Encrasicholina macrocephala, Hata, Harutaka & Motomura, Hiroyuki, 2015

Hata, Harutaka & Motomura, Hiroyuki, 2015, A new species of anchovy, Encrasicholina macrocephala (Clupeiformes: Engraulidae), from the northwestern Indian Ocean, Zootaxa 3941 (1), pp. 117-124 : 118-122

Encrasicholina macrocephala sp. nov.

New English name: Largehead Anchovy ( Figs. 1 –5; Tables 1–3)

Holotype. MNHN 2014-0152, 44.6 mm SL, Djibouti, Republic of Djibouti, 11°33′N, 43°10′E, collected by H. Coutiere.

Paratypes. 16 specimens, 42.3–55.7 mm SL. ANSP 83365, 4 specimens, 48.6–55.7 mm SL, Batina Coast, Sultanate of Oman, 22 Feb. 1944, collected by H. Steinitz; HUJ 14395, 5, 42.3–50.9 mm SL, Sultanate of Oman, Jan. 1944, collected by D. Pitzerld; KAUM –I. 65338, 47.6 mm SL, KAUM –I. 65339, 48.8 mm SL, and MNHN 2014-0153, 5, 43.7–53.1 mm SL, collected with the holotype.

Diagnosis. A species of Encrasicholina with the following combination of characters: dorsal and anal fins with three unbranched rays; total pectoral-fin rays 11–14 (modally 13); pseudobranchial filaments 15–18; gill rakers on 1st arch 17–20 (19) in upper series, 21–25 (23) in lower series, 40–45 (42) in total; prepelvic scutes 5–6 (5); head large, its length 29.5–31.7% (mean 30.4%) of SL; upper jaw long, its length 21.3–23.5% (mean 22.2%) of SL and its posterior tip extending beyond posterior margin of preopercle; lower jaw long, its length 19.5–21.2% (mean 20.3%) of SL; D–P1 short, 83.2–95.2% (mean 89.8%) of HL.

Description. Data for the holotype are presented first, followed by paratype data in parentheses. Body cylindrical, elongate, deepest at dorsal-fin origin. Dorsal profile of head and body slightly convex from snout tip to dorsal-fin origin, straight along dorsal-fin base. Ventral profile of head and body slightly convex from lower-jaw tip to pelvic-fin insertion, slightly convex to straight from pelvic-fin origin to anal-fin origin, and almost straight along anal-fin base. Dorsal and ventral profiles of caudal peduncle slightly concave. Belly slightly rounded, covered by 5 (or 6) sharp needle-like scutes anterior to insertion of pelvic fins. Postpelvic and predorsal scutes absent. Anus situated just anterior to anal-fin base. Caudal peduncle compressed; its depth greater than eye diameter. Head large, compressed. Snout tip rounded; snout length less than orbit diameter. Interorbital width less than orbit diameter. Mouth inferior, ventral to body axis; large, extending backward beyond posterior margin of eye. Lower jaw slender, shorter than upper jaw, 93.0% (89.4–94.9%) of upper-jaw length. Posterior tip of maxilla pointed, projecting beyond second supra-maxilla and posterior margin of preopercle. Single row of conical teeth on each jaw and on palatines. Small conical teeth in patch on vomer. Eye lateral on head, located dorsal to horizontal through pectoral-fin insertion; eye large, covered with adipose eyelid; visible in dorsal and ventral views. Eye and pupil round. Orbit elliptical. Nostrils close to each other, positioned anterior to orbit. Posterior margin of preopercle smooth. Subopercle with rounded posterior margin. Opercular membrane without serrations. Interorbital space flat. Pseudobranchial filaments present, length of longest filament less than eye diameter. Posterior frontal fontanelles on top of head near occiput open. Gill rakers slender, rough; long; visible from side of head when mouth opened. Distance between pectoral-fin and pelvic-fin insertions subequal to distance between pelvic-fin insertion and analfin origin. Isthmus muscle short, not reaching anteriorly to posterior border of gill membrane, but preceded by exposed urohyal between gill membranes. Gill membrane not broadly joined over isthmus. Scales cycloid, thin, and deciduous, except for prepelvic scutes. No scales on head. Lateral line absent. No scales on fins except for broad triangular sheath of scales on caudal fin. Pectoral-fin axillary scale shorter than pectoral fin (absent in most paratypes, probably lost when collected or during storage). Pelvic-fin axillary scale absent in holotype (when present in some paratypes scale smaller than pectoral-fin axillary scale). Dorsal-fin origin posterior to vertical through base of last pelvic-fin ray, slightly posterior to middle of body. Dorsal-fin base short, its length 69.5% (68.1–87.8%) of anal-fin base length. Dorsal and anal fins with three anteriormost rays unbranched. First dorsal-fin ray and first anal-fin ray minute. Three anteriormost dorsal-fin rays and three anteriormost anal-fin rays closely spaced. Posterior tip of depressed dorsal fin reaching to vertical through anal-fin origin. Anal-fin origin posterior to vertical through base of last dorsal-fin ray. Posterior tip of depressed anal fin not reaching to caudal-fin base. Caudal fin forked. Uppermost pectoral-fin ray unbranched, inserted below midline of body. Posterior tip of pectoral fin not reaching to vertical through pelvic-fin origin; pectoral-fin rays damaged in holotype (1st or 2nd rays longest in some paratypes). Pelvic fin shorter than pectoral fin; pelvic-fin insertion anterior to vertical at dorsal-fin origin. Posterior tip of depressed pelvic fin not reaching to anus, reaching vertical through base of 6th (6th–9th) dorsal-fin ray.

