1✉ Unit for Environmental Sciences and Management, North-West University, Potchefstroom Campus, Potchefstroom, 2520, South Africa.
2School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, South Africa.
3Department of Plant and Soil Sciences, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria, South Africa.
2022 - Volume: 62 Issue: 2 pages: 497-507https://doi.org/10.24349/a5f8-6nuj
The remarkable variation in South Africa's topography, climate, altitude and latitude has resulted in a diverse vegetation that is exceptionally rich with 11,690 plant taxa with 968 943 plant species on record in the national database (Powrie et al. 2012). As a result, South Africa boasts a wide range of vegetation biomes ranging from deserts to grasslands and forests (Mucina and Rutherford 2006). There are still many gaps and some areas of these biomes are still poorly known against predictions of plant diversity (Robertson & Baker, 2006). However, we have a limited understanding of the diversity of mites associated with plants with domatia in South Africa. Therefore, this paper is the second in a series to fill this knowledge gap and survey mite families associated with leaf domatia bearing plants (Situngu 2017). Leaf domatia are usually inhabited by mites and facilitate a protective mutualism between mites and the host plant (O'Dowd and Pemberton 1998; Norton et al. 2000; Romero and Benson 2005). Many studies have shown that these structures play a significant role in influencing mite assemblages found on plants with leaf domatia (Pemberton and Turner 1989; O'Dowd and Willson 1991; Walter and O'Dowd 1992; Walter 1996; Norton et al., 2000; Romero and Benson 2005; Situngu and Barker 2017). Leaf domatia alter the distribution, abundance, and reproduction of mites and the Tydeidae (Acari: Trombidiformes) are always significantly higher in domatia than on vein axils of plants lacking leaf domatia (O'Dowd and Willson 1991; O'Dowd and Pemberton 1998; Norton et al. 2000).
Kaźmierski (1996) described the monotypic genus Afridiolorryia based on A. africanus (Baker, 1965) collected from Afrocarpus usambarensis Pilg.C.N Page (Podocarpaceae) in the Democratic Republic of the Congo (Baker, 1965).
The objective of this study is to describe two new species and define the three other species of the family Tydeidae collected from woody species with domatia of the Eastern Cape, South Africa. This is part of a study carried out by the second author.
Field visits were undertaken to various forest types found in the Eastern and the Western Cape provinces periodically starting in January 2013 until October 2015. At each site, we conducted a thorough survey of trees with leaf domatia and herbarium voucher specimens of all the plants sampled were collected to verify the identity of the tree species, and to make sure all host plants were identified to species level. Some of the vouchers are housed at the Schonland Herbarium (GRA) in Grahamstown (now known as Makhanda). From each tree species that was found to possess leaf domatia, 20 leaves were collected and placed in a zip lock bag and stored in a cool backpack while in the field.
The leaves were examined for the presence of mites as soon after collection as possible (usually the same day they were collected) by viewing them under a dissecting microscope. All the mites found inside the domatia and the surrounding leaf blade were collected using a pipette and a drop of alcohol. Some were mounted on a stub and viewed under the Scanning Electron Microscope. Others were stored in a vial with alcohol and sent to the Biosystematics Division of ARC-Plant Health Protection Research for identification. The preserved mites were mounted on microscope slides in PVA and dried in an oven at 45–50 º Celsius for 24 hours. Line drawings were made from photographs of the specimens taken with a Zeiss Axioskop TM Research microscope equipped with an Axiocam 208 colour camera and a Zen Soft Imaging System with measuring tools. All illustrations were edited using Adobe Illustrator C5. Measurements in micrometers (μm) of the holotype are provided, followed by that of paratype female in parenthesis. For the dorsal setal notations Kaźmierski (1989a) is followed and for the venter, gnathosoma, leg setae and lyrifissures Andre (1981a, b). The taxonomic system of Andre & Fain (2000) is followed. The holotypes and paratypes will be deposited in the National Collection of Arachnida, ARC-Plant Health and Protection Research (NCA-PPRI), Pretoria, South-Africa.
Type-species Lorryia africanus Baker, 1965
Definition of genus as in Kaźmierski (1996)
Holotype female and one paratype female, on Psychotria capensis (Eckl.) Vatke, Rubiaceae, Kwelerha, 32.84° S, 26.94° E, near East London, 27 September 2014.
Dorsum — Length of idiosoma (excluding gnathosoma), 246 (257), length (including gnathosoma) 294 (296), width 184 (179). Body posteriorly bilobed. Dorsal shield covered with tubercles bordering faint polygonal cells and with 13 pairs of broadly lanceolate to leaflike and serrate setae except for bothridial setae bo which is filiform, smooth, rather stout and the longest and pointed distally but do not reach setae c1. Prodorsum recurved. Opisthosoma divided into 6 shieldlike areas. Lyrifissures not detectable amongst all the tubercles. Setal lengths: ro 15 (17), la 14 (16), bo 29 (27), ex 16 (17), c1 17, c2 16 (15), d 17, e 16 (16), f1 17(16), f2 18 (16), h1 17 (14), h2 15 (15), ps2 7 (10) (Fig. 1A-B).
