A revision of the chigger genus Afrotrombicula (Acariformes: Trombiculidae)
Author
Stekolnikov, Alexandr A.
text
Zootaxa
2023
2023-07-31
5323
1
27
55
http://dx.doi.org/10.11646/zootaxa.5323.1.2
journal article
10.11646/zootaxa.5323.1.2
1175-5326
8203863
69FB16D4-9691-4D4D-9DEC-704BA325E07D
Afrotrombicula
(
Afrotrombicula
)
claviglia
(
Radford, 1948
)
,
comb. nov.
(
Figs. 1–4
)
Trombicula claviglia
Radford, 1948: 213
, figs 1–2;
Audy & Vercammen-Grandjean 1961: 132
;
Zumpt 1961: 138
.
Trombicula
(
Trombicula
)
claviglia
:
Wharton & Fuller 1952: 64
.
Neotrombicula
(
Neotrombicula
)
claviglia
:
Vercammen-Grandjean 1965: 70
.
Neotrombicula claviglia
:
Stekolnikov 2018: 180
.
Diagnosis.
SIF = 7BS-B-3-3111.1000; fPp = B/B/NNB; PL> AM> AL; fD = 2H-6-8-8-8-8-2; DS = 42; V = 36;
NDV = 78; palpal femur and genu with puncta; scutum nearly pentagonal, much wider than long, with dense small puncta; posterior scutal margin evenly arquate; f
1
at level of S
1
; f
2
behind S
2
; Ip = 880. Standard measurements are in
Table 1
.
TABLE 1.
Morphometric (AW– S
2
, µm) and meristic (DS–NDV) traits of
Afrotrombicula claviglia
and
A. kenyaensis
.
|
A. claviglia
|
A. kenyaensis
|
| Holotype |
Original description* |
Range** |
| AW |
78 |
72 |
70–77 |
| PW |
90 |
90 |
86–89 |
| SB |
33 |
37 |
29–34 |
| ASB |
28 |
28 |
22–26 |
| PSB |
33 |
20 |
32–36 |
| SD |
61 |
48 |
- |
| AP |
34 |
33 |
28–31 |
| AM |
47 |
40 |
39–51 |
| AL |
38 |
50 |
33–46 |
| PL |
66 |
70 |
62–72 |
| S |
- |
64 |
58–67 |
| H |
64 |
- |
60–63 |
| D min |
38 |
35 |
47 |
| D max |
55 |
40 |
56 |
| pa |
311 |
- |
253–297 |
| pm |
266 |
- |
249–285 |
| pp |
303 |
- |
257–296 |
| Ip |
880 |
- |
817–841 |
| TaIIIL |
78 |
- |
74 |
| TaIIIW |
24 |
- |
18 |
| dmt |
29 |
- |
- |
| S1 |
22 |
- |
22–24 |
| S2 |
13 |
- |
15 |
| DS |
42 |
~ 38 |
38 |
| V |
36 |
~ 38 |
46 |
| NDV |
78 |
~ 76 |
84 |
Note. *—after
Radford (1948)
; **—after
Goff (1995)
.
Redescription (larval
holotype
).
IDIOSOMA (
Figs. 1
,
2
). Eyes 2 + 2; 42 dorsal idiosomal setae, including one pair of humeral setae, covered with well-developed barbs, 6 setae in 1
st
posthumeral row (C, excluding humeral setae), by 8 setae in next four rows plus 2 caudal setae, fD = 2H-6-8-8-8-8-2; 4 sternal setae; 36 ventral setae; NDV = 78.
GNATHOSOMA (
Fig. 3
). Cheliceral blade with tricuspid cap and 1 weakly developed dorsal tooth; cheliceral base, gnathobase, and palpal femur with dense puncta, palpal genu with few puncta; gnathobase with 1 pair of branched gnathocoxal (tritorostral) setae; galeal (deutorostral) seta thick and heavily branched; palpal claw with 3 prongs; setae on palpal femur and genu branched; dorsal and lateral setae on palpal tibia nude; ventral palpal tibial seta branched; palpal tarsus with 7 branched setae, nude subterminala (
ζ
) and basal tarsala (
ω
).
