Spinibdella trinomma, Theron, Elizabeth Omukunda Pieter D & Ueckermann, E A, 2012

Theron, Elizabeth Omukunda Pieter D & Ueckermann, E A, 2012, Spinibdella Thor (Acari: Bdellidae) from southern Africa: descriptions of five new species and the redescription of S. thori (Meyer & Ryke), Zootaxa 3304, pp. 1-24 : 3-6

Spinibdella trinomma sp. nov. Omukunda, Theron & Ueckermann

Figs. 1–10

Description. Female (n=1). Dimensions: Length of idiosoma (gnathosoma included) 915; width 405; length of gnathosoma 172; length of chelicerae 153; length of DHS 12; length of palp segments: I 10; II + III 109; IV 12; V 33; des 145; ves 101; length of legs: I 237; II 210; III 304; IV 345; length of setae: vi 70; ve 32; sce 34; sci broken off; c1 31; c2 40; d 31; e 31; f1 33; f2 broken off; h1 37; h2 38; distance: vi-vi, 34; first interspace (c1 to d), 71.

Gnathosoma ( Figs 1–3 ). Chelicerae have fine continuous longitudinal striations and a pair of strong setae each inserted as shown in figure 1. Movable digit straight and slightly longer than fixed digit. Palps ( Fig. 2 ) extend beyond hypostome. Palp tibiotarsus three times longer than genu. Palp chaetotaxy as follows: from trochanter to tibiotarsus: 0-8-1-4-3 sts; 1ω, 1 des; 1 ves. Hypostome with continuous to sparsely broken longitudinal striations with fine continuous transverse striations at base. Two pairs of prominent setae inserted as shown in figure 3. DHS setae short (12), two pairs of adoral setae present.

Dorsum ( Figs 4–5 ). Reduced simple naso with a hemispherical median eye posterior to it. Setae vi thin, ve nude and thin in anterior half of podosoma, sce thick and pilose, sci broken off in this specimen. Centre of prodorsum transversely striated whereas lateral margins longitudinally striated. Anterolaterally a pair of detectable eyes, with striae in shape of a teardrop where posterior pair of eyes are supposed to be situated. ( Fig. 4 ). Transverse striations separate anterior pair of eyes and posterior region. Except for vi, ve and sce, all other dorsal setae pilose. Setae c1 about ½ first interspace. Dorsal striation pattern as shown in figure 5. Sejugal groove distinct.

Venter ( Figs 6–7 ). Ventral setae nude except ps1–3 which are pilose. Venter bears 28 blunt aggenitals, two unpaired setae between coxae III. Genital plates have nine blunt genital setae each linearly arranged as shown in figure 6. Ovipositor ( Fig. 7 ) has 12 subapical and six medial setae. Anal valves bordered by three pairs of pilose anal setae (ps1–3), and parallel striations. Striation pattern of venter continuous as shown in figure 6.

Legs ( Figs 8–9 ). Legs shorter than idiosoma. All femora divided. Tactile setae on legs I and II nude while on III and IV both pilose and nude. Trichobothria on legs relatively short. Duplex setae on genua I–III have insertion contiguous and situated medially. Tibia I has in distal half two attenuate solenidia, one relatively short, solid attenuate peg and a trichobothrium ( Fig. 8 ). Tibia II has a deeply recessed blunt solenidion distally as seen in figure 9 and tibia III an attenuate solenidion in same position. Tibia IV has a trichobothrium in median position. Tarsus I has a proximal attenuate solenidion; two blunt solenidia in distal half. Tarsus II has a solid simple peg in proximal half; two blunt solenidia in distal half. Tarsus III has a proximal trichobothrium. Tarsus IV has trichobothrium as in III.

Claws rayed and shorter than pretarsi. Basifemur, telofemur and genu III and IV each have a branched macroseta. Some tactile setae branched. Leg chaetotaxy as follows: coxae I–IV 10-8-7 -6 sts; trochanters I–IV 1-1 -2-1 sts; basifemora I–IV 6-7 -6-3 sts; telofemora I–IV 5-5 -4(6)-5 sts; genua I–IV 5 sts, 1 duplex - 6 sts, 1 duplex - 6 sts, 1 duplex. - 7 sts; tibiae I-IV 11 sts, 2φ, 1ĸ, 1tr -11 sts, 1 recessed blunt ϕ - 11sts, 1φ - 11sts, 1tr; tarsi I-IV 24 sts, 3ω - 24 sts, 2ω, 1 ĸ -21 sts, 1 tr - 23(22) sts, 1 tr.

