Cymothoa eremita ( Brünnich, 1783 )

Ravichandran, S., Vigneshwaran, P. & Rameshkumar, G., 2019, A taxonomic review of the fish parasitic isopod family Cymothoidae Leach, 1818 (Crustacea: Isopoda: Cymothooidea) of India, Zootaxa 4622 (1), pp. 1-99 : 19-21

Cymothoa eremita ( Brünnich, 1783)

( Fig. 1 m–o)

Oniscus oestrum Spengler, 1775: 312 , pl. 7 (figs i–k).

Oniscus eremita Brünnich, 1783: 319 .

Cymothoa Leschenaultii Leach, 1818: 352 .— Desmarest, 1825: 309.

Cymothoa Mathoei Leach, 1818: 353 .— Desmarest, 1825: 309.

Cymothoa mathoei .— Milne Edwards, 1840: 270.— Hilgendorf, 1869: 114.— Gerstaecker, 1901: 182, 258.

Cymothoa leschenaultii .— White, 1847: 109.— Miers, 1880: 461.— Ellis, 1981: 124.

Cymothoa matthaei [sic].— White, 1847: 110.— Bleeker, 1857: 22.

Cymothoa mathaei .— Lucas, 1850: 248.— Kossmann, 1880: 117, pl. 10 ( figs 1–3 ).

Cymothoa edwardsii Bleeker, 1857: 21 , 33, tab. II, fig. 12 .— Miers, 1880: 461.— Gerstaecker, 1901: 261.

Cymothoa stromatei Bleeker, 1857: 21 , 33–35 tab II, fig. 13.— Miers, 1880: 461.— Gerstaecker, 1901: 181.— Lanchester, 1902: 377.— Richardson, 1910: 22.— Hale, 1926: 214, fig. 9 (h).— Brian & Dartevelle, 1949: 184.— Sachlan, 1952: 41, 50, fig. 28.— Pillai, 1954: 15.

Cymothoa eremita .— Schiöedte & Meinert, 1884: 259, tab. VII, pl. XXV ( figs 3–13 ).— Stebbing, 1893: 354; 1910: 102.— Gerstaecker, 1901: 182.— Thielemann, 1910: 39, figs 37, 38.— Nierstrasz, 1915: 90; 1931: 135, pl. 10 ( fig. 9 ).— Monod, 1924: 100; 1933: 195; 1976: 859, figs 23–25.— Boone, 1935: 215, pl. 63.— Shiino, 1951: 81 fig. 2 (b–c).— Avdeev, 1978a: 30; 1982 b: 69.— Trilles, 1975: 987, pl. II (12–13); 1979b: 261; 1986: 627, tab. 1; 1994: 139; 2008: 23.— Bowman & Tareen, 1983: 25, fig. 20.— Radhakrishnan & Nair, 1983: 96, 105, 107.— Saito, Itani & Nunomura, 2000: 65.— Shireen, 2000: 21, figs 1–3 .— Kensley, 2001: 232.— Yu & Li, 2003: 228, fig. 4; 2003b: 267.— Trilles & Bariche, 2006: 228.— Williams & Bunkley-Williams, 2009: 557.— Trilles, Ravichandran & Rameshkumar, 2011: 446.— Rameshkumar, Ravichandran & Trilles, 2012: 191.— Hadfield, Bruce & Smit, 2013: 158 , figs 3–5 .— Rameshkumar, Ravichandran & Ramesh, 2014c: 124–128, fig. 7.—Anand Kumar, Rameshkumar, Ravichandran, Rethna Priya, Nagarajan & Kwang Leng, 2015: 206–210, fig. 2b.— Martin, Bruce & Nowak, 2016: 18–24, figs 9–13 .— Vigneshwaran, Ravichandran & Prema, 2018a: 1–7, fig. 5.

Cymothoa limbata Schiöedte & Meinert, 1884: 248 , tab. VII (Cym. XXV), figs 1, 2.— Hale, 1926: 214.— Nierstrasz, 1931: 136.— Bruce, Lew Ton & Poore, 2002: 175.

Cymothoa edwardsi .— Nierstrasz, 1931: 135.

Cymothoa sp. (an. eremita Brünnich, 1783 ) [sic].— Monod, 1934: 13, pl. 27a–b, 30b.

Cymothoa erimitae (typographical error?).— Sachlan, 1955: 31.

Cymothoa cinerea Bal & Joshi, 1959: 567 , pl. 2 ( figs 1–5 ).— Kensley, 2001: 232.

Cymothoa cinerius .— Joshi & Bal, 1960: 446.

Cymothoa mathieui .— Ellis, 1981: 124.

Cymothoa krishnai Jayadev Babu & Sanjeeva Raj, 1984: 818–823 , pl. 1 (fig. 1k–v).— Rattan & Parulekar, 1998: 407–410, fig. 4 [new synonymy].

Cymothoa leaschenaultii [sic].— Kensley, 2001: 232.

Cymothoa epimerica .— Trilles, 2008: 23 (SMF–567).

