Data on the distribution of Hystrichopsylla orientalis fleas (Siphonaptera) in Lithuania

INTRODUCTION

Fleas (Siphonaptera) are common ectoparasites of mammals and birds in different habitats throughout the world. More than 2500 species within 18 families of fleas are known (Krasnov, 2008). Only five flea families occur on birds and all other species parasitize mammals (Whiting et al., 2008).

The genus Hystrichopsylla Taschenberg, 1880 is composed of more than 30 species/subspecies. Fleas of this genus are the  largest fleas in the world, with the body length that can reach up to 10 mm (Holland, 1957; Rosicky, 1957; Brinck-Lindroth, Smit, 2007). Fleas of Hystrichopsylla species are more commonly found in nests, but are also found in small amounts on the body of a host (Stanko et al., 2002; Brinck-Lindroth, Smit, 2007; Krasnov, 2008). They are primarily found on insectivores and rodents and occasionally on birds (Brinck-Lindroth, Smit, 2007; Whitaker, 2007). Currently, one member of the genus Hys­trichopsylla – Hystrichopsylla talpae Curtis, 1826 (Pakalniškis, Žygutienė, 2004) is on the  list of Lithuanian flea fauna. Therefore, the aim of this study was to present data on the distribution of Hystrichopsylla fleas collected from different small animals in Lithuania.

MATERIALS AND METHODS

Fleas were selected from samples collected from different small animals between 2011 and 2017, and stored in 70% ethanol at –20°C until further investigation. Identification of fleas before species and sex was done with a stereomicroscope with the aid of keys (Rosicky, 1957; Brinck-Lindroth, Smit, 2007).

Flea samples were fixed on permanent microscopic preparations in Canada balsam (Brinck-Lindroth, Smit, 2007). The preparations are stored at the  Department of Biology, Vytautas Magnus University (Kaunas, Lithuania). Flea samples were also documented using digital camera.

RESULTS AND DISCUSSION

In the  present study, 96 Hystrichopsylla orien­talis Smit, 1956 fleas were collected from nine (Apodemus flavicollis, Apodemus agrarius, Mi­cromys minutus, Myodes glareolus, Microtus oeconomus, Microtus arvalis, Sorex araneus, Neomys fodiens, and Glis glis) mammalian species in ten localities of Lithuania (Table). In previous studies, another flea species of the genus Hystrichopsylla  –  Hystrichopsylla talpae Curtis, 1826 – was detected on A. flavicollis, A. agrari­us, Mus musculus, Microtus agrestis, M. arvalis, and M. glareolus in Lithuania (Likevičienė, 1957; Kadytė, 1964; Jeziorskienė, 1974; Lipatova, Paulauskas, 2010). Moles (Talpa europaea) are primary hosts of Hystrichopsylla fleas. However, they are also found on other small mammals such as voles (Cricetidae), mice (Muridae), and shrews (Soricidae) (Smit, 1957; Brinck-Lindroth, Smit, 2007; Baláž, Zigová, 2020). Hystrichopsylla fleas are found very rarely in the nests of dormice (Libois, 1979; Kirillova et al., 2006). Also, sometimes Hystrichopsylla fleas can parasitize weasels (Mustela), baadgers (Meles), foxes (Vulpes vulpes), rabbits (Oryctolagus cuniculus), birch mice (Sicista betulina), rats (Rattus norveg­icus), birds (Anthus trivialis), and even the nests of bumblebees (Bombus) (Skuratowicz, 1967).

Fleas of H.  orientalis species are morphologically very similar to H.  talpae species. Their main difference is the  number of stout outer setae on hind tibia. H. orientalis flea species has three setae on the penultimate notch of the posterior margin, while H. talpae has only two setae (Figs. 1–2) (Brinck-Lindroth, Smit, 2007). All analyzed Hystrichopsylla fleas had clear three setae on hind tibia (Fig. 3). Females of both species have two spermathecae. However, H. orientalis flea species has base of ductus bursae with dark sclerities, while H. talpae has base of ductus bursae without sclerotisation (Fig. 4–5) (Brinck-Lindroth, Smit, 2007). A total of 53 females of Hystrichopsylla species fleas were collected. All of them had sclerotized base of ductus bursae (Fig. 6 A-B). Males of these two species have small morphological diversity on setae of sternum IX and aedeagus. H.  orientalis flea species has well separated basal spiniform setae of sternum IX from other crowded together spiniforms, while H. talpae has rather widely and uniformly spaced spiniform setae of sternum IX (Fig. 7–8) (Brinck-Lindroth, Smit, 2007). A total of 43 males of Hystrichopsylla fleas were collected. All of them had basal spiniform setae of sternum IX separated from other spiniforms (Fig. 9 A-B).

Table. Distribution of Hystrichopsylla orientalis in small mammals in Lithuania

n – number of collected animals

Both species of fleas have similar host specificity and the same biology, but the distribution is slightly different. H.  talpae fleas are found in Poland, Latvia, Estonia, Norway, Germany, the  Netherlands, Belgium, France, Switzerland, northern Italy, northern Spain, Hungary, the Czech Republic, Slovakia, Austria, Luxembourg, the United Kingdom, Ireland, Denmark, Bulgaria, Greece, Turkey, and extend eastwards to the Krasnoyarsk region in Russia and southwards to the Altai, Tian Shan, and the Caucasus mountains (Holland, 1957; Skuratowicz, 1967; Smit, 1969; Pototski, 1990; Brinck-Lindroth, Smit, 2007; Whitaker, 2007). H. orientalis fleas are distributed in continental and eastern Europe, in southern Poland to Switzerland, in northern Italy, including Russia and Siberia in the  east (Smit, 1969; Brinck-Lindroth, Smit, 2007; Baláž, Zigová, 2020). Both species of fleas are found during late summer or autumn. This study is the first report on the presence of H. orientalis fleas in Lithuania. Fleas were collected during autumn season (37 in September, 48 in October, and eight in November).

CONCLUSIONS

The results of this study have shown that H. ori­entalis fleas are distributed in Lithuania.

ACKNOWLEDGEMENTS

The author is very grateful to Povilas Sakalauskas for photographing the  specimens of Hys­trichopsylla orientalis.

References

Indrė Lipatova

HYSTRICHOPSYLLA ORIENTALIS RŪŠIES BLUSŲ (SIPHONAPTERA) PAPLITIMAS LIETUVOJE