Male. ( Fig. 10 ) (n=3). Dimensions: Length of body including gnathosoma, 777–867; width 353; length of gnathosoma 168–179; DHS, 8–12; length of palp segments: I 10; II + III 97 –162; IV 13–15; V 33 –36; des 145–166; ves 97–113; length of chelicerae 143–152; length of leg: I 210–245; II 220–250; III 288–315; IV 332; length of setae: vi broken off; ve, 33–42; sci, broken off; sce 36–38; c1 34–38; c2 42–48; d 34–36; e 34–35; f 1 29–34; f2 38; h1 39; h2 43–45; distance: vi– vi 28–38; first interspace (c1 to d) 57–65.

Male differs from female in following aspects: 12 pairs of genital setae instead of nine pairs and presence of amphioid sclerites ( Fig. 10 ) characteristic of this species. Leg chaetotaxy as follows: coxae I–IV 10-8-7 -6 sts; trochanters I–IV 1-1 -2-1 sts; basifemora I–IV 7-8 -7-3 sts; telofemora I–IV 5-5 -4-5 sts; genua I–IV 5 sts, 1 duplex.- 6 sts, 1 duplex - 6 sts, 1 duplex. - 7 sts; tibiae I-IV 12 sts, 2φ, 1ĸ, 1tr -13 sts, 1 recessed blunt ϕ - 12sts, 1φ - 12sts, 1tr; tarsi I–IV 25 sts, 3ω - 23 sts, 2ω, 1 ĸ - 25 sts, 1 tr - 21 sts, 1 tr.

Tritonymph (n=1). Dimensions: length including gnathosoma 659; width 294; length of gnathosoma 143; length of chelicerae 132; length of DHS 10; length of palp segments: I 10; II + III 88; IV 13; V 29; des 122; ves 80; length of legs: I 163; II 159; III 223; IV 259; length of setae: vi 65; ve 27; sci broken off; sce 31; c1 29; c2 39; d 29; e 29; f1 27; f2 30; h1 34; h2 35; distance vi– vi 34; interspace (c1 to d) 61.

This developmental stage has three pairs of genital discs with anterior pair larger than posterior two. Five pairs of genital setae and seven pairs of aggenital setae. Both genital and aggenital setae blunt. Anterior unpaired aggenital seta occurs between coxae III while next one lies between coxae IV. Ecdysial line present. Palp basifemur has six setae. Other segments similar to that of female. Legs I and II have nude setae while III and IV have both nude and pilose setae. Leg chaetotaxy differs from that of female as follows: coxae I–IV 8-6 -6-4 sts; trochanters I–IV 1- 1 -2-1 sts; basifemora I–IV 6-7 (6)-5-4 sts; telofemora I–IV 4-3 -4-4 sts; genua I–IV 3 sts, 1 duplex - 4 sts, 1 duplex - 4 sts, 1 duplex - 5 sts; tibiae I-IV 8 sts, 2φ, 1ĸ, 1tr - 9 sts, 1 recessed blunt ϕ - 8sts, 1φ - 8 sts, 1tr; tarsi I–IV 20 sts, 3ω – 20 sts, 2ω, 1 ĸ – 19 sts, 1 tr – 18(20) sts, 1 tr.

Type material. SOUTH AFRICA, KwaZulu/ Natal Province: Holotype female, from Spirostachys africana, Sond. (Euphorbiaceae) 16 km north of Hluhluwe, 21 August 1980, Coll. M.K.P. Smith Meyer; three male paratypes from soil under Acacia karroo Hayne (Fabaceae) . North–West Province: North-West University, Potchefstroom Campus, 6 July 1971 and 3 August 1998, J. van Huyssteen and E. Omukunda; one tritonymph paratype, from Rubia horrida (Thunb.) Puff (Plantaginaceae) , Roodeplaat near Pretoria, Gauteng, 15 January 1980, Coll. M.K.P. Meyer.

Etymology. Trinus, Latin for three and omma, Greek for eyes. Name signifies three eyes in this species.

Differential diagnosis. This species resembles S. depressa (Ewing) in most respects: the striae forming a teardrop where the posterior eyes are supposed to be, setae ve approximate to vi, blunt solenidion on tibia II deeply recessed and the palp and leg chaetotaxy. S. trinomma only differs in the presence of an anterior median eye and the shape and number of eugenital setae of the male; the first group of eugenital setae (4 instead of five pairs) of the male is branched, the second group has three branched setae instead of two. According to Atyeo (1960) only the males of Spinibdella and Cyta display striking enough differences to warrant their use as taxonomic characters.

Figures

FIGURES 1 – 7. Spinibdella trinomma sp. n.: 1. Female chelicera; 2. Female palp; 3. Female hypostome; 4. Female prodorsum; 5. Female dorsal view; 6. Female ventral view; 7. Female ovipositor.

FIGURES 8 – 10. Spinibdella trinomma sp. n.: 8. Female leg I; 9. Female leg II; 10. Male genitalia.