A NEW GENUS OF THE WATER MITE FAMILY PIERSIGIIDAE FROM AUSTRALIA (ACARI HYDRACHIDIA)

4 Pages·1998·1.1 MB·English

by  Harry Smit

Records of the Western Australian Museum 19: 107-110 (1998).
A new genus of the water mite family Piersigiidae from Australia
(Acari: Hydrachnidia)
Harry Smit
Emmastraat 43-a, 1814 DM Alkmaar, The Netherlands
Abstract - A new genus from the water mite subfamily Piersigiinae and its
sole new species, AustrapiersiRia montana, are described from Victoria,
Australia. It is the first record of this subfamily for the southern hemisphere.
INTRODUCTION Genus Atistrapiersigia gen. nov.
The water mite family Piersigiidae contains tw'o
Type Species
distinct subfamilies, the Piersigiinae and the
Austrapiersigia monimia sp. nov.
Stygolimnocharinae. The Piersigiinae, with the only
genus PiersiRia Protz, have been collected only in
Diagnosis
the Holarctic. Most of the four described species of
Characters of the subfamily Piersigiinae. Dorsum
this subfamily inhabit temporary water bodies or
with two pairs of large plates medially and one
semi-aquatic habitats (Imamura and Mitchell 1967;
large plate posteriorly, none of them encompassing
Van Maanen et. al. 1997). However, because of its
glandularia.
reduced lateral eyes, Piersigia criista Mitchell might
be an interstitial species (Cook 1974). The
Stygolimnocharinae, with the genera Description
Stygolitnnocliares Cook and Parawandesia E. Lateral eyes in capsules, incorporated into an eye
Angelier, are known from India, Australia and plate composed of tw'o pairs of glandularia
Europe. The three know'n species of these genera platelets and the pre- and postocularia platelets,
live in interstitial habitats (Cook 1967, 1986; loosely joiiied by sderotized bridges. A clear area
in the anterior part of the largest eye platelet might
Gerecke and Cook 1995).
be a median eye. Glandularia sclerites partially
Utilising the Karaman-Chappuis method (see
Schwoerbel 1979), an interstitial water mite surrounding the large glandularia. Dorsum
belonging to the subfamily Piersigiinae was medially w'ith two pairs of large plates, and
posteriorly with one large plate. Capitulum with a
collected in Victoria. This is not only the first
large circular mouth opening containing a frilled,
record of this subfamily for Australia, but also for
w'heel-like membrane. Coxal plates in four groups.
the southern hemisphere. Tlie species belongs to a
Acetabula numerous, in four groups, surrounded
new' genus, and is described below.
by sderotized rings. Acetabula shortly stalked.
Excretory pore on a sclerite. PHI expanded
MATERIAL AND METHODS laterally.
The material has been collected by the author.
Remarks
The holotype has been deposited in the Museum of
The new genus shares many characters with the
Victoria, Melbourne.
genus Piersigia, but differs noticeably in the
Measurements of palp and leg segments are
arrangement of plates on the dorsum and the
dorsal lengths. All measurements are in pm. The
shape of Pill. All knowm Piersigia species have
body length is measured dorsally from the
relatively large, rectangular lateroglandularia
unmounted specimen. The following abbreviations
platelets which are lacking in Atistrapiersigia, and
have been used: PI-PV palp segments 1-5; I-leg-5
have the other glandularia platelets more or less
fifth segment of first leg.
cre.scent shaped (as in Austrapiersigia). The dorsal
plates of Piersigia are small, elongate and
irregularly shaped, and those of Austrapiersiga
SYSTEMATICS
large with rounded corners.
Family Piersigiidae Oudemans
Etymology
Subfamily Piersigiinae Oudemans The name of the new genus refers to its southern
H. Smit
108
Figures 1, 2 Aiiftrapicrfij^ia montaiia sp. niiv., holotype 9: 1, dorsal view; 2, ventral view. Scale line 200 pm.
A new genus of Piersigiidae
109
Figures 3-5 Auslrapiersigia montam sp. nov., holotype $: 3, lateral view of PlI-PV; A, dorsal view of PII-PIII; 5, I-
leg-5-6. Scale lines 50 pm.
110
H. Smit
occurrence and the similarity with the genus Etymology
Piersigia.
The name refers to its occurrence in the
mountains of the Dividing Range.
Austrapiersigia montima sp. nov.
Figures 1-5 ACKNOWLEDGEMENTS
Material Examined 1 am indebted to the Department of Natural
Resources and Environment (Melbourne) for their
Holotypc permission to collect water mites in the national
9, interstitial of unnamed creek. The Tong Plain parks of Victoria and to Dr M.S. Harv'cy for his
(± 1300 m above sea level), Mt Buffalo National comment on a first draft of this paper.
Park, Victoria, Australia, 10 October 1997.
Diagnosis REFERENCES
As for genus. Cook, D.R. (1967). Water mites from India. Memoirs of
the American Entomological Institute 9: 1-411.
Description Cook, D.R. (1974). Water mite genera and subgenera.
Memoirs of the Entomological Institute 21: 1-860.
Female Cook, D.R. (1986). Water mites from Australia. Memoirs
Body 1319 long and 980 wide. Integument soft, of the American Entomological Institute 40: 1-568.
papillate, body colour orange. Posterior part of eye Gerecke, R. and Cook, D.R. (1995). Morphology,
plate rounded, 242 long. This large plate with a systematic position and zoogeography of
clear area which might be a median eye. Dorsum Paraivandesia chappuisi E. Angelier, 1951 (Acari,
medially with two pairs of large plates (Figure 1), Actinedida, Piersigiidae). Zoologischer Anzeiger 234
125-131.
the anterior 281 in width, the posterior 340-369 in
width. Posterior plate of dorsum 582 in width. Imamura, T. and R. .Mitchell (1967). The ecology and life
history of the water mite, Piersigia limnophila Protz.
Coxal plates in four group.s, covered with many
Annotationes Zoologicae japonensis 40; 37-44.
fine setae. Genital field 218 in length. Acetabula
Schwoerbel, J. (1979). Methoden der Hydrohiologie.
shortly stalked, located in four groups (Figure 2),
Siijhoasserbiologie. Second edition. G. Fisher,
the anterior groups more elongated compared to
Stuttgart.
posterior groups. Each group has 21-22 acetabula.
Van Maanen, B., Tempelman, D. and Smit, H. (1997).
Lengths of PI-PV: 32, 94, 98, 70, 36. PHI with a
Piersigia koenikei new for the Dutch fauna and new
group of setae at anteroventral comer (Figure 3), Dutch records of Piersigia intermedia and Vietsia
PHI greatly expanded laterally (Figure 4). Lengths scutata (Acari: llydrachnellae). Entomologische
of l-leg-4-6: 115, 156, 173. Lengths of IV-leg—4-6; Berichten, Amsterdam 57; 113-118.
165, 194, 223. Legs with numerous stout, serrated
setae (Figure 5); swimming setae absent, claws
Manuscript received 1 December 1997; accepted 76 March
simple. 1998.