Spirophilometra endangae, Dewi, Kartika & Palm, Harry W., 2013

Dewi, Kartika & Palm, Harry W., 2013, Two new species of philometrid nematodes (Nematoda: Philometridae) in Epinephelus coioides (Hamilton, 1822) from the South Bali Sea, Indonesia, Zootaxa 3609 (1), pp. 49-59 : 50-53

Spirophilometra endangae sp. nov.

Taxonomy summary

Type host: Epinephelus coioides (Hamilton, 1822) ( Serranidae ; Perciformes )

Site of infection: fins

Type locality: South Bali Sea, Indonesia

Date of collection: July 2008

Collector: Sonja Kleinertz (Aquaculture and Sea-Ranching, Faculty of Agricultural and Environmental Sciences, University Rostock, Germany)

Specimens deposited: Holotype (MZB Na 485), 5 female paratypes (MZB Na 486)

Host: Epinephelus coioides (Hamilton, 1822) ( Serranidae ; Perciformes )

Etymology: The species is named after Endang Purwaningsih (Museum Zoologicum Bogoriense), who guided Kartika Dewi in nematode taxonomy. She also enabled Harry W. Palm to carry out fish parasitological studies at the MZB, Research Center for Biology-LIPI Cibinong, during his stay as a long-term guest lecturer at the Institute Pertanian Bogor (IPB) between 2000 and 2005.

Gravid female (n=6)

Description. Total body length 10.5–21.6 mm (13.7 mm), maximum width 400–680 (478) Oral aperture circular, small, surrounded by a pair of inconspicuous small amphids; 14 spherical and oval small cephalic papillae, arranged in two circles; external circle formed by four pairs of submedian papillae, internal circle by two pairs of sub median papillae and one pair of lateral papillae. Bottom mouth formed by flat surface of three oesophageal sectors. Mouth diameter 10.7 and 12.1. Nerve ring 150–250 (178) from anterior end. Anterior oesophagus swollen near mouth forming muscular bulb. Overall length of oesophagus 710–800 (734), representing 6.2–11.0 % (8.1%) of TBL (total body length), consisting bulb 59–70 (63) long, 48–68 (56) wide and narrow, muscular oesophagus 640–30 (671) long, 45–68 (55) wide. Oesophageal gland extending anteriorly from posterior end of oesophagus to short distance posterior to bulb. Nucleus of oesophageal gland 570–645 (592) from anterior end, distance between oesophagus bulb end and oesophageal gland 16–18 (17). Small ventriculus present opening into intestine through valve. Diameter of one oesophageal sector 15. Deirid not seen. Intestine narrow, attached subventrally to body wall near posterior extremity. Entire body covered with numerous minute cuticular spines, mostly not arranged into transverse rows. Spines broad at base with pointed end. Some spines rudimentary, with round-shape in middle part of body. Length of spines in middle part of body 2.9–3.7 long by 1.9–2.4 wide and 4.5–4.7 long at the posterior end. Distribution of the spines more distinct in the middle and anterior part of body, but scattered in the mid body. Body end bluntly rounded, with two lateral caudal projections. Posterior end of body narrow, 102.8 wide. Uterus occupying most of space of the body, extending posteriorly to nerve ring. Larva with smooth cuticle, and sharply pointed tail, 320–340 long, 12–14 wide.

Male: unknown

Remarks. This new species belongs to the genus Spirophilometra because the entire cuticle of the gravid female is covered with minute spines. Three valid congeners hitherto have been recorded in the genus Spirophilometra , i.e. S. eichleri Parukhin, 1971 , S. pacifica (Moravec, Santana-Pineros, Gonzales-Solis, Torres- Huerta, 2007) and S. centropomi (Caballero, 1974) (Moravec 2006; Moravec et al. 2007). S. endangae sp. nov. differs from S. eichleri in total body length (10.5–22.76 mm versus 5.43 – 5.51mm), in the presence versus absence of an anterior bulbous inflation and the site of infection in the host (fins versus spleen and ovaries). S. endangae sp. nov. can be distinguished from S. centropomi in the larger body size of the gravid females (10.5–22.76 mm versus 3.3–6.2 mm) and in the shape of the anterior bulbous inflation. The bulb in S. centropomi is claviform and the length of the bulb is two times the width (42–51 long, 25 wide). The bulb of S. endangae sp. nov. is almost spherical [59–70 (63) long, 48–68 (56) wide]. This species also differs from S. pacifica in the structure and arrangement of the spines on the cuticle in the middle part of the body (widely spaced spines versus densely transversely striated spines; many versus few rounded spines). Spirophilometra endangae sp. nov. can be differentiated from S. pacifica in the infection site of the adult worms in the host (fins versus mouth cavity), the type host ( Serranidae versus Centropomidae ) and in the geographical distribution of the host (Indo-West Pacific and Mediterranean coast versus the Chantuto-Panzacola system, Mexico).

Comparison was also made with the description of Philometra pinnicola (Yamaguti, 1935) , a species which was described from the fins of E. akaara from Inland Japan. The total length of the oesophagus is 3.375%– 4.54% of the total body length in P. pinnicola versus 4.03–7.23% (5.79%) in the present species, and the width of the larva is 20–25 in P. pinnicola versus 12–14 in Spirophilometra endangae sp. nov. (Moravec 2006). Although S. endangae sp. nov. has been described without the male specimens, this species can be clearly identified based on the general female morphology and a relatively high degree of host specificity in philometrids.

PLATE 1. Spirophilometra endangae sp. nov. (SEM figures): A. Cephalic end with distribution of the cephalic papillae of a mature female (apical view), B. Cephalic papilla of a mature female (apical view, higher magnification), C. Mouth of the gravid female (apical view), D. Spines in the cuticle of the mid body, E. Posterior end, F: Spines at the posterior end. c - cephalic papilla; a - amphid; cp - caudal projection.

PLATE 2. Spirophilometra endangae sp. nov. (line drawings): G. Anterior end of the body (ventral view), H. Anterior part (ventral view), I. Cephalic end (apical view), J. Posterior part (ventral view), K. caudal end of the gravid female (dorsoventral view), L. Caudal end of the gravid female (lateral view).