Caryospora peneireiroi n . sp . ( Apicomplexa : Eimeriidae ) in the common kestrel , Falco tinnunculus ( Falconiformes : Falconidae ) , in mainland Portugal

The common kestrel Falco tinnunculus Linnaeus, 1758, is a widespread raptor, native in Europe, Asia and Africa, and vagrant in the Americas. In the current work, 27 fecal samples were collected from common kestrels kept in the Lisbon Center for Wild Animal Recovery, located at Monsanto Forest Park, Lisbon, Portugal. Five (19%) of them were found to be passing an undescribed species of Caryospora in their feces. The oocysts of Caryospora peneireiroi n. sp. were ellipsoidal with a bilayered wall and measured 47.1 × 37.6 μm with a shape index of 1.25. No micropyle, oocyst residuum or polar granule was present. The sporocysts were subspherical, measuring 25.1 × 24.3 μm. Stieda, sub-Stieda and para-Stieda bodies were absent. The sporocyst residuum was composed of many homogenous globules scattered throughout the periphery of the sporocyst. This is the fourth caryosporan species reported from F. tinnunculus.


Introduction
The common kestrel Falco tinnunculus Linnaeus, 1758, is a raptor observed in several environments, easily recognizable through its ability to hover while searching for its prey.In Portugal, this species was one of the most abundant in the 1940s; however, it suffered a sharp decline over the subsequent decades.Nowadays, although the population trend appears to be still decreasing, it is recognized that the population size is still extremely large (PALMA, 1985;Birdlife International, 2015).
Genus Caryospora Leger, 1904, is occasionally reported in raptors and reptiles, which act as its definitive hosts, and in rodents, which act as its intermediate hosts (UPTON et al., 1990;BERTO et al., 2014).Caryospora is the third largest genus in the family Eimeriidae.Caryospora spp.have now been reported worldwide, especially in raptors kept in captivity (UPTON et al., 1992;PAPAZAHARIADOU et al., 2001;MCALLISTER et al., 2013a, b).However, little is known about the distribution and importance of species of the genus Caryospora in free-living birds (YANG et al., 2014).The current work describes a new species of Caryospora from the common kestrels F. tinnunculus that were being kept for rehabilitation and reintroduction into the wild at the Lisbon Center for Wild Animal Recovery (Centro de Recuperação de Animais Silvestres de Lisboa, LxCRAS), Monsanto Forest Park, Lisbon, Portugal.

Materials and Methods
Twenty-seven fecal samples were collected from common kestrels that were being kept in individual cages on the premises of the Lisbon Center for Wild Animal Recovery (LxCRAS), located in Monsanto Forest Park, Lisbon, Portugal.The samples were collected immediately after defecation and were placed in plastic vials containing 2.5% potassium dichromate (K 2 Cr 2 O 7 ) solution at 1:6 (v/v).In the laboratory, the samples were incubated at room temperature for 10 days or until day three when around 70% of the oocysts had sporulated.The oocysts were recovered by means of flotation in Sheather's sugar solution (specific gravity: 1.20).Morphological observations, line drawings, photomicrographs and measurements were made using an Olympus BX40 microscope equipped with a digital camera (Olympus DP10).The line drawings were edited using two software applications from CorelDRAW  (Corel Draw Graphics Suite, Version 11.0, Corel Corporation, Canada), specifically Corel DRAW and Corel PHOTO-PAINT.All measurements were made in micrometers and are given as the range followed by the mean in parentheses.The descriptions of oocysts and sporocysts followed the guidelines of Duszynski & Wilber (1997) and Berto et al. (2014), as follows: oocyst (O) length (L) and width (W) and their ranges and ratios (L/W); micropyle (M), oocyst residuum (OR), polar granule (PG) and sporocyst (SP) length (L) and width (W) and their ranges and ratios (L/W); and Stieda body (SB), sub-Stieda body (SSB), para-Stieda body (PSB), sporocyst residuum (SR), sporozoite (SZ), refractile body (RB) and nucleus (N).
Other hosts: None.Type specimens: Phototypes and line drawings are deposited and available (http://r1.ufrrj.br/lcc) in the Parasitology Collection of the Coccidia and Coccidiosis Laboratory, at the Federal Rural University of Rio de Janeiro (UFRRJ), located in Seropédica, State of Rio de Janeiro, Brazil.Photographs of the type-host specimens (symbiotypes) are deposited in the same collection.The repository number is P-63/2015.
Prevalence: Five out of 27 (19%).Sporulation: Exogenous.All oocysts were passed in the feces unsporulated and were fully sporulated by day 7 in K 2 Cr 2 O 7 solution at room temperature.
Prepatent and patent periods: Unknown.Site of infection, definitive host: Unknown.Oocysts recovered from feces.
Site of infection, secondary host: Unknown.Endogenous stages, definitive host: Unknown.Endogenous stages, secondary host: Unknown.Cross-transmission: None to date.
Pathology, definitive host: Unknown.Pathology, secondary host: Unknown.Etymology: The specific epitaph is derived from the common local name for the host, which is 'peneireiro'.

Remarks
Table 1 and Table 2 show some characteristic features of Caryospora spp.described from Accipitriformes and Falconiformes respectively.Of Caryospora species listed in Table 1, only Caryospora aquilae Volf, Koudela and Modrý, 2000, Caryospora petersoni McAllister, Duszynski and McKown, 2013, and Caryospora hanebrinki McAllister, Duszynski and McKown, 2013, have oocyst measurements similar to those of C. peneireiroi.However, C. aquilae can be distinguished through the smooth surface of the SP and smaller SZ, which has N not discernible.Caryospora petersoni and C. hanebrinki, in turn, can easily be distinguished through the smooth surface of the SP, SR forming a compact mass and SZ with striations.Of the species of Caryospora described from Falconiformes (Table 2), only Caryospora megafalconis Klüh, 1994, and Caryospora biarmicusis Alyousif, Alfaleh and Al-Shawa, 2011, have oocyst measurements similar to those of C. peneireiroi.However, C. megafalconis can be distinguished through the smooth surface of the SP and SR forming a compact mass.Caryospora biarmicusis can be distinguished through the presence of OR and smaller SP with smooth surface.

Discussion
The family Falconidae comprises 66 species of raptors distributed in 11 genera.The genus Falco comprises 39 species worldwide, while other genera are exclusively Neotropical (Birdlife International, 2015).The common kestrel F. tinnunculus Linnaeus, 1758, is a widespread kestrel species, found throughout Europe, Asia and Africa.In Europe, F. tinnunculus is migratory in winter, heading for southern Europe and sub-Saharan Africa (VILLAGE, 1990;Birdlife International, 2015).