Taxonomical, ecological and zoogeographical studies on anisitsiellid water mites (Acari: Hydrachnidia: Anisitsiellidae Koenike, 1910) from Madagascar
Author
Goldschmidt, Tom
text
Zootaxa
2008
2008-12-05
1954
1
1
120
https://biotaxa.org/Zootaxa/article/view/zootaxa.1954.1.1
journal article
10.11646/zootaxa.1954.1.1
11755334
5240917
Nilotonia
(
Telotaolana
)
hodivaventy
sp. nov.
(
Figs 56–70
,
Table 4
)
Type series:
Holotype
male
,
MD 71
a, Andohahela (Tulear), Isaka, spring area south pass RIP 118 (km 36),
700 m
asl
, 16.0–18.4 °C, 55–60 µS/cm,
10.09.2001
, mounted;
paratype
, same locality and date, 0/1/0 mounted.
Habitat:
Spring at
700 m
asl.
Distribution:
Madagascar
(Southern mountain region).
Derivatio nominis:
Hodi
(Malagasy) — crust,
vaventy
(Malagasy) — thick, referring to the heavy dorsal and ventral armour characterising the species.
Diagnosis:
Idiosoma small, oval; dorsal plates approximate in both sexes, Dgl-2 to -4 fused with anterior plates in males; integument coarsely lined; sexual-dimorphism in sclerotization of venter: Male with unified ventral shield, female with very large secondary sclerotization still separated between post-genital sclerite and Cx-IV; Cx-II/III medially fused in male; genital field oval pear-shaped, acetabula elongated-oval, touching each other; legs strong, relatively compact, leg-IV bearing several long, heavy setae; claws on leg-I to -III with small ventral clawlet in males, without in females, in both sexes with very tiny dorsal clawlets; leg-IV with relatively long sub-terminal seta in males, shorter in females; capitulum short, compact, rostrum short, pointed; palp compact.
Description, male
(n = 1): Idiosoma oval, pear-shaped (
Fig. 56
); dorsum mainly covered by three large, pale greyish-purple plates, nearly touching each other; posterior plate rounded, anteriorly pointed (L/W 363/ 324), including (far laterally) Dgl-5, -6 and Lgl-4, anterior plates oblique elongated-rhombic (L/W 216/113), bearing post-ocular setae, fused with Dgl-2 to -4; eyes small, oval, separated on both sides, lying free under the integument (
Fig. 57
); Dgl-1, pre-ocular setae and three platelets (central elongated, shown in
Fig. 57
) frontally between dorsum and venter; soft integument between dorsal plates and ventral shield coarsely lined; Lgl- 1, -2 and lyrifissures in soft integument between dorsum and venter, Lgl-3 fused with ventral shield; Cx-I medially long, very closely approached, caudally fused with antero-medial corners of Cx-III and caudal margin of Cx-II; medial margins of Cx-III nearly touching each other; Cxgl-2 between Cx-II and Cx-III, Cxgl-4 at anterior margin of Cx-III (
Fig. 56
); medial margin of Cx-IV fused with ventral shield, not visible, forming very narrow genital bay, caudal margin with hook-shaped protrusion, latero-caudally oblique; Vgl-3 close to latero-caudal margin of Cx-IV; pre- and post-genital sclerites completely fused with ventral shield; Vgl-2 and -4 on large platelets, directly caudal to ventral shield (partly under soft integument) (
Fig. 56
); genital field oval pear-shaped, anteriorly tapering, anteriorly and posteriorly smoothly rounded; acetabula mid-sized, elongated-oval, touching each other, Ac1 and Ac3 slightly distant from anterior and posterior margins of genital flaps; setae of Vgl-1 posterior medio-caudal margin of Cx-IV (
Fig. 56
); excretory pore without sclerotization (
Fig. 56
); genital skeleton compact, brachia distalia oblique, brachia proximalia strong, broad, oriented proximally (
Fig. 58
); legs strong, compact, bearing many large and heavy setae; claws on leg-I to -III slender with small ventral and very tiny dorsal clawlet, leg-II-5 and -6 ventrally and distally with many tiny hair-like setae (
Fig. 59
), leg-IV-3 to -5 short, compact, mainly distally with many heavy setae, leg-IV-6 distally tapering, subterminal seta relatively long (
Figs 60, 61
); capitulum compact with short, pointed rostrum (
Fig. 62
), palps compact, P1 with one dorsal seta, P2 short, ventro-lateral seta on little hump, five dorsal setae, P3 with one lateral and three dorsal setae, P4 compact, distally relatively high, ventral setae on flat protrusions, P5 compact (
Figs 62, 63
).
