Schoengastia scincicola Lawrence, 1949

Stekolnikov, Alexandr A., 2024, Revision of South African chiggers (Acariformes: Trombiculidae) originated from the collection of R. F. Lawrence, with redescriptions of nine species, Zootaxa 5493 (1), pp. 1-35 : 20-23

Schoengastia scincicola Lawrence, 1949

( Figs. 10 , 11 )

Schoengastia scincicola Lawrence, 1949: 427 , fig. 14; Wharton & Fuller 1952: 89; Vercammen-Grandjean 1958b: 659, pl. 9; Stekolnikov 2018: 88 .

Schoengastia (Schoengastia) scincicola : Zumpt 1961: 159; Vercammen-Grandjean 1965b: 82.

Diagnosis. SIF = 7BS-N-3-3111.1000; fPp = b/N/NNN; AL> PL >> AM; fD = 2H-8-6-6-4+(4–6); DS = 30–32; V = 24–25; NDV = 55–56; scutum pentagonal, with greatly projected rounded posterior margin; sensillary bases anterior to level of PLs; Ip = 823–850. Standard measurements are given in Table 6 .

Redescription (holotype, 2 paratypes, and 1 non-type specimen). IDIOSOMA ( Figs. 10 , 11A–F ). Eyes 2 + 2, in ocular plate; 30–32 dorsal idiosomal setae, including one pair of humeral setae, moderately barbed, 8 setae in 1 st posthumeral row (C excluding humeral setae), by 6 setae in next two rows (D and E), four setae in 4 th row (F) plus 4–6 caudal setae; 4 sternal setae; 24–25 ventral setae; NDV = 55–56.

GNATHOSOMA ( Fig. 11G–I ). Cheliceral blade with tricuspid cap and row of 5–6 dorsal teeth; cheliceral base with sparse puncta; gnathobase with sparse puncta, transverse cuticular striations and one pair of branched gnathocoxal (tritorostral) setae; galeal (deutorostral) seta nude; palpal claw with three prongs; seta on palpal femur with one branch (visible only in one specimen); setae on palpal genu and tibia nude; palpal tarsus with 7 branched setae, subterminala (ζ) and tarsala (ω).

SCUTUM ( Figs. 10 , 11C ). Pentagonal, moderately covered with small puncta, anterior scutal margin slightly concave, lateral margins almost straight, posterior margin greatly projected, rounded; AM posterior to level of ALs; sensillary (trichobothrial) bases anterior to level of PLs (PSB – P-PL = 2–6), with curved anterior ridges; AM uniform with dorsal idiosomal setae, ALs and PLs covered with long thin barbs; AL> PL >> AM; sensilla (trichobothria) globose, covered with setules.

LEGS ( Fig. 11J–L ). All 7-segmented, with 1 pair of claws and claw-like empodium. Leg I: coxa with 1 branched seta (1B); trochanter 1B; basifemur 1B; telofemur 5B; genu 4B, 3 genualae (σ), microgenuala (κ); tibia 8B, 2 tibialae (φ), microtibiala (κ); tarsus 21B, tarsala (ω), microtarsala (ε) distal to tarsala, subterminala (ζ), parasubterminala (z), pretarsala (ζ). Leg II: coxa 1B; trochanter 1B; basifemur 2B; telofemur 4B; genu 3B, genuala (σ); tibia 6B, 2 tibialae (φ); tarsus 16B, tarsala (ω), microtarsala (ε) behind tarsala, pretarsala (ζ). Leg III: coxa 1B; trochanter 1B; basifemur 2B; telofemur 3B; genu 3B, genuala (σ); tibia 6B, tibiala (φ); tarsus 14B, mastitarsala.

Distribution and hosts. This species was described from Vumba and Chishawasha, Southern Rhodesia (currently Zimbabwe), ex Trachylepis varia (Peters) (syn. Mabuya varia ) ( Squamata: Scincidae ). Here I report it from South Africa (Drakensberg Mts, Champagne Castle, KwaZulu-Natal Prov.) and ex Pseudocordylus subviridis (Smith) ( Squamata: Cordylidae ) for the first time.

Material examined. Holotype, larva NM 4870, Vumba, S. Rhodesia, ex M. varia , February 1948, collector unknown ( Fig. 1 , 16 ). One paratype, larva NM 4870/2, same data ( Fig. 1 , 17 ). One paratype, larva deposited in NHM (1957-8-12 -35), same data ( Fig. 1 , 18 ). One larva NM 4870/3, Champagne Castle , Hostel , Natal (currently KwaZulu-Natal Prov.), ex P. subviridis , collector and date unknown ( Fig. 1 , 19).

Remarks. The specimen of S. scincicola NM 4870/3 from Champagne Castle ( Fig. 1 , 19) and the specimen of S. monticola NM 4827 from Vumba ( Fig. 1 , 22) have an inscription “ paratype ”, but their collection data do not coincide with the original description and the identification labels seem not original. Probably, these specimens were re-identified and renumbered; therefore, I cannot regard them as true paratypes. I assume that the former initially belonged to the type series of S. monticola and the latter—to the type series of S. scincicola .

