Philometra lateolabracis (NEMATODA: PHILOMETRIDAE) IN Epinephelus costae (OSTEICHTHYES, SERRANIDAE): FIRST MOLECULAR IDENTIFICATION OF THE HISTOZOIC PARASITE FROM ISKENDERUN BAY, NORTHEAST MEDITERRANEAN SEA
This is the first study on molecular identification of Philometra lateolabracis Yamaguti, 1935 (Nematoda: Philometridae) in goldblotch grouper (Epinephelus costae Steindachner, 1878) in the Northeastern Mediterranean Sea. A total of 32 E. costae were sampled in March 2012 (before the breading season) from Iskenderun Bay (35- 3635- 36 P. lateolabracis were only extracted from the goldblotch grouper ovaries and detected as a histozoic parasite. Identification of philometrids is usually very difficult and problematic because of their biological and morphological features. Today numerous molecular methods have been used for the identification of cryptic stages of various parasites including the philometrids. In this study we amplified and sequenced the ITS region of P. lateolabracis for molecular identification of this nematod. The status in infestation rates (mean prevalence P= 42.31%, Ni=11, Nu-i=21) and variations of total lengths and live weights of infested fish (TLi=25.93cm, Wi=292.55g) and non-infested fish (TLh=25.77cm, Wh= 288.81g) were calculated. This study suggested that this is a quick and simple method for the P. lataelabracis in case of morphological identification is unreliable and unpractical.
The philometrid nematode was reported first by Genc in 2002 from four species of groupers including E. costae- in Iskenderun Bay. Later in 2004 Moravec and Genc idenfied histozoic parasite as a P. lateorabracis Yamaguti, 1935. In response to Moravec and Gencs study, Quiazon at al. claimed that the previous identification was incorrect based on morphological parameters and instead it would be P. jordanoi L1951. Threfore, the current study is designed to investigate the molecular identification of P. lateolabracis in E. costae Steindachner, 1878.
Analyses were conducted using the Kimura 2-parameter model. Number of base substitutions per site from between sequences were used to estimate the genetic divergence level. Standard error estimates were shown above the diagonal (Table 1) Evolutionary history among our sample and previously recorded samples was inferred using the Neighbor-Joining method. Evolutionary distances were computed using Kimura 2-parameter model. Bootstrap tests of 1000 replicates was used to confirm the reliability of the tree (Fig 1).
The philometrid nematode was reported first by Genc in 2002 from four species of groupers including E. costae- in Iskenderun Bay. Later in 2004 Moravec and Genc idenfied histozoic parasite as a P. lateorabracis Yamaguti, 1935. In response to Moravec and Gencs study, Quiazon at al. claimed that the previous identification was incorrect based on morphological parameters and instead it would be P. jordanoi L1951. Threfore, the current study is designed to investigate the molecular identification of P. lateolabracis in E. costae Steindachner, 1878.
Analyses were conducted using the Kimura 2-parameter model. Number of base substitutions per site from between sequences were used to estimate the genetic divergence level. Standard error estimates were shown above the diagonal (Table 1) Evolutionary history among our sample and previously recorded samples was inferred using the Neighbor-Joining method. Evolutionary distances were computed using Kimura 2-parameter model. Bootstrap tests of 1000 replicates was used to confirm the reliability of the tree (Fig 1).