Type and type locality. The holotype Cymothoa eremita , deposited at The Zoological Museum, University of Copenhagen (ZMUC-CRU-10078) and was recently figured by Hadfield et al. (2013), it would ideally be from the type locality, Pondicherry, India Jayadev Babu & Sanjeeva Raj’s Indian type specimens of Cymothoa krishnai are not extant.

Material examined. 2 ovig. females (25, 31 mm), from the buccal cavity of black pomfret Parastromateus niger (Bloch, 1795) ( CAS / MBRM C- 87– C- 88), 1 non ovig. female (30 mm) from Peprilus paru ( Linnaeus, 1758) , Pazhaiyar 26 May 2013, ( CAS / MBRM C- 89) coll. G. Rameshkumar; 1 ovig. female (29 mm), Parangipettai, 22 July 2017, from Parastromateus niger , coll. S. Ravichandran ( ZSI / MBRC D1-532), the southeastern coast of India.

Remarks. Hadfield et al. (2013) redescribed and diagnosed C. eremita from the female holotype (ZMUC-CRU-10078) and Martin et al. (2016) examined C. eremita from the non ovig. female (MTQ W30413). C. eremita can be identified by pereonite 1 anterolateral margins extending nearly half the length of cephalon; cephalon subtruncate; pleon as wide as pereon; uropods which do not reach the posterior margin of the pleotelson; pereopod 7 with a bulbous protrusion on ischium; and small horn-like structures on the posterolateral margins of pereonite 1. Indian specimen C. eremita is morphologically similar to Hadfield et al. (2013) and Martin et al. (2016) examined specimens.

The Indian specimen is most similar to the syntype specimen of C. mathoei (illustrated by Hadfield et al. 2013). The Indian specimen has a wider body, 1.9 times longer than wide (as opposed to 2.4 times longer than wide); Coxae 2 and 3 with posteroventral margin angles subtruncate; 4–7 rounded; more visible cephalon with anterolateral margins of pereonite 1 minute; Pereopod 7 large proximal bulbous protrusion; merus proximal margin with slight bulbous protrusion; dactyli slender.

Cymothoa eremita has been the most widely applied name of the genus. Miers (1880) examined a large number of Bleeker’s (1857) collection of isopods and noticed a large variation in the anterolateral lobes of the first pereonite and on the basis of the last pereopod. Miers (1880) furthered explained how no difference could be seen between Leach’s (1818) C. leschenaultii (single specimen from Ponducherry) and Bleeker’s (1857) C. stromatei and C. edwardsii , synonymising all three species. Kossmann (1880) later synonymised C. mathoei with C. eremita and Schiöedte & Meinert (1884) synonymised C. stromatei with C. eremita .

Cymothoa cinerea Bal & Joshi, 1959 was described from India with the authors noting that the species was very similar to Cymothoa stromatea [sic] parasitic on Parastromateus niger , differing in having a longer thorax, shorter and tuberculate abdomen and slightly punctuate sides of its body. Both species were collected from the same host species off India. Hadfield et al. (2013) stated that this Cymothoa cinerea Bal & Joshi, 1959 is a junior synonymy of C. eremita . Hadfield et al. (2013) stated that the C. eremita is a common species in the Indian and Pacific Oceans. A number of species have also already been synonymized with C. eremita and recently two of those ( C. mathoei and C. leschenaultii ) were examined as and their status as junior synonyms confirmed by Hadfield et al. (2013).

Jayadev Babu & Sanjeeva Raj’s figures and drawings of Cymothoa krishnai are similar to the holotype illustrations of Hadfield et al. (2013) and our present non-type material, showing characteristics of the anterolateral projections which extend to half the length of the cephalon; truncate anterior margin of the cephalon; pleon as wide as pereon; uropods which do not reach the posterior margin of the pleotelson; ischium on pereopod 7 with a bulbous protrusion; and small lateral projections on the posterolateral margins of pereonite 1. Type specimen recorded from Pulicat Lake, India, whereabouts the type material for these species remains unknown. Jayadev Babu & Sanjeeva Raj’s description and illustrations nonetheless support a synonymy with C. eremita .

Colour. Ivory white ( Martin et al. 2016).

Size. Ovig. females 19–44 mm; non ovig. females 17–35 mm; males 9–24 mm ( Schiöedte & Meinert 1884; Bal & Joshi 1959; Monod 1976; Trilles 1979b; Shireen 2000).

Distribution. Known from the Indian Ocean and Indo–Pacific regions. For locality details see Hadfield et al. (2013) and Trilles (1994, 2008).

Host. Known from 10 host families (family Aulopidae , Carangidae , Haemulidae , Mugilidae , Psettodidae , Serranidae , Siganidae , Sphyraenidae , Stromateidae , Tetraodontidae ). For fish host species details, see Hadfield et al. (2013). Later Martin et al. (2016) reported Pristipomoides multidens (Day, 1871) (Lutjanidae) .