Venter — Anogenital area damaged but with six pairs of genital setae and four pairs of aggenitals and one pair of pseudoanal setae (ps2). Venter finely striate and setae also very fine and not all of them distinct. Coxal organ oval. Epimeral formula: 3-1-4-2.
Gnathosoma — Setal pattern of palp (tarsus-genu): 6 (+ω)-1-2, tarsus with seta p′ζ blunt distally, d distally bifurcate and ba minute. Movable digit 24 (25) long and palptarsus 28 (26) long and slender, 8-14 times longer than wide, length of palp 45 (48) (femur to tip of tarsus, terminal setae excluded) (Fig. 2A-B).
Legs — Length of legs I-IV as follows (trochanter to empodium): leg I 86 (94), leg II 77 (75), leg III 69 (74) and leg IV 85 (79). All legs with two claws and a hairy empodium, with empodial claws. Solenidion ωI 10 (8) long, slender, bent and about half the width of the tarsus, seta k″ on tibia I minute. Setae l″ on tibia and genu I scoop like and serrate. Tarsus I with ft′ and ft″ slightly serrate and equal in length but shorter than tc′ and tc″. Tarsus II with ωII, 4 (4) long. Seta on genu II scoop like and serrate. Leg formulae as follows (tarsus -trochanter): Leg I: 8(1ω)-3(1k)-2-3-0; Leg II: 6(1ω)-1-1-2-0; Leg III: 5-1-1-1-1; Leg IV: 5-1-1-1-0 (Fig. 2 C-D).
This species is named after the genus name of the host plant.
This species differs from the type species A. africanus (Baker) in that setae tc′ and tc″ and ft′and ft″ on tarsus I are not equal in length and smooth, but ft′ and ft″ are shorter and slightly serrate in A. psychtriae sp. n., solenidion ωI on the tarsus are bend in the new species but straight in A. africanus. Seta l′ on tibia I are scoop like in the new species but long, smooth and simple in A. africanus. This species differs from A. kwelerhaensis sp. n. in that the dorsal setae are similar in shape and length, except setae bo, oppose to all setae (bo excluded) being long, lanceolate, serrate except for setae e, f1-2 and h1-2 which are club-shape and smooth in A. kwelerhaensis sp. n. The shape of setae l′ on tibia and genu I, seta on genu II and solenidion ωI also differs between the two new species, the leg setae being scoop like and the ωI bent in A. psychotriae sp. n. but broadly lanceolate and ωI straight in A. kwelerhaensis sp. n.
Holotype female, on P. capensis, Kwelerha, 32.84° S, 26.94° E, near East London, 27 September 2014.
Dorsum — Length of idiosoma (excluding gnathosoma), 248, length (including gnathosoma) 296, width 179. Body slightly bilobed posteriorly. Dorsum completely covered with tubercles bordering faint polygonal cells and with 13 pairs of long, lanceolate, serrate setae except for bothridial setae bo which is filiform, smooth, rather stout and the longest and pointed distally and setae e, f1-2 and h1-2 which are club-shape and smooth. Setae bo reach pass setae c1. Prodorsum recurved. Opisthosoma divided into 5 shieldlike areas. Lyrifissures are camouflaged by the granules. Setal lengths: ro 25, la 25, bo 44, ex 28, c1 25, c2 24, d 22, e 21, f1 18, f2 20, h1 19, h2 16, ps2 10 (Fig. 3A-B).
Venter — Anogenital area with six pairs of genital setae and four pairs of aggenitals and one pair of pseudoanal setae (ps2). Venter finely striate with striae longitudinal between setae mtα and mtβ. Coxal organ oval. Epimeral formula: 3-1-4-2 (Fig. 4A).
Gnathosoma — Setal pattern of palp (tarsus-genu): 6 (+ω)-1-2, tarsus with seta p′ζ blunt distally, d distally bifurcate and ba minute. Movable digit 25 long and palptarsus 27 long and slender, 16 times longer than wide, length of palp 49 (femur to tip of tarsus, terminal setae excluded) (Fig. 4B-C).
Legs — Length of legs I-IV as follows (trochanter to empodium): leg I 109, leg II 97, leg III 109 and leg IV 115. All legs with two claws and a hairy empodium, with empodial claws. Solenidion ωI 6 long, slender, straight and about half the width of the tarsus, seta k″ on tibia I minute. Setae l′ on tibia and genu I broadly lanceolate and serrate. Tarsus I with ft′ and ft″ slightly serrate and equal in length but shorter than tc′ and tc″. Tarsus II with ωII, 3 long. Seta on genu II stout, curved and serrate. Leg formulae as follows (tarsus -trochanter): Leg I: 8(1ω)-3(1k)-2-3-0; Leg II: 6(1ω)-1-1-2-0; Leg III: 5-1-1-1-1; Leg IV: 5-1-1-1-0 (Fig. 5A-C).
This species is named after the type locality.
Differences between the two new species and the type species as discussed under A. psychotriae sp. n. However, solenidion ωI is also straight as in A. africnaus sp. n.
