Favognathus insularis ( Luxton, 1973 )

Paktinat-Saeij, Saeid, Bagheri, Mohammad & Damavandian, Mohammad Reza, 2020, Redescription of Favognathus insularis (Luxton) (Acari: Trombidiformes: Cryptognathidae) from Brazil, with a key to the world species of Favognathus, Persian Journal of Acarology 9 (1), pp. 13-21 : 14-17

Favognathus insularis ( Luxton, 1973)

( Figs. 1–9 )

Cryptognathus insularis - Luxton, 1973: 64.

Favognathus insularis (Luxton) - Luxton, 1987: 113; Krisper and Schneider 1998: 201; Doğan, 2008: 1677.

Diagnosis

Anterior margin of the hood smooth; dorsal and ventral shield laterally ornamented with reticulations; reticular cells with 4–6 peripheral pores and short striae; dorsoventrally with four slitlike cupules; dorsum with one pair of cluster associated with setae d1; intercoxal area smooth; femora I–IV: 4–3–2–2; genua I–IV: 5(+ κ)–4(+ κ)–2–3 tarsi I–IV: 15(+ ω 1+ ω 2)–12(+ ω 1+ ω 2)–9(+ ω)–9(+ ω).

Distribution

Niue Island ( Luxton 1973); Brazil (in this study).

Description

Female (n = 4) – Red-colored while alive. Length of body 260–283; Length of subcapitulum 87–97; width of body: 144–180; leg I: 198–221, leg II: 161–179, leg III: 142–165, leg IV: 180–191.

Dorsum ( Fig. 1 ) – Anterior margin of the hood smooth; hood with 6–7 dimples in each longitudinal row. Dorsal shield ornamented with pores, evenly distributed, lateral parts of dorsal shield reticulated; central area of dorsum with punctuations and striations ( Fig. 1 , B); reticulate pattern formed by cells, each bearing 4–6 pores periphery and pores distributed evenly in all reticulation cells; short striae; dorsum with 11 pairs of simple setae, one pair of eyes and one pair of postocular bodies laterally between setae sci and sce; dorsal body with three pairs of slit-like cupules as follows: ia between setae sce and c1, im beside setae e2 and ip beside setae h2; a cluster of reticulated cells associated with setae d1 present, these rosette patterns consist of four cells; anal opening dorsoventrally, with three pairs of setae (ps 1–3). Length of dorsal setae and their distances: vi 13–14; ve 21–25; sci 17–19; c 1: 25–28; sce: 22–25; d 1: 26–30; e 1: 26–29; e 2: 22–27; f 1: 25–28; h 1: 23–26; h 2: 18–20; vi–vi: 32–38; vi–ve: 8–10; ve–ve: 32–37; sci–sci: 49–53; sci–sce: 21–32; c1–c1: 56–60; sce – sce 84–100; c1–d1 45–49; d1–d1: 100–110; d1–e1: 34–42; e1–e1: 68–72; e2–e2: 93–96; e1–f1: 41–42; f1– f 1: 33–38; f 1 –h 1: 28–32; f 1 –h 2: 36–40; h 1 –h 1: 14–19; h 1 –h 2 21–29; h 2 –h 2: 68–72.

Venter ( Fig. 2 ) – Prosternal apron wedge-shaped with 15–18 foveolae; venter with three pairs of ventral setae (1a, 3a and 4a); genital opening with two pairs of genital (g1–2) and three pairs of aggenital (ag1–3) setae; ventral shield with lateral reticulations, fine striae and pores, intercoxal area smooth and with a longitudinal row of pores; venter with cupule ih. Length of ventral setae: 1a 11– 12, 3a 12–13, 4a 11–13, ag 1 9–10, ag 2 9–10, ag 3 8–9, g 1 10–11, g 2 10–11; ps 1 11–13, ps 2 10–11, ps 3 8–10.

Gnathosoma ( Figs. 3–5 ) – Hypostome narrow ( Fig. 4 ), with one pair of long setae m 22–27 and two pairs of adoral setae, or 1 4–5, or 2 7–8 ( Fig. 4 ); chelicerae 84–90; ( Fig. 5 ); palp ( Fig. 3 ) 80–91 long, palptarsus with four eupathidia, four simple setae and one solenidion; palptibia with three simple setae; palpgenu with two and palpfemur with three simple setae. Palp trochanter without setae.

Legs ( Figs. 6–9 ) – Setal formulae of leg segments (solenidia in parentheses and not included): coxae 2–1–2–1; trochanters 1–1–2–1; femora 4–3–2–2; genua 5(+ κ)–4(+ κ)–2–3; tibiae 5(+ φ + φp)– 5(+ φp)–4(+ φp)–3; tarsi 15(+ ω 1+ ω 2)–12(+ ω 1+ ω 2)–9(+ ω 1)–9(+ ω 1).

Male and immature stages – Unknown.

Material examined

Four females from soil and rotten leaves, collected on September 28, 2015 at Piracicaba , state of São Paulo, Brazil by Saeid Paktinat-Saeij. All specimens are deposited in the Acarological Collection, Department of Plant Protection , Faculty of Agriculture, University of Maragheh, Maragheh, Iran.

Remarks

The original description of this species is incomplete and insufficiently illustrated. The Brazilian specimens show all characters of the original description but with more details. Herein, we provide the only description of this species containing complete details with legs setal number which is missed in previous ones. The morphological characteristics and general appearance of the Brazilian specimens are similar to those of the original description of Luxton (1973). However, it differs from newly found specimens in length and width of dorsal shield and length of some dorsal setae of which are longer than those of the original description, for example: length of dorsal setae d 1 26–30, e 1 26 – 29, f 1 25–28 in Brazilian specimens versus d 1 22, e 1 26, f 1 22 in original description. Furthermore prosternal apron with 15–18 foveolae versus 14 foveolae in specimens collected by Luxton (1973).

Flechtmann (1971) mentioned the family Cryptognathidae in his unpublished thesis and described a new species as Cryptognathus agapictus Flechtmann, 1971 ( Favognathus agapictus ( Flechtmann, 1971) , since it is not published, according to ICZN - Article 8, C. agapictus is an invalid species. Based on similarity of the characters and descriptions of these specimens, it seems that they are conspecific.

Figures

Figures 1–5. Favognathus insularis (Luxton, 1973) (female) – 1. Dorsal view of idiosoma; 2. Ventral view of idiosoma; 3. Palp; 4. Subcapitulum; 5. Chelicera.

Figures 6–9. Favognathus insularis (Luxton, 1973) (female) – 6. Leg I; 7. Leg II; 8. Leg III; 9. Leg IV.