New species of Delicata (Molineidae: Anoplostrongylinae) parasite of Cabassous tatouay (Desmarest, 1804) from the Atlantic Forest, Rio de Janeiro, Brazil

A new species of nematode parasite of the genus Delicata (Molineidae: Anoplostrongylinae) is described from the small intestine of a road-killed Greater Naked-tailed Armadillo Cabassous tatouay (Cingulata: Chlamyphoridae) on the BR-040 highway in Rio de Janeiro state, Brazil. The genus Delicata includes 13 species of parasitizing armadillos and anteaters distributed in Brazil, Argentina, and Trinidad and Tobago. The present species is distinguished from almost all species of Delicata by the longest length of the body, except for D. khalili and D. appendiculata. However, these can be distinguished from each other by the length of the spicules. The species that closely resembles, Delicata tatouay n. sp. is D. speciosa, but it can be distinguished by a robust branch from rays 2 and 3, rays 4 larger, and rays 8 longer compared to those of the new species. The new species is the only one with a tail, characterized by a terminal spine with rattlesnake tail-like transversal striations.

The greater naked-tailed armadillo, Cabassous tatouay (Desmarest, 1804), can be found inhabiting Uruguay, northeastern Argentina, eastern Paraguay, and south, central, and northeastern Brazil (4).It is the largest species of the genus, measuring approximately 48 cm (head-body length) and weighing approximately 4.8 kg (5,6).In Brazil, it occurs in the Atlantic Forest, Cerrado, Caatinga, Pampas, and Pantanal near the transition to the Cerrado savanna (4,7).They are solitary and insectivorous (8, 9), feeding on terrestrial ants and termites (10,11).The species uses both forested and open areas but prefers forested habitats (5,12).This is a poorly known species of armadillo, with relatively few records in Brazilian museums (13).In the IUCN Red List, it is listed as the least concern (12), whereas in the Brazilian Red Book, it is considered data deficient (14).The main threats to the species are probably deforestation and fire, as well as hunting and persecution (14).
The use of carcasses of wild road-killed vertebrates for scientific purposes has provided discoveries for science (15)(16)(17).Considering that the greater naked-tailed armadillo is poorly known, the use of samples from these animals is an opportunity to contribute to scientific development, including helminthology, given that there is almost no information regarding helminths from this host (18).
During a parasitological survey in the small intestine of one C. tatouay road-killed on the BR040 highway in Rio de Janeiro state, Brazil, a new species of the nematode Delicata was collected and described herein.

Materials and methods
One road-killed adult C. tatouay was collected in April 2011 on the federal BR-040 highway, 38 km, in Areal municipality, as part of the project "Caminhos da Fauna." The project "Caminhos da Fauna" started in 2006, is still in progress, and comprises the pioneering study in the monitoring of road-killed vertebrates in the state of Rio de Janeiro.The database used in the study comes from the monitoring of the road-killed vertebrate along a 180.4 km stretch of the BR-040 (from 125.2 km in the municipality of Duque de Caxias, state of Rio de Janeiro, to 773.5 km in the municipality of Juiz de Fora, state of Minas Gerais).
Carcass collections are included in the SISBIO License Number: 30727-9.The animal carcasses used in this study meet and are in accordance with operation license No. 1187/2013 and authorization for capture, collection, and transport of biological material -Abio (first renewal and third rectifier) 514/2014.
The abdominal and thoracic cavities of the host specimen were opened, and the organs were placed separately in Petri dishes, washed in saline solution (0.9% sodium chloride), and dissected under a stereomicroscope to remove the small helminths.Collected nematodes were conserved in 70° ethanol.Ten specimens were clarified in a 50% alcohol/glycerin solution, mounted as temporary slides, and examined under a Zeiss Standard 20 light microscope.Drawings for morphologic and morphometric analyses were made with the aid of a camera lucida, and the images were obtained with a digital camera (Olympus DP-12) and a light microscope (Olympus BX-51).Transversal sections on the anterior, middle, and posterior parts of the body of males and females were made in order to study the synlophe.The nematodes were identified following Anderson et al. (19), Travassos (2), and Durette-Desset (20).The measurements are given in micrometers unless otherwise indicated.Means are followed by the range between brackets.The holotype, allotype, and paratypes were deposited in the helminthological collection of the Oswaldo Cruz Institute (CHIOC) in Rio de Janeiro.

