Philonthus spinipes Sharp, 1874

Mazur, Andrzej, Guo, Wanyue & Górz, Andrzej, 2017, Notes on distribution and ecology of Philonthus spinipes Sharp (Coleoptera: Staphylinidae) in the Polish Carpathians, Zootaxa 4358 (3), pp. 577-582 : 577-580

Philonthus spinipes Sharp

for the first time was described from East Asia ( Sharp 1874). Presently the species occurs in the whole Palaearctic region. Original distribution of this species is difficult to define because it has obviously extended its distribution range westwards ( Schillhammer 1999).

The first information about occurring this species in Europe from 1980–1985 includes localities from line Balkans—north-east Germany ( Schülke & Uhlig 1989a, 1989b). It is a flying epigeic beetle, occurring in Europe in compost and manure, and also on carrion. At the end of the 20th century it was known from almost all regions of Poland, from both lowland and mountain areas (also from buffer zones of protected areas). It is of no economic importance, effectively competing with the native Philonthus nitidus (F.) ( Schillhammer 1999). If the expansion is continued at the present rate, one may expect that during the next decade the range of invasive P. spinipes will extend to the east and west of Europe ( Pawłowski 2008).

Distribution of Ph. spinipes . The species has been recorded in Europe, Armenia, Kazakhstan, China, Korea, Japan and Taiwan ( Herman 2001; Hromádka 2012). Philonthus spinipes was reported in Armenia, Austria, Belgium, Bulgaria, Central Russia, the Czech Republic, Germany, Finland, France, Great Britain, Greece, Italy, Moldavia, Poland, Romania, Slovakia, southern Russia, Sweden, Switzerland, Ukraine and former Yugoslavia ( Burakowski et al. 2000; Löbl & Smetana 2004; Roy et al. 2011).

It was recently found also in Latvia, Iran (Cibuļskis at al. 2005, Samin et al. 2011a, 2011b).

In Asia it was found in Japan, North and South Korea, and in China, in the provinces of Beijing, Gansu, Heilongjiang, Jilin, Liaoning, Shanghai, as well as in Taiwan ( Löbl & Smetana 2004).

In Poland this species was briefly mentioned in the catalogue of beetles of Central Europe ( Lohse 1989) and next reported successively from the area of Koszalin, the Białowieża Primeval Forest and from Pińczów in the Małopolska Upland ( Borowiec 1991).

Distribution in Poland is presented on the site of the Polish Biodiversity Information Network ( Tykarski 2014).

Ecology. Philonthus spinipes is a typical coprophile, colonising various types of dead organic matter such as excrements, compost piles, carrion, accumulated plant residue. It is found most frequently in droppings on pasture ( Burakowski et al. 2000; László 2004; Pawłowski 2008). It is a predatory species, the larvae and imagines successfully hunting other small insects colonising excrements, e.g. coprophagous beetles or flies.

It is defined as an expansive species, extremely fast colonizing new, probably open habitats throughout Poland ( Szujecki 2008). In the mountains it may reach the upper tree limit ( Schülke & Uhlig 1989b; Brandstetter & Kapp 1994; László 2004). The beetles can easily reach the islands ( Rose & Möhlmann 1993).

In such a microhabitat it probably competes with native species, particularly Philonthus nitidus (FABR. 1787). This opinion was expressed in a study by H. Schillhammer (1999): “ Philonthus spinipes is a habitat competitor with P. nitidus and has gradually displaced it, with the consequence that, especially in Central Europe, P. nitidus has become very rare”.

Materials and methods

Study area. The research on biodiversity of dung beetles (Scarabaeoidea) was conducted from 2011 to 2013 in the Polish Carpathians.

Sampling method (collection of dung beetles). Insects were caught at 51 experimental sites ( Fig 1 ). Three traps were distributed at each of the localities. The traps were composed of a 20 cm high plastic container with a diameter of approx. 17 cm filled with a preservative liquid—ethylene glycol (approx. 200 ml). This element of the trap was deposited in the soil with its rim at the ground level. It was covered by a 15 mm wire mesh with approx. 800 g of fresh animal excrements placed on top. The trap was protected from rain by a lid with a diameter of approx. 25 cm placed on nails driven in the ground. Three traps at 10 m intervals were distributed at each site. The traps were emptied once every 10–12 days.

