A STUDY ON THE GENUS Sphaeridium FABRICIUS, 1775 (COLEOPTERA: HYDROPHILIDAE) IN KÜTAHYA PROVINCE, WESTERN TURKEY

Turkiye batisinda Kutahya’da, Haziran 2010’dan Mayis 2011’e kadar, 14 lokalitede ve farkli yuksekliklerde (469m-1810m) yemli cukur tuzaklar kullanilarak koprofil Hydrophilidae ornekleri toplanmistir. Calisma sonucunda toplam 5 ture ait 668 ornek tespit edilmistir. Toplanan orneklerin Sphaeridium bipustulatum Fabricius, 1781, S. lunatum Fabricius, 1792, S. marginatum Fabricius, 1787, S. scarabaeoides (Linnaeus, 1758) ve S. substriatum Faldermann, 1838 turlerine ait olduklari belirlenmistir. S. lunatum Turkiye’den ilk kez kayit edilmistir. Toplanan boceklerin %80,69'unu olusturan S. bipustulatum ve S. marginatum en baskin turler olarak belirlenmistir. Aralik ayindan Nisan ayina kadar yogun ornek elde edilmis olmasi, calisma alani icerisindeki Sphaeridium populasyonlarinin kis ve ilkbahar doneminde en yuksek birey sayilarina ulastigini gostermektedir.


Introduction
Members of the family Hydrophilidae are mostly represented with an aquatic lifestyle but a third of all known species of the family are terrestrial scavengers. The colonization of terrestrial habitats occurred secondarily multiple times and terrestrial taxa are therefore found in five of six existing subfamilies although the vast majority of terrestrial taxa belong to a single subfamily Sphaeridiinae (Short & Fikáček 2013) which currently contains nearly 1,000 described species (Hansen 1999, Short & Hebauer 2006, Short & Fikáček 2011. Sphaeridiinae members are terrestrial organisms living in various kinds of decaying organic matter. In northern temperate zones, most of the species within this subfamily are coprophagous and colonize animal droppings in early stages of decomposition (Fikáček 2010). Unlike most aquatic hydrophilids whose life cycles are known, several terrestrial species apparently have two generations per year (Hansen 1987).
The community structures and seasonal dynamics of coprophagous hydrophilid beetles have been reported so far for beetles from various regions of the world (Hanski 1980a

Study Area
Kütahya province is situated between 38º70'-39º80'N and 29º00'-30º30'E in the interior western Anatolian part of Aegean Region of Turkey. The geographical layout of the study area and the sampled localities are given in Fig.1.
Locality 1: The sampled area is located along a river, thus shows characteristics of a riparian habitat. The traps in this locality were set up in a plantation of Pinus brutia Ten, Fraxinus sp., Onopordum sp., Verbascum sp., Mentha sp., Juncus sp. and Epilobium sp.

Sampling Method
Samplings were performed from June 2010 to May 2011 in 14 different localities within the study area with altitudes ranging from 469m to 1810m. Altitudes and geographic coordinates of the sampling localities are given in Table 1. A single sampling station was chosen for each locality and samplings were performed in a manner to keep an average of 100m altitude increase from one to another locality ( Table 1). All specimens were collected by using baited pitfall traps with 1,000gr of fresh cow dung. The trap consisted of a plastic bucket (20cm in height and 25cm in diameter) buried in the soil with its rim at ground level. The upper part of the trap was filled with fresh dung placed on a wire mesh. Water, liquid detergent and 4% formaldehyde was used as the preserving fluid. Traps were placed in the field for 3 days (72 hours) each month from June 2010 to May 2011.   Hansen (1987) was used to identify the species. The taxonomic characters including size of the beetle, posterior margin of pronotum, apical elytral spots, subhumeral spots, colour of the pronotum and meso-and metafemora were used to identify the species. Aedeagus were dissected out under a stereo microscope (Zeiss Stemi 2000) and kept in 10% KOH solution for 1-2h. Voucher specimens are deposited in entomology museum of the Biology Department at Dumlupınar University.
The following equation (1) was used as a measure of dominance (D) which, according to Tischler (1977), describes the relative abundance of a species within a community.

= * 100
(1) where "b" represents number of individuals of a particular species and "a" represents number of total individuals.
The Dominance scale (given below) according to Engelmann (1978) was used.
The evaluation of the collected material showed that a total of 668 specimens belonging to five species were sampled. The species were identified as Sphaeridium bipustulatum, S. lunatum, S. marginatum, S. scarabaeoides and S. substriatum. Among them which S. lunatum (Fig. 2) is recorded from Turkey for the first time.
The details of the material collected were given below. Each species determined during the study was given with the sampled localities and sampling numbers. The distributional ranges of each species in the Palaearctic Region were also given in addition to their Turkey distributions.

Discussion
The field investigation on Sphaeridium in Kütahya province was conducted for the first time and five species were recorded in the study area. All species are new records for fauna of Kütahya and S. lunatum is new record for Turkish fauna. Dominance status of each species was described on the basis of relative abundance following Engelmann's (1978) dominance scale ( Table 2). According to the analysis, two species were referred as subdominant (S. scarabaeoides, S. lunatum), one species as dominant (S. substriatum) and two species as eudominant (S. bipustulatum, S. marginatum) status.
In Europe, while S. bipustulatum is the rarest species, S. lunatum and S. scarabaeoides are dominant species (Hanski 1980b). In this study, it was determined that S. bipustulatum species was eudominant (Table 2). In contrast to their status in Europe our results showed that S. lunatum and S. scarabaeoides species were found to be subdominant. According to Hanski (1980b), the spatial patterns shown by S. lunatum and S. scarabaeoides were the same. The researchers determined that the numbers of both species were positively correlated both between fields within a single locality and between different ages of the same dropping. Our results also showed the same positive correlation between these two species. Similarly, S. bipustulatum was eudominant in Spain according to Romero-Alkaraz et al. 1997, followed by S. marginatum and S. scarabaeoides. The order of dominance of these species is in a harmony with our study.
Seasonal changes in the community compositions were given by the differences in phenology of the species. The numbers of sampled beetles increased from the beginning of December until the end of April. The highest numbers of beetles were observed during winter and spring and a drastic decline was determined by July (Fig.  3). Hanski (1980b) determined that S. scarabaeoides was not trapped in June and August. When the recorded species were considered according to their highest sampling numbers with respect to sampling months, S. bipustulatum showed its peak in March, S. marginatum and S. scarabaeoides in February, S. substriatum and S. lunatum in December (Fig. 3). So, there is no activity in July and August. Alkaraz et al. 1997 determined that S. scarabaeoides did not show any activity from July to November, S. bipustulatum from November to May and S. marginatum in January in Spain. In the present study, localities numbered from 1 to 5 (up to about 900 meters) had the higher number of individuals in total (Fig. 4). Rahbek (1995) indicated that species richness declines at high altitudes because of temperature and productivity decrease along with increasing elevation.