Riedlinia (Trombigastia) cadei ( Vercammen-Grandjean and Brennan, 1957 )

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 : 15-17

Riedlinia (Trombigastia) cadei ( Vercammen-Grandjean and Brennan, 1957)

( Figs. 5C , 7 )

Trombigastia cadei Vercammen-Grandjean and Brennan, 1957: 487 , figs. 5–6; Stekolnikov 2018: 118 .

Trombigastia (Trombigastia) cadei : Vercammen-Grandjean & Fain 1958: 26, pls. 1–2; Zumpt 1961: 143.

Riedlinia (Trombigastia) cadei : Vercammen-Grandjean 1964: 314; 1965b: 130.

Diagnosis. SIF = 7B-N-3-3111.0000; fCx = 1.1.1; fSt = 2.2; fPp = B/B/BBB; PL> AL ≥ AM; fD = 2H-6-6-6+(9–14); DS = 29–34; V = 39–42; NDV = 68–76 (in type series, fD = 2H-8-6-6-8-8-6-2; DS = 46; V = 42; NDV = 88); scutum nearly rectangular, its posterior margin straight, with cuticular striations; ALs inserted in projected anterolateral corners; sensillary bases situated anterior to level of PLs by 11–14 µm; sensilla barbed, slightly expanded, but not thicker than other scutal setae; Ip = 819–848 (785 according to original description). Standard measurements are given in Table 4 .

Distribution and hosts. This species was described from Ngong, southern Kenya, ex Miniopterus sp. ( Chiroptera : Miniopteridae ). Here I report it from South Africa and ex Rhinolophus clivosus Cretzschmar ( Chiroptera : Rhinolophidae ) for the first time.

Material examined. Three specimens, NM 6544/1–3, L = 856, Maritzburg , Natal (Pietermaritzburg, KwaZulu-Natal Prov.), South Africa, ex R. clivosus , August 1956, collector Lawrence, prepared by Vercammen-Grandjean ( Fig. 1 , 14 ) .

Remarks. The examined specimens differ from the original description in the presence of six setae in 1 st posthumeral row vs. eight, lesser DS (29–34 vs. 46) and NDV (68–76 vs. 88). Taxonomic significance of these differences is unclear; examination of a new material is required to establish if the South African R. (T.) cadei deserves the status of species or subspecies. Somewhat shorter PL (54–59 vs. 64), H (50–54 vs. 64), and D max (47–49 vs. 58) in the examined specimens fit the usual range of the intraspecific variation in chiggers. Some setae of the palpal tarsus look nude in the examined specimens vs. well-branched in the figure from the original description, but this could be caused by a suboptimal quality of the slides from NM.

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 5. Herpetacarus (Abonnencia) longispinus (Radford, 1948), holotype (A), Ascoschoengastia rhabdomyia Lawrence, 1951, specimen NM 5387, left on the slide (B), Riedlinia (Trombigastia) cadei (Vercammen-Grandjean and Brennan, 1957), specimen NM 6544/3 (C). Dorsal aspect of idiosoma. Scale bars: 50 µm.

FIGURE 7. Riedlinia (Trombigastia) cadei (Vercammen-Grandjean and Brennan, 1957), specimens NM 6544/1 (A, B), 6544/2 (D–K), 6544/3 (C). A, dorsal aspect of idiosoma; B, arrangement of ventral idiosomal setae; C, scutum (with only one broken sensillum) and eyes; D, dorsal idiosomal seta; E, preanal idiosomal seta; F, ventral aspect of gnathosoma; G, dorsal aspect of gnathosoma (dorsal palpal tibial seta invisible); H, palp, dorsal aspect; I, leg I, trochanter–tarsus; J, leg II, trochanter–tarsus; K, leg III, trochanter–tarsus. Abbreviations: S, sensillum; other abbreviations as in Fig. 3. Scale bars: 100 µm (A, B), 50 µm (C), 20 µm (D, E), 20 µm (F–H), 50 µm (I–K).

FIGURE 14. Schoengastia monticola Lawrence, 1949, specimens 4810/1 (A, B) and 4810/3 (C–L). A, dorsal aspect of idiosoma; B, arrangement of ventral idiosomal setae; C, humeral seta; D, preanal idiosomal seta; E, dorsal idiosomal seta; F, sensillum; G, scutum and eyes H, dorsal aspect of gnathosoma; I, ventral 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), 20 µm (C–E), 50 µm (F, G), 20 µm (H, I), 50 µm (J–L).