Results
General: Small, slender, coiled body, with sexual dimorphism (female larger than male); presence of a cephalic vesicle.Rounded mouth opening in apical view, surrounded by two amphids, six external labial papillae.Excretory pore situated between 42 and 60% in relation to esophagus length (Figure 1A).Deirids situated anterior to excretory pore.
Synlophe (studied in one male and one female): ridges appear longitudinally along the body, beginning posterior to the cephalic vesicle in both sexes.It is not observed at the proximal region of the caudal bursa in males and at the posterior extremity in females.Synlophe with 11 ridges in females and 12 in males at the level of the esophagus (Figures 2A,D); 12 ridges at mid-body in both sexes (Figures 2B,E); 12 ridges anterior to the anus in females and anterior to the caudal bursa in males (Figures 2C,F).Ridges at mid-body are slightly unequal in size in both males and females, with smaller ridges oriented from the ventral right axis and to the ventral left and from the dorsal right quadrant to the dorsal left.
Etymology: The species epithet is due to the specific name of the host.

Discussion
The new species belongs to the genus Delicata, presenting a cephalic end without a cuticular ring and a lack of cuticular plates, a female amphidelphic vulva far from the anus, a tail rounded with a caudal spine, a male with ray 5 at the same length or longer than ray 6, the presence of small post-cloacal papillae 7 at the caudal bursa, and parasites of the intestine of Xenarthra (20).This is the first species belonging to the genus Delicata described by Cabassous tatouay.
The present species is distinguished from almost all other species of Delicata by the longest length of the body, except for D. khalili and D. appendiculata, which show similar lengths.In addition, Delicata tatouay n. sp.differs from D. soyerae, D. cameroni, D. abbai, D. delicata,  1, 2).In contrast, the species D. ransoni, D. khalili, D. variabilis, and D. perronae have larger spicules than the new species.
The most similar species is D. speciosa, but it can be differentiated because it presents a robust branch from rays 2 and 3, rays 4 larger, and rays 8 longer from those of Delicata tatouay n. sp.Moreover, the synlophe at the middle body of D. speciosa is markedly distinguished from D. tatouay n. sp.The first presents only four ridges situated at the ventral side and two small lateral cuticular dilatation, and the second presents 12 ridges (six ventral and six dorsal) in both sexes.Finally,      Delicata tatouay n. sp. is the only species presenting a terminal spine in the tail with rattlesnake tail-like transversal striations.Durette-Desset (20) characterized the synlophe of genus Delicata as having two lateral alae.However, Ezquiaga et al. (1) questioned this feature, suggesting not to use this character to propose a new genus once there is no synlophe of all known species, mainly D. delicata, that represents the type species of the genus.In addition, the known synlophe of D. soyerae, D. perronae, D. abbai, D. ransomi, and Delicata tatouay n. sp.have demonstrated great variability in the number of ridges.In fact, a review of the genus is required to elucidate these generic diagnostic features.
Records of the greater naked-tailed armadillo are scarce in some regions (4,27), although it is considered globally of "least concern" (12,28).In addition, there is almost no information about the helminth fauna of this host (18).Indeed, there is still an important lack of knowledge about parasites infecting wildlife (29), especially in highly diverse countries such as Brazil.Using road-killed vertebrates to identify new species of helminths is important not only for helminthology, but it is also essential to develop ecological research on host-parasite interaction.

FIGURE 2
FIGURE 2 Light microscopy drawing of synlophe in transverse sections of the body from Delicata tatouay n. sp.(A-C) Female.(A) At the oesophago-intestinal junction; (B) at mid-body; (C) at level of the anus.(D-F) Male.(D) At the oesophago-intestinal junction; (E) at the mid-body; (F) at the level of the near caudal bursa.Scale bars: (A-F) = 50 μm.

TABLE 1
Morphometric data on male species of the genus Delicata in America.

TABLE 2
Morphometric data on female species of the genus Delicata in the Americas.