Encrasicholina macrocephala n. sp. Encrasicholina devisi

Holotype Paratypes Holotype Non-types

Djibouti Djibouti and Australia Indo-West

Oman Pacific

MNHN AMS IB.

2014-0152 n = 16 Modes 609 n = 93 Modes

Standard length (mm) 44.6 42.3–55.7 44.0 27.0–78.4

Branched pectoral-fin rays Pseudobranchial filaments 10 11 12 13 14 15 16 17 18 19 20 21 22

E. macrocephala n. sp. n = 14 2 6 H 7 1 n = 15 1 6 H 6 4 E . devisi n = 78 28 45 5 n = 65 8 22 19 9 7 H Includes count of holotype.

Distribution. Currently known only from the southern Red Sea (off Djibouti) and the Arabian Sea (off the Sultanate of Oman).

Etymology. The specific name “ macrocephala ” is derived from the Greek meaning “large head”, in reference to the relatively large head.

Remarks. Seven nominal species are known to be attributed to the genus Encrasicholina ( Whitehead et al. 1988) . Encrasicholina macrocephala is most similar to E. devisi (Whitley 1940) in sharing three unbranched rays in the dorsal and anal fins and in having a long upper jaw with its posterior tip extending beyond the posterior margin of the preopercle. However, the head of E. macrocephala is longer than that of E. devisi [head length 29.5–31.7% of SL (mean 30.4%) vs. 25.4–28.9% (26.7%) in E. devisi ; Fig. 2 A, Table 2 ]. In E. macrocephala , the D–P1 is shorter than that of E. devisi [83.2–95.2% (mean 89.8%) vs. 97.6–126.1% of HL (mean 111.0%); Fig. 2 B, Table 2 ]. In addition, lengths of the upper and lower jaws of E. macrocephala trend longer than those of E. devisi [upper-jaw length 21.3–23.5% of SL (mean 22.2%) vs. 14.6–21.3% (18.9%); Fig. 2 C, Table 2 ; lower-jaw length 19.5–21.2% of SL (mean 20.2%) vs. 14.2–19.5% (17.5%); Fig. 2 D, Table 2 ]. The numbers of branched pectoral-fin rays and pseudobranchial filaments also distinguish E. macrocephala (11–14 and 15–18 respectively) from E. devisi (13–15 and 18–22 respectively) ( Table 3).