FIGURES 56–63.
Nilotonia
(
Telotaolana
)
hodivaventy
subgen. et sp. nov.
, male holotype (MD 71a): 56, idiosoma, ventral view; 57, idiosoma, dorsal view; 58, genital skeleton, anterior view; 59, leg-II; 60, leg-IV (sub-terminal seta on leg- IV-6 broken); 61, leg-IV-6, posterior view; 62, capitulum with left palp and chelicera, lateral view; 63, right palp, medial view. Scale bars = 100 µm.
FIGURES 64–70.
Nilotonia
(
Telotaolana
)
hodivaventy
subgen. et sp. nov.
, female paratype (MD 71a): 64, idiosoma, ventral view; 65, idiosoma, dorsal view; 66, leg-II; 67, leg-IV-2 to -6; 68, capitulum with left palp, lateral view; 69, right palp, medial view; 70, left chelicera, lateral view. Scale bars = 100 µm.
Female
(n = 1): Secondary sclerotization of idiosoma generally weaker than in male (
Fig. 64
); dorsal plates not fused with glandularia, posterior dorsal plate more oval (L/W 441/348); Dgl-2 to -6 and Lgl-4 on mid-sized platelets, closely approached to dorsal plates, two pairs of small platelets anterior Dgl-3, lateral Dgl-2 (
Fig. 65
); general shape of coxal field and genital field as in male; Cx-IV more elongated, Cx-III/IV as well as post-genital plate with extended secondary sclerotization, not fused to ventral shield, integument between coxae, genital field, pre- and post-genital plate granular, not lined (
Fig. 64
); medial margin of Cx-IV concave, Cx-IV mainly caudally and laterally extended by secondary sclerotization (lateral extension reaching far towards anterior); pre-genital sclerite broad triangular, post-genital sclerite very extended, on one side including seta of Vgl-1; Vgl-2,-4 and Lgl-3 on irregular, mid-sized platelets, one pair of mid-sized (very different size between left and right) postero-ventral platelets lateral to post-genital plate (
Fig. 64
); legs as in males, less compact (
Figs 66, 67
); gnathosoma as in males, less compact (
Figs 68-70
).
Remarks:
The two species
Nilotonia
(
Telotaolana
)
ankaratra
and
Nilotonia
(
Telotaolana
)
hodivaventy
display a striking sexual dimorphism in the degree of secondary sclerotization. Such a degree of dimorphism has not been described in other species of
Nilotonia
yet, but a weaker sclerotization in the female is also found in
Nilotonia
(
Telotaolana
)
longipalpis
sp. nov.
(see below) and in
Nilotonia violacea
.
Nilotonia
(
Telotaolana
)
ankaratra
differs from
N.
(
Telotaolana
)
hodivaventy
in a weaker secondary sclerotization, including less glandularia and leg-IV bearing heavier setae in denser rows. A similarly developed male ventral shield is found in
Nilotonia
(
s. str
.)
cooki
Panesar, 2004
; however, the latter is differentiated from the new species from
Madagascar
in the following characters: Cxgl-4 near suture between Cx-III and Cx-IV, dorsum without extended secondary sclerotization, leg-III and -IV with swimming hairs.