SCUTUM (
Fig. 1
). Nearly pentagonal, densely covered with small puncta, anterior scutal margin sinuous, lateral margins almost straight, posterior margin evenly arcuate; AM at level of AL, sensillary (trichobothrial) bases far anterior to level of PL; all scutal setae uniform with dorsal idiosomal setae; PL> AM> AL; flagelliform sensilla (trichobothria), with branches in distal part (number of branches cannot be counted).
LEGS (
Fig. 4
). 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 22B, tarsala (
ω
), microtarsala (
ε
) at level of tarsala, subterminala (
ζ
), parasubterminala (
z
), pretarsala (
ζ
). Leg II: coxa 1B; trochanter 1B; basifemur 2B; telofemur 4B; genu 3B, genuala; 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; tibia 6B, tibiala; tarsus 14B, mastitarsala.
Type deposition.
Holotype
in NHM (
BM
1948.2.3
);
paratype
in
USNM
(USNMENT 01751005) (
Bassini-Silva
et al.
2021
).
Radford (1948)
also declared deposition of
paratypes
in his private collection and in the collection of Dr. P.J. Du Toit (Zoological Survey Committee, Pretoria,
South Africa
).
FIGURE 1.
Afrotrombicula claviglia
(
Radford, 1948
)
,
comb. nov.
, holotype. Scutum. Abbreviations: AL, anterolateral scutal seta; AM, anteromedian scutal seta; H, humeral seta; PL, posterolateral scutal seta; S, sensillum (trichobothrium). Scale bar: 50 µm.
FIGURE 2.
Afrotrombicula claviglia
(
Radford, 1948
)
,
comb. nov.
, holotype.
A
, arrangement of dorsal idiosomal setae;
B
, arrangement of ventral idiosomal setae (anus invisible). Abbreviations: H, humeral seta; V, ventral idiosomal setae. Borders between rows of setae are showed by dotted lines.
FIGURE 3.
Afrotrombicula claviglia
(
Radford, 1948
)
,
comb. nov.
, holotype.
A
, ventral aspect of gnathosoma;
B
, dorsal aspect of gnathosoma. Abbreviations: Cb, cheliceral base; Cs, cheliceral blade; Ga, galeal (deutorostral) seta; gns, gnathocoxal (tritorostral) seta; ic, infracapitulum (gnathobase, gnathocoxa); PC, palpal claw (odontus); PF, palpal femur; PG, palpal genu; PTa, palpal tarsus; PTi, palpal tibia; S
0
, palpal tarsala (
ω
); ζ, palpal subterminala (
ζ
). Scale bars: 50 µm.
FIGURE 4.
Afrotrombicula claviglia
(
Radford, 1948
)
,
comb. nov.
, holotype.
A
, legs I, II;
B
, leg III. Abbreviations: ga, genuala
I (
σ
); gm, genuala II (
σ
); gp, genuala III (
σ
); Mt, mastitarsala (broken); PT’, pretarsala I (
ζ
); PT”, pretarsala II (
ζ
); S
1
, leg tarsala I (
ω
); S
2
, leg tarsala II (
ω
); ST, subterminala (
ζ
); ta, tibiala I (
φ
); tm, tibiala II (
φ
); tp, tibiala III (
φ
). Scale bars: 50 µm.
Distribution and host.
This species was described from
Uganda
(
Serere
), ex
Graphiurus murinus
(Desmarest)
(
Rodentia
:
Gliridae
).
Type material examined.
Holotype
(
BM
1948.2.3
) ex
Graphiurus murinus
,
Uganda
,
Serere
, Teso,
3 Oct. 1945
,
G.H.E. Hopkins.
Remarks.
This species should not be mixed with
Trombicula claviglicola
Lawrence, 1949
(
Stekolnikov 2018
).