the diagnosis for Trombidiidae proposed by Welbourn (1984) (four setae on femur III, entire femora, five setae on tibia II, no solenidia on tibia III, scutellum present, naso absent, five setae on tibia III). However, the subfamilial placement is provisional. Based on Zhang (1995), the new genus fits best into Trombidiinae, rather than Allothrombiinae (adoral seta placed on tubular structure and ventral seta on palpal tarsus with reduced barbs) or other subfamilies established by Makol (2007). Also, the shape of the posterior end of the gnathosoma (not truncated), the setation on legs (one solenidion on Ge II) and idiosomal setation (h 2 much longer than others) as well as other above mentioned characters indicate that this species is a member of Trombidiinae.

Nevertheless, Cicaditrombium has some characters that make its placement in the Trombidiinae questionable. The absence of a famulus on Ta I and its presence on Ta II is unusual in Trombidioidea; all types were checked but the famulus was not seen on Ta I. Also, no Trombidiinae have supracoxal setae on the gnathosoma, but this seta is present in Allothrombiinae. These characters indicate that this species is more likely is related to one of the still "unassociated 11 taxa" of Makol (2007) rather than to Trombidiinae (Wohltmann, personal communication).

Cicaditrombium is similar to Azaritrombium , Oskootrombium and Iranitrombium in having Ge II and III with one solenidion, hypostomalae elongated and setulose and palp femur without setae. It differs from Azaritrombium by the posterior claw of Ta III short and thick (normally developed in Azaritrombium ), number of normal setae on Fe II (4 vs. 5), placement of setae on coxa II, punctation dispersion of scutum; shape of hypostomal seta, scutum and scutellum, adoral seta placed on projection, posterior seta on palp tibia smooth (setulose in Azaritrombium ), all dorsal and ventral setae on very small platelets (larger in Azaritrombium ) and solenidion on Ta I situated on 1/3 basal part of the segment; from Oskootrombium by the number of dorsal scuta (2 vs. 3), number of setae on coxa II (2 vs. 1), number of solenidia on Ge II (2 vs. 1), punctation dispersion of scutum; shape of hypostomal seta, scutum and scutellum, adoral seta placed on projection, all dorsal and ventral setae on very small platelets (larger in Oskootrombium ) and solenidion on Ta I situated on 1/3 basal part of the segment; from Iranitrombium by sensillae setulose distally (barbed along the stem in Iranitrombium ), number of normal setae on Ge I (4 vs. 5), number of dorsal scuta (2 vs. 3), number of solenidia on Ge II (2 vs. 1), punctation dispersion of scutum; shape of hypostomal seta and scutum, adoral seta placed on projection, all dorsal and ventral setae on very small platelets (larger in Iranitrombium ) and solenidion on Ta I situated on 1/3 basal part of the segment (situated about half-way in Iranitrombium ) and claw of Ta III short and thick (normally developed in Iranitrombium ).