Figures

FIGURE 1. Slide labels. 1, Microtrombicula homopholis, holotype; 2, Hypotrombidium subquadratum, holotype; 3, Willmannium natalense, lectotype; 4, W. natalense, paralectotype 1; 5, M. nivaria, paratype; 6, Herpetacarus (Abonnencia) alticolus, holotype; 7, H. (A.) alticolus, paratype; 8, H. (A.) alticolus, slide with topotypic specimens; 9, H. (A.) africanus, holotype; 10, H. (A.) africanus, topotypic specimen (ZIN label is on the opposite side); 11, H. (A.) longispinus, holotype; 12, H. (A.) longispinus, topotypic specimen (ZIN label is on the opposite side); 13, Ascoschoengastia rhabdomyia, slide NM 5387; 14, Riedlinia (Trombigastia) cadei, specimen NM 6544/3 (pencil inscription “/3” is mine; my identification label is on the opposite side); 15, Schoengastia pseudocordyli, slide NM 4939/1 (pencil inscriptions are mine; my identification label is on the opposite side); 16, S. scincicola, holotype; 17, S. scincicola, paratype NM 4870/2; 18, S. scincicola, paratype NHM 1957-8-12-35; 19, S. scincicola, non-type specimen (renounced paratype) NM 4870/3; 20, S. monticola, holotype; 21, S. monticola, paratype NHM 1957-8-12-34; 22, S. monticola, non-type specimen (renounced paratype) NM 4827; 23, S. monticola, specimen NM 4810/1 (pencil inscription “/1” is mine; my identification label is on the opposite side); 24, S. gerrhosauri, paratype NHM 1957-8- 12-36; 25, S. mabuyana, paratype NM 26422; 26, S. mabuyana, paratype NM 26423; 27, Microtrombicula (Microtrombicula) zumpti, specimen NM 5871/1 (pencil inscriptions are mine; my identification label is on the opposite side); 28, Neotrombicula (Anamasticula) rhodesiana, holotype.

FIGURE 10. Schoengastia scincicola Lawrence, 1949, holotype (A), paratype NM 4870/2 (B, D), paratype NHM 1957-8-12- 35 (C). A–C, dorsal aspect of idiosoma; D, scutum. Scale bars: 50 µm.

FIGURE 11. Schoengastia scincicola Lawrence, 1949, holotype (C, E–G), paratype NM 4870/2 (A, B, D, J–L), specimen NM 4870/3 (H, I). A, dorsal aspect of idiosoma; B, arrangement of ventral idiosomal setae; C, scutum and eyes (setules of sensillum invisible); D, sensillum; E, dorsal idiosomal seta; F, preanal idiosomal seta; G, cheliceral blades and galeal (deutorostral) seta; H, ventral aspect of gnathosoma (gnathocoxa split, cheliceral blades missing, galeal seta invisible, terminal seta on palpal tarsus broken); I, dorsal aspect of gnathosoma; J, leg I, trochanter–tarsus; K, leg II, trochanter–tarsus; L, leg III, trochanter–tarsus. Abbreviations as in Fig. 9. Scale bars: 100 µm (A, B), 50 µm (C, D), 20 µm (E, F), 20 µm (G–I), 50 µm (J–L).

FIGURE 16. Schoengastia mabuyana Lawrence, 1949, paratype NM 26422. A, dorsal aspect of idiosoma; B, arrangement of ventral idiosomal setae; C, dorsal idiosomal seta; D, humeral seta; E, preanal idiosomal seta; F scutum and eyes; G, leg I, trochanter–tarsus (microtibiala and microgenuala invisible); H, leg II, trochanter–tarsus; I, leg III, trochanter–tarsus (tarsus broken). Abbreviations as in Fig. 9. Scale bars: 100 µm (A, B), 20 µm (C–E), 50 µm (F), 50 µm (G–I).

FIGURE 17. Microtrombicula (Microtrombicula) zumpti Vercammen-Grandjean, 1965, specimens NM 5871/2 (A, B) and 5871/1 (C–Q). A, dorsal aspect of idiosoma; B, arrangement of ventral idiosomal setae; C, scutum (eyes invisible); D, humeral seta; E, dorsal idiosomal seta; F, preanal seta; G, anterior sternal seta; H, posterior sternal seta; I, coxal seta I; J, K, coxal setae II; L, coxal seta III; M, dorsal aspect of gnathosoma; N, ventral aspect of gnathosoma; O, leg I, trochanter–tarsus; P, leg II, trochanter–tarsus; Q, leg III, trochanter–tarsus.Abbreviations as in Fig. 9. Scale bars: 100 µm (A, B), 50 µm (C), 20 µm (D–L), 20 µm (M, N), 50 µm (O–Q).

FIGURE 18. Neotrombicula (Anamasticula) rhodesiana (Lawrence, 1949), holotype. A, dorsal aspect of idiosoma; B, arrangement of ventral idiosomal setae; C, dorsal idiosomal seta; D, preanal seta; E, scutum and eyes. Abbreviations as in Fig. 2. Scale bars: 100 µm (A, B), 20 µm (C, D), 50 µm (E).