Figures

FIGURE 1. a–c, Anilocra dimidiata Bleeker, 1857, female (24 mm), (ZSI/MBRC D1-529); d–f, Catoessa boscii (Bleeker, 1857), female (17 mm), (ZSI/MBRC D1-530); g–i, Ceratothoa angulata (Richardson, 1910), female (29 mm), (ZSI/MBRC D1-533); j–l, Cymothoa bychowskyi Avdeev, 1979, female (27 mm), (CAS/MBRM C-87); m–o, Cymothoa eremita (Brünnich, 1783), female (29 mm), (ZSI/MBRC D1-532); p–r, Cymothoa frontalis Milne Edwards, 1840, female (25 mm), (CAS/MBRM C-89).

FIGURE 2. a–c, Cymothoa indica Schiöedte & Meinert, 1884, female (25 mm), (CAS/MBRM C-97); d–f, Cymothoa parupenei Avdeev, 1979, female (25 mm), (ZSI/MBRC D1-533); g–i, Glossobius impressus (Say, 1818) female (26.7 mm) (ZSI/MBRC D1-554); j–l, Joryma hilsae Rameshkumar et al. 2011, female (20 mm), (ZSI/MBRC D1-535); m–o, Joryma sawayah Bowman & Tareen, 1983, female (14 mm), (ZSI/MBRC D1-536); p–r, Lobothorax typus Bleeker, 1857, female (23 mm), (ZSI/MBRC D1-537).

FIGURE 3. a–c, Mothocya collettei Bruce, 1986, female (25 mm), (CAS/MBRM C-149); d–f, Mothocya melanosticta (Schiöedte & Meinert, 1884), female (24 mm), (ZSI/MBRC D1-538); g–i, Mothocya plagulophora (Haller, 1880), female (28 mm), (ZSI/MBRC D1-539); j–l, Mothocya renardi (Bleeker, 1857), female (30 mm), (ZSI/MBRC D1-540); m–o, Nerocila arres Bowman & Tareen, 1983, female (28 mm), (CAS/MBRM 475–476); p–r, Nerocila depressa Milne Edwards, 1840, female (30 mm), (ZSI/MBRC D1-541).

FIGURE 4. Mothocya plagulophora (Haller, 1880), female (28 mm), (ZSI/MBRC D1-539). a, dorsal view; b, lateral view; c, mouthpart with antennula and antenna; d, antennula; e, antenna; f, mandible; g, maxillula; h, maxilliped; i, maxilla.

FIGURE 5. Mothocya plagulophora (Haller, 1880), a, male (13 mm) (CAS/MBRM C-167) dorsal view; b–m, female (28 mm), (ZSI/MBRC D1-539); b–f, pereopod 1, 2, 4, 6 & 7; g–k, pleopods 1–5; l, uropod; m, brood pouch.

FIGURE 6. Nerocila depressa Milne Edwards, 1840, female (30 mm), (ZSI/MBRC D1-541). a, dorsal view; b, lateral view; c, forns; d, antennula; e, antenna; f, mandible; g, maxillula; h, maxilla; i, maxilliped.

FIGURE 7. Nerocila depressa Milne Edwards, 1840, female (30 mm), (ZSI/MBRC D1-541). a–e, pereopods 1–3, 5 & 7; f–j, pleopods 1–5; k, uropod.

FIGURE 8. a–c, Nerocila exocoeti Pillai, 1954, female (25 mm), (ZSI/MBRC D1-542); d–f, Nerocila longispina Miers, 1880, female (22 mm), (ZSI/MBRC D1-543); g–i, Nerocila loveni Bovallius, 1887, female (20 mm), (ZSI/MBRC D1-544); j–l, Nerocila phaiopleura Bleeker, 1857, female (26 mm), (ZSI/MBRC D1-545); m–o, Nerocila poruvae Rameshkumar et al. 2011, female (24 mm), (ZSI/MBRC D1-546); p–r, Nerocila serra Schiöedte & Meinert, 1881, female (28 mm), (CAS/MBRM–661).

FIGURE 9. Nerocila loveni Bovallius, 1887, female (20 mm), (ZSI/MBRC D1-544). a, dorsal view; b, lateral view; c, forns; d, uropod.

FIGURE 10. Nerocila loveni Bovallius, 1887, female (20 mm), (ZSI/MBRC D1-544). a, antennula; b, antenna; c, mandible; d, maxillula; e, maxilla; f, maxilliped; g, maxilliped article 3;

FIGURE 11. Nerocila loveni Bovallius, 1887, female (20 mm), (ZSI/MBRC D1-544). a–g, pereopod 1–7.

FIGURE 12. Nerocila loveni Bovallius, 1887, female (20 mm), (ZSI/MBRC D1-544). a–e, pleopods 1–5.

FIGURE 13. a–c, Nerocila sundaica Bleeker, 1857, female (24 mm), (ZSI/MBRC D1-547); d–f, Nerocila trichiura (Miers, 1877), female (30 mm), (ZSI/MBRC D1-548); g–i, Norileca indica (H. Milne Edwards, 1840), female (26 mm), (ZSI/MBRC D1-549); j–l, Norileca triangulata (Richardson, 1910), female (16 mm), (ZSI/MBRC D1-550); m–o, Ryukyua circularis (Pillai, 1954), female (13 mm), (CAS/MBRM C-227); p–r, Ryukyua globosa Williams & Bunkley-Williams, 1994, female (14 mm), (ZSI/MBRC D1-552).