Tydeus munsteri Meyer and Ryke

Ueckermann, Edward A. & Grout, Timothy G., 2007, Tydeoid mites (Acari: Tydeidae, Edbakerellidae, Iolinidae) occurring on Citrus in southern Africa, Journal of Natural History 41 (37 - 40), pp. 2351-2378 : 2362-2365

Tydeus munsteri Meyer and Ryke

Tydeus munsteri Meyer and Ryke 1959, p 413 ; Meyer and Rodriques 1966, p 22; Kaźmierski 1989, p 293.

Tydeus (Afrotydeus) munsteri Meyer and Ryke ; Baker 1970, p 165.

Orthotydeus munsteri (Meyer and Ryke) ; André 1980, p 127.

Material examined

South Africa: Mpumalanga Province: one female, four males, and three tritonymphs from Citrus sp., Lowveld Agricultural College, Nelspruit (25 ° 26.39S, 30 ° 58.89E), 14 August 2002, T. G. Grout . Northern Cape Province: three females and one male from Citrus sp., Kuruman (27 ° 26.69S, 23 ° 25.69E), 13 May 2003, T. G. Grout .

Meyer and Rodrigues (1966) also recorded this species on citrus from Grahamstown (Eastern Cape Province), Buffelspoort (North-West Province), Kiepersol (Mpumalanga), Durban and Richmond (KwaZulu-Natal), and Swaziland.

Diagnosis

Adults. For an unknown reason Baker (1970) placed this species in his subgenus T. (Afrotydeus), with four pairs of genital setae, in spite of the fact that Meyer and Ryke (1959) clearly stated that T. munsteri has the same number of genital setae as T. grabouaei Meyer and Ryke , namely six. Perhaps the type specimen he studied was a tritonymph.

This species is characterized by the following combination of characters: all dorsal setae, except for υi and υe, short and spatulate and pointed distally, sce also appear pointed distally in some specimens. Setae sci longest and slightly spatulate distally.

Tydeus spathulatus (Oudemans)

( Figures 13–19 )

Tydeus spathulatus Oudemans 1928, p 380 . Tetranychoides californicus Banks 1904, p 54 . New synonym?

Material examined

Zimbabwe: two females and one tritonymph, from Citrus sp., southwest of Mvurwi, Arda farm (17 ° 10.69S, 30 ° 56.99E), 5 August 2003, T. G. Grout; five females, from Citrus sp. 5 km northeast of Mvurwi, Egdon farm, 5 August 2003, T. G. Grout; one female from Citrus sp., southwest of Mvurwi, Gem farm (17 ° 15.39S, 30 ° 53.19E). Israel: two females, one male, and one tritonymph from Carya illioensis, Ashdot Ya’acow, Jordan Valley (31 ° 45.09N, 34 ° 40.09E), 14 December 1976, H. N. Plaut.

Accession numbers: AcY: 03/276-278 and 78/134.

Diagnosis

Adults. The presence of five pairs of spatulate setae (e 1–2, f 1–2, and h 1) on the opisthosoma characterized this species.

Female (n59). Dimensions of Zimbabwean specimens with those of the Israeli specimens in parentheses: length of idiosoma 347–438 (359–410), width 217–302 (205–280); legs: I 239–267, II 214–239, III 221–233, IV 201 268–233; setae: υi 19–25 (25), υe 22–28 (28– 32), sci 25–38 (35–38), sce 25–32 (32), c 1 19–28 (28), c 2 25–32 (35), d 1 19–28 (25–32), d 2 25–32 (35), e 1 25–32 (35), e 2 28–35 (32), f 1 28–32 (33–35), f 2 28–32 (32–35); h 1 25–28 (28–32), ps 19–22 (22); cheliceral stylets 16–19 (19); palptarsus 22–25 (25).

Dorsum ( Figures 13–15 ): all dorsal setae slightly serrated ( Figure 14 ), except for setae e 1–2, f 1–2, and h 1 which are spatulate ( Figure 15 ) and serrate; however, d 2 can also be spatulate in some specimens. Setae sci slightly longer than other dorsal setae. Prodorsum with four pairs of setae, opisthosoma with nine, only cupule ia could be detected. Striae with minute spikelike tubercles. Striae longitudinal on propodosoma and transverse medially on opisthosoma.

Venter ( Figure 16 ): epimeral formula 3-1-4-2. Genital area with four pairs of aggenital and six genital setae and no eugenital setae. Striae immediately lateral to progenital opening smooth, not tuberculated. Only one pair of anal setae (ps) present and paraproctal suckers well developed. Cupule ih lateral to paraproctal suckers.

Gnathosoma ( Figure 17 ): palp chaetotaxy (tarsus to trochanter): 6(ω)-2-2-0. Setae ba shortest, solenidion ω minute.

Legs ( Figures 18, 19 ): chaetotaxy of leg segments: tarsi 8(ω)-6(ω)-5-5, tibiae 4-2-2-2, genua 3-2-1-1, femora 3-2-1-1, trochantera 1-0-1-0. Femur IV entire. All tarsi terminate in two claws and a hairy empodium. Coxa I with coxal organ.

Male (n51). Dimensions of Israeli specimen: length of idiosoma (including gnathosoma) 315, width 192; setae: υi 22, υe 25, sci 33, sce 32, c 1 28, c 2 32, d 1 28, d 2 28, e 1 28, e 2 28, f 1 32, f 2 28, 16, h 25, ps 22; cheliceral stylets 19; palp tarsus 23.

Similar to female but differs in that the genital area has four pairs of aggenital, six pairs of genital, and four pairs of eugenital setae. Paraproctal suckers well developed. Coxa I with coxal organ.

Tritonymph (n52). Dimensions (measurement of Israeli specimen in parentheses): length of idiosoma (including gnathosoma) 265 (302), width 173 (180); legs: I 199 (183), II 177 (170), III 157 (151), IV 173 (173); setae: υi 16 (19), υe 19 (19), sci 28 (?), sce 22 (25), c 1 16 (22), c 2 22 (25), d 1 19 (22), d 2 22 (25), e 1 22 (25), e 2 22 (28), f 1 22 (25), f 2 22 (25), h 16 (22), ps 16 (19); cheliceral stylets 13; palp tarsus 22.

Tritonymph differs from adults by lacking a progenital aperture, which is represented by two pores, presence of four pairs of aggenital, three pairs of genital, and one pair of anal setae. Paraproctal suckers well developed. Coxa I with coxal organ.

Remarks

The South African specimens resemble the redescription of T. spathulatus ( André 2005) in all respects. Tydeus californicus (Banks) may be a junior synonym of T. spathulatus because it corresponds to the redescription of the latter in all respects; five pairs of lanceolate/clavate dorsal setae posteriorly, striae arrangement of genital area and blunt setae on genua III and IV. This is a new record for South Africa. Figures 20 and 21 show how the setae of T. grabouaei Meyer and Ryke , the closely related South Africa species, differ from that of T. spathulatus .

Figures

Figures 13–21. (13–19) Tydeus spathulatus Oudemans, female. (20, 21) Tydeus grabouaei Meyer and Ryke. (13) Dorsum leg II. (14) Seta d2. (15) Seta e1. (16) Venter. (17) Palp. (18) Leg I. (19) Leg II. (20) Seta d1. (21) Seta e2.