The distribution of experimental sites in the Polish part of the Carpathians is presented in Fig. 1 .

Results

At 51 experimental sites in southern Poland in 310 samples a total of 12 470 specimens of Staphylinidae were identified. In this experimental material at 11 localities 31 specimens of Ph. spinipes were recorded in 16 samples: Tatry: Tatrzański National Park—Kocioł Mułowy, 980 m, montane zone, meadow and tall herb pasture (sheep grazing), 18. VIII.2012, 2 ♂♂; Tatrzański National Park—Kasprowy Wierch (Twarda Galeria), 1776 m, alpine zone, meadow and tall herb pasture (no grazing), 5. IX.2013, 1 ♂; Pieniny: Sromowce Niżne, 584 m, montane zone, meadow and tall herb pasture of southern exposure (sheep grazing), 15. X.2012, 1 ♂; Beskid Sądecki: Gołkowce Dolne, 317 m, foothills, fresh meadow from the association Arrhenatheretum alatioris (no grazing), 5. VII.2013, 2 ♀♀, 21. IX.2011, 2 ♂♂, 14. X.2013, 1 ♂; Beskid Zachodni: Ciężkowice—Pleśna, 263 m, foothills, fresh meadow from the association Arrhenatheretum alatioris (cattle grazing), 24. VIII.2011, 1 ♂; Beskid Wschodni: Strzyżowskie—Stasiówka, 395 m, foothills, fresh meadow from the association Arrhenatheretum alatioris (cattle grazing), 5. X.2011, 1 ♂ and 2 ♀♀; Góry Słonne—Stefkowa, 406 m, foothills, fresh meadow from the association Arrhenatheretum alatioris (cattle grazing), 9. IX.2011, 1 ♂, 19. IX.2011, 1 ♂ and 2 ♀♀, 29. IX.2011, 4 ♂♂ and 4 ♀♀; Beskid Niski: Magurski National Park—Ciechań, 629 m, montane zone, meadow and tall herb pasture (no grazing), 15.V. 20113, 1 ♀, 6. VIII.2013, 1 ♀; Bieszczady: Łopienka/Buk, 592 m, montane zone, meadow and tall herb pasture of southern exposure (no grazing), 20. V.2013, 1 ♀; Buk/Cisna, 533 m, montane zone, meadow and tall herb pasture (no grazing), 10. V.2013, 2 ♀♀; Brzegi Górne, 773 m, montane zone, meadow and tall herb pasture of southern exposure (no grazing), 15. V.2013, 1 ♂.

In the above mentioned localities Philonthus spinipes was found together with 697 other representatives of Staphylinidae .

The dominance index (D) for Ph. spinipes in samples ranges from 1.08 to 33.3 at mean 8.02. The index calculated for the entire collected material was D = 0.25.

The incidence frequency index was C = 5.16.

Analysis of sex structure. The ratio of males to females is 1.067. The frequency of incidence of sexes in the months of the vegetation season is given in Fig. 2 . Males are more numerous in the period from July to October. Females were recorded more often only in May. In June no specimens of Ph. spinipes were observed, while in July only males were recorded.

Analysis of the vertical range of the species. Philonthus spinipes is found most frequently in biotopes located up to 500 m a.s.l. Its incidence frequency decreases up to 1000 m a.s.l. No beetles of this species were found at altitudes of 1000–1500 m a.s.l. In the massif of Kasprowy Wierch and in the Kocioł Mułowy, i.e. above 1700 m a.s.l. 3 males were recorded.

Analysis of habitat preferences. Beetles were caught at two types of habitats: one with animal grazing and the other with no grazing activity. At three localities: Sromowce Niżne, Stefkowa and Ciechań, in 5 samples together with specimens of Ph. spinipes the similar large rove beetle Philonthus nitidus (Fabr.) was found.