Although Hata et al. (2012) redescribed the holotype of Amentum devisi as having 16 upper gill rakers on the first gill arch, 13 upper gill rakers on the second gill arch, 9 lower gill rakers on the fourth gill arch, and 43 lateralline scales, these data were incorrect; the correct data for these counts are 19, 15, 10, and 39, respectively ( Table 1).

Encrasicholina macrocephala is easily distinguished from E. punctifer Fowler 1938 [with Stolephorus buccaneeri Strasburg, 1960 , a junior synonym ( Wongratana 1983; Whitehead et al. 1988; Wongratana et al. 1999).], E. oligobranchus ( Wongratana 1983) , and E. purpurea (Fowler 1900) by its long upper jaw, with posterior tip extending beyond the posterior margin of the preopercle (vs. posterior tip of upper jaw not reaching to posterior margin of preopercle in the other three species; Strasburg 1960; Whitehead et al. 1988; Wongratana et al. 1999). Encrasicholina macrocephala also differs from E. oligobranchus by having more gill rakers [gill rakers on 1st arch 17–20 (modally 19) in upper series, 21–25 (23) in lower series vs. 13–14, 17–18, respectively; Wongratana 1983; Whitehead et al. 1988; Wongratana et al. 1999]. The new species differs from S. pseudoheterolobus Hardenberg 1933 [regarded as a junior synonym of E. heteroloba (Rüppell 1837) ; Whitehead et al. 1988; Wongratana et al. 1999] by having a larger head [head length 29.5–31.7% of SL (mean 30.4%) vs. 23.8–26.3% in syntypes of S. pseudoheterolobus ; Hardenberg, 1933a, b, 1934]. Although most meristic characters of E. macrocephala agree well with those of E. heteroloba , the former differs in having three unbranched rays in the dorsal and anal fins [vs. 2 or rarely 1 unbranched ray; Whitehead et al. 1988; Wongratana et al. 1999; Hata et al. 2012; this study].