Tydeus munsteri Meyer & Ryke, 1959: 413; Ryke & Meyer, 1960: 266; Meyer & Rodrigues, 1966: 22; Kaźmierski, 1989b: 293; Kaźmierski, 1998: 341; Ueckermann & Grout, 2007: 2362; Da Silva et al., 2016: 38.
Tydeus (Afrotydeus) munsteri (Meyer & Ryke), Baker, 1970: 165.
Orthotydeus munsteri (Meyer & Ryke), Andre, 1980: 128.
Material examined — 4 ♀ Alexandria Forest, on Ehretia rigida (Thunb.) Druce (Boraginaceae), 28 August 2014; 2 ♀ Alexandria Forest, on Grewia occidentalis L. (Malvaceae), 28 August 2014; 2 ♀, one ♂, Gunubie, East London, on G. occidentalis, 26 September 2014; Kwelerha, East London, on Rhoicissus digitata (L.f.) Gilg & M. Brandt (Vitaceae), 27 September 2014; 4 ♀, Stellenbosch, Tecomaria capensis (Thunb.) Spach (Bignoniaceae), 11 November 2014; 5 ♀ from Grahamstown, on Coprosma repens A. Rich (Rubiaceae), October 2014.
This species is characterized by the following combination of characters: all dorsal setae, except for ro and la, short and leaf-like and pointed distally, ex also appear pointed distally in some specimens. Setae bo longest and slightly spatulate distally.
World distribution — South Africa, Eswatini, Mozambique, Florida USA. This species was sampled 28 times since description, present study included (Meyer & Ryke, 1959, Ryke & Meyer, 1960, Meyer & Rodrigues, 1966, Baker, 1970 and Ueckermann & Grout, 2007).
Tydeus grabouwi Meyer & Ryke, 1959: 410; Ueckermann & Smith Meyer, 1988: 32; Kaźmierski, 1989b: 293; Kaźmierski, 1998: 344; Ueckermann & Grout, 2007: 2365; Da Silva et al., 2016: 36.
Material examined — 3 ♀ Alexandria Forest, on Rhoicissus tomentosa (Lam.) Wild & R.B. Drumm (Vitaceae), 28 August 2014; 4 ♀ Stellenbosch, on Erhetia sp. (Boraginaceae), 11 November 2014; 2♀, 2♂ Hogsback, on Berchellia sp. (Rubiaceae), 10 October 2014
3♀Alexandria Forest, on R. tomentosa, 28 August 2014; 4 ♀ Stellenbosch, on Erhetia sp. (Boraginaceae), 11 November 2014; 2♀, 2♂ Hogsback, on Berchellia sp. (Rubiaceae), 10 October 2014.
This species can be recognized by having four pairs of lanceolate/clavate setae, f2, h1–2, and ps1, caudally on opisthosoma.
World distribution — South Africa. This species regularly occurs in samples from the Western and Eastern Cape Provinces.
Orfareptydeus stephani Ueckermann & Grout, 2007: 2358
Material examined — 3 ♀ Alexandria Forest, on G. occidentalis (Malvaceae), 28 August 2014.
The unique chaetotaxy of the leg femora and trochanters, namely 2-1-0-0 and 1-0-0-0, respectively distinguishes this species, the type species of the monotypic genus Orfareptydeus.
World distribution —This is the second record of this species after its description and therefore only known from South Africa.
Key to species of the Tydeidae on plants with leaf domatia in the Eastern Cape and the species of the genus Afridiolorryia — Females.
1. Femora I-IV with 3-2-1-1 setae
— Femora I-IV with 2-1-0-0 setae
...... Orfareptydeus stephani Ueckermann & Grout
2. Genua I-IV with 3-2-1-1- setae; tibiae I-IV with 4-2-2-2 setae
...... Tydeus Koch – 3
— Genua I-IV with 2-1-1-1- setae; tibiae I-IV with 4-1-1-1 setae
...... Afridiolorryia Kaźmierski – 4
3. All dorsal setae except bo, ro and la short, leaf-like and pointed
...... T. munsteri Meyer & Ryke
— Setae f2, h1–2, and ps1 lanceolate/clavate
...... T. grabouwi Meyer & Ryke
4. Solenidion ωI straight
— Solenidion ωI bent
...... A. psychotriae sp. n.
5. Setae tc′ and tc″ and ft′ and ft″ on tarsus I long, smooth and simple and almost equally long; seta l′ on tibia I also long smooth and simple
...... A. africanus (Baker)
— Setae tc′ and tc″ and ft′and ft″ on tarsus I not equally long, latter setae shorter and slightly serrate; seta l′ on tibia I broadly lanceolate and serrate
...... A. kweleraensis sp. n.
The authors wish to thank the Centre of Excellence in Tree Health and Biotechnology (CTHB) and the Green Matter Fellowship, for providing funding for the forest visits and offering career development opportunities.
This work is based on the research supported wholly / in part by the National Research Foundation of South Africa (Grant Numbers 126938). Any opinion, findings and conclusions or recommendations expressed in the material are those of the authors and therefore the NRF does not accept any liability in regard thereto.
The authors report no declarations of interest.