In the biotopes with grazing activity a total of 276 specimens of Staphylinidae were collected, including 20 specimens of Ph. spinipes . Among them males predominated at a 1.5:1 ratio.

In the biotopes with no grazing activity the total number of specimens of Staphyinidae was 421, including 11 specimens of Ph. spinipes . In such biotopes females predominated at a 1.75:1 ratio.

In samples, in with both large rove beetle species, Ph. spinipes was more numerous. However, the ratio of Ph. spinipes specimens to specimens of Ph. nitidus varied in samples, amounting to 1, 8, 0.75, 0.33 and 1. Thus in two samples the frequency of incidence for both species was equal, in one sample Ph. spinipes was more numerous, while in two samples Ph. nitidus was found in greater numbers.

Discussion

The route of expansion of this species in Poland is provided by many studies. In a study by J. Pawłowski (2008) potential migration routes are presented for this species from the south to the north of Europe. Philonthus spinipes was caught in Poland as early as 1982 in Koło in central Poland.

In Poland in the last 35 years (1982–2016) a total of at least 141 specimens of this species were found ( Schülke & Uhlig 1989b; Borowiec 1991, 1996; Kubisz & Melke 1994; Staniec 1996, 2010; Melke & Szafraniec 1998; Melke & Maciejewski 1999; Derunkov & Melke 2001; Komosiński 2001; Kubisz & Szafraniec 2003; Smoleński 2006; Szujecki 2008; Mądra et al. 2014). The reports on 31 specimens of Ph. spinipes at 11 localities in the Polish part of the Carpathians provide important data to the biogeography and ecology of this large rove beetle species.

The majority of data on the site and habitat of Ph. spinipes indicate that this species prefers open spaces, only occasionally it is found in forests ( Smoleński 2006; Mądra et al. 2014). Preferences towards open areas were shown in the study by the team of the authors conducting investigations on large rove species colonising pig carrion ( Mądra et al. 2014). Philonthus spinipes is a species which is found in very large numbers in non-forest biotopes. In analogous studies conducted in Belgium ( Dekeirsschieter et al. 2013) this species was not observed in forests.

This species may reach the highest parts of mountains, above the upper limit (e.g. Czerwone Wierchy in the Tatras), as indicated by literature data ( Kubisz & Melke 1994) and observations reported in this study. Although the frequency of specimens decreases with the increasing altitude in the Carpathians, low diurnal heat sums, characteristic of high mountain and alpine habitats, do not limit the presence of Ph. spinipes .

It may be stated with a considerable degree of certainty that Ph. spinipes is a species tolerating well low temperatures, as indicated by the tendency to colonise regions of Europe located increasingly farther to the north ( Silfverberg 1995, 2005).

An interesting phenomenon is connected with the competition of an alien species, such as Ph. spinipes for the European fauna, in relation to other species of large predatory rove beetles colonising excrements. This problem is stressed by H. Schillhammer (1999, 2011), who stated that competition results in a decrease in the population size of the native rove beetle species Philonthus nitidus , which in many regions of Europe is becoming an increasingly rare species.

If we assume the population size of Ph. spinipes as a measure of competition, based on the data collected in the Polish Carpathians it may be stated that farm animal grazing (resulting in larger resources of animal droppings in the environment) results in reduced numbers of coprophilous Staphylinidae , and thus competition between species, leading to an increased number of Ph. spinipes . In turn, a lack of grazing causes a much higher frequency of rove beetles in traps with animal excrements and an increased competition between species, which leads to the reduction of the Ph. spinipes population size. This problem will be analysed in detail and presented in a separate publication.

Figures

FIGURE 1. Map of Polish Carpathians with 51 locations presented in the study. White marks—locations in which coprophilous beetles were collected, black marks—locations in which Philonthus spinipes was collected

FIGURE 2. Analysis of incidence frequency of males and females of Philonthus spinipes in the months of the vegetation period