Comparative material examined. Encrasicholina devisi (94 specimens, 27.0– 78.4 mm SL): AMS IB. 609, holotype of Amentum devisi , 44.0 mm SL, Cape York, Queensland, Australia, 10°07′S, 142°40′E, 1885; AMS I. 21425-001, 3 specimens, 34.5–37.4 mm, Pellew Group, Gulf of Carpentaria, Northern Territory, Australia, 15°31′S, 136°53′E, Aug. 1923; BMNH 1989.2.2.141-162, 21, 32.6–52.3 mm, Makassar, Sulawesi, Indonesia, 6 Dec. 1978; BMNH 1992.8.13.426-431, 6, 52.1–59.7 mm, Indonesia, 1 Jan. 1976; FMNH 120780, 5, 64.6–71.7 mm, FMNH 120781, 4, 68.9–78.4 mm, Donggang, Pingtung, Taiwan, 22°28ʹ00ʺS, 120°26ʹ21ʺE, 10 Sept. 2009; KAUM –I. 16932, 75.2 mm, off Kuala Terengganu, Terengganu, Malaysia, 5°22′N, 103°15′E, 11 Dec. 2008; KAUM –I. 35943, 57.0 mm, Uchinoura Bay, Kimotsuki, Kagoshima, Japan, 31°17′N, 131°05′E, 26 Jan. 2011; KAUM –I. 52176, 62.0 mm, Uchinoura Bay, Kimotsuki, Kagoshima, Japan, 31°17′N, 131°05′E, 2 Oct. 2012, 40 m; KAUM –I. 56772, 65.3 mm, KAUM –I. 56773, 65.7 mm, KAUM –I. 56989, 61.4 mm, KAUM –I. 56990, 62.7 mm, KAUM –I. 56991, 61.9 mm, KAUM –I. 56992, 57.0 mm, KAUM –I. 56993, 63.4 mm, KAUM –I. 56994, 57.9 mm, KAUM –I. 56995, 65.0 mm, KAUM –I. 56996, 60.7 mm, KAUM –I. 56997, 61.6 mm, KAUM –I. 56998, 61.5 mm, KAUM –I. 56999, 65.3 mm, KAUM –I. 57119, 68.1 mm, KAUM –I. 57120, 69.2 mm, KAUM –I. 57121, 58.4 mm, KAUM –I. 57122, 65.3 mm, KAUM –I. 57123, 59.5 mm, KAUM –I. 57124, 60.2 mm, off Shinchi, Uchinoura Bay, Kimotsuki, Kagoshima, Japan, 31°16ʹ55ʺN, 131°04ʹ49ʺE, 10 Oct. 2013, 25 m; MNHN 1959-0532, 1 of 2 specimens, 60.5 mm, Manila, Luzon, Philippines, 14°06′N, 120°58ʹ59ʺE; MNHN 1969-0062, 5 of 11, 69.2–72.1 mm, Chennai, Tamil Nadu, India, 13°04ʹ59ʺN, 80°28ʹ02ʺE, 5 Apr. 1966; USNM 242164, 5, 27.0– 31.8 mm, Ravao Island, Hall Sound, Papua New Guinea, 08°49ʹ41ʺS, 146°33ʹ00ʺE, 8 June 1979, 0–1 m; USNM 276471, 7, 29.0– 57.5 mm, Kilakarai, Gulf of Mannar, India, 20 Feb. 1964; USNM 276472, 11, 45.3–53.3 mm, Chennai, Tamil Nadu, India, 18 Mar. 1964; USNM 131108, 3, 31.7–34.2 mm, Varadero Bay, Mindoro, 22–23 July 1908. Encrasicholina heteroloba (111 specimens, 35.4–77.6 mm): ANSP 63369, 52.1 mm, Vigan, Ilocos Sur, Luzon, Philippines, 6 Feb. 1923; KAUM –I. 22950, 68.8 mm, mouth of Bang Pakong River, Chachoengsao, Thailand, 13°27′N, 100°57′E, 31 Aug. 2009; KAUM –I. 24120, 63.8 mm, Gulf of Thailand, Thailand, 20 Oct. 2009; KAUM –I. 56031, 56.2 mm, KAUM –I. 56032, 54.4 mm, off Iloilo, Panay Island, Philippines, 10°41′N, 122°35′E, 22 Aug. 2013; USNM 258488, 2, 43.9–45.5 mm, west shore of Kasa Island, Piru Bay, Ceram, Indonesia, 3°30′S, 128°13′E, 0–1 m, 4 Mar. 1974; USNM 327718, 20 of 438, 36.9–56.2 mm, Matalanim Harbor, Pohnpei Island, Caroline Islands, Micronesia, 0–2 m, 21–22 June 1971; USNM 327826, 20 of 527, 46.9–66.1 mm, Palau, 29 June to 3 July 1965; USNM 327830, 20 of 150, 43.0– 77.6 mm, Pacific Ocean, 13 June 1966; USNM 328591, 20 of 200, 37.7–67.9 mm, Pohnpei Island, Caroline Islands, Micronesia, 16 May 1966; USNM 330900, 20 of 50, 38.4–45.8 mm, Ponape Harbor, Pohnpei Island, Caroline Islands, Micronesia, 20 June 1971, 0–3 m; USNM 330915, 47.3 mm, Kusaie, Conquillo Harbor, Kosrae Island, Caroline Islands, Micronesia, 25 June 1971; USNM 404507, 2, 37.3–53.7 mm, Kilakarai, Gulf of Mannar, India, 20 Feb. 1964; USNM 404509, 46.6 mm, Chennai, Tamil Nadu, India, 18 Mar. 1964. Encrasicholina punctifer (118 specimens, 21.9–95.5 mm): ANSP 68308, holotype of E. punctifer , 29.9 mm, ANSP 68309, 12 paratypes of E. punctifer , 23.4–31.9 mm, Fare Bay, Huaheine Island, Society Islands, French Polynesia, 17 Apr. 1937; ANSP 82384, 10 of 19, 24.3–27.7 mm, Bora Bora Island, Society Islands, French Polynesia, 21 Apr. 1937; BMNH 1988.8.1.74–86, 11, 51.1–61.8 mm, Hainan Island, China, 22 Apr. 1988; KAUM –I. 6673, 52.7 mm, off Chiringa-jima island, Ibusuki, Kagoshima, Japan, 31°16′38″N, 130°40′18″E, 25 m, 3 Oct. 2007; KAUM –I. 7374, 53.5 mm, off Chiringa-jima island, Ibusuki, Kagoshima, Japan, 31°16′38″N, 130°40′18″E, 25 m, 28 Nov. 2007; KAUM –I. 7398, 55.2 mm, off Tsushiro, Uchinoura Bay, Koyama, Kimotsuki, Kagoshima, Japan, 31°17′N, 130°41′E, 40 m, 29 Oct. 2007,; KAUM –I. 10445, 95.5 mm, off Kaimon, Ibusuki, Kagoshima, Japan, 31°10′20″N, 130°32′56″E, 50 m, 25 June 2008; KAUM –I. 22921, 57.5 mm, mouth of Bang Pakong River, Chachoengsao, Thailand, 13°27′N, 100°57′E, 31 Aug. 2009; KAUM –I. 41056, 54.1 mm, KAUM –I. 41057, 53.2 mm, KAUM –I. 41058, 53.1 mm, east of Sakinoyama, Kataura, Kasasa, Minami-satsuma, Kagoshima, Japan, 31°25′44″N, 130°11′49″E, 27 June 2009, 27 m; MNHN 1959-0535, 53.7 mm, Manila, Luzon, Philippines, 14°06′N, 120°58.59′E; MNHN 1969-0057, 2, 54.1–55.3 mm, Kalient, Kerala, India, 8°30′00″N, 76°49′59″E; USNM 177742, holotype of Stolephorus buccaneeri , 51.0 mm, USNM 177743, 19 paratypes of S. buccaneeri , 42.2–54.5 mm, ca. 1.8 km west of Lehua Island off Niihau Island, Hawaian Islands, 15 Sept. 1958; USNM 177744, 8 paratypes of S. buccaneeri , 37.6–48.3 mm, taken from stomach of Euthynnus affinis captured from 1.6 km off Makua, Oahu, Hawaiian Islands, 10 Sept. 1958; USNM 204229, 3, 49.8–56.0 mm, Kalient, Kerala, India, 16 Aug. 1966; USNM 364070, 15, 54.5–65.4 mm, Fiji, June, 1972; USNM 404508, 28.1 mm, Kilakarai, Gulf of Mannar, India, 20 Feb. 1964; USNM 417167, 26 of 111, 21.9–70.2 mm, east of Agrihan Island, Northern Mariana Islands, 19°02′00″N, 148°25′00″E, 7 Nov. 1971, 50 m. Encrasicholina purepurea (11 specimens, 35.0– 58.9 mm): ANSP 23329, 2 syntypes of Stolephorus purpureus , 48.3–50.7 mm, Hawaiian Islands; ANSP 65478, 53.4 mm, ANSP 86386, 58.8–58.9 mm, Honolulu, Oahu Island, Hawaiian Islands, 31 Oct. 1923; MNHN 1975-1113, 6 of 12, 35.0– 51.2 mm, north of Oahu Island, Hawaiian Islands, 21°49′59″N, 158°00′00″W, 100 m, 26 Apr. 1973.

Figures

FIGURE 1. Holotype of Encrasicholina macrocephala n. sp. MNHN 2014 - 0152, 44.6 mm standard length, Djibouti.

FIGURE 2. Relationships of (A) ratio of head length to standard length vs. standard length, (B) ratio of D – P 1 length to head length vs. standard length, (C) ratio of upper-jaw length to standard length vs. standard length, and (D) ratio of lower-jaw length to standard length vs. standard length in Encrasicholina macrocephala n. sp. [open circles (open star = holotype)] and E. devisi [closed triangles (closed star = holotype)].

Tables

TABLE 2. Morphometrics of specimens of Encrasicholina macrocephala n. sp. and E. devisi.

	Encrasicholina macrocephala n. sp.	Encrasicholina devisi
Standard length (SL; mm) As % SL	Holotype Paratypes Djibouti Djibouti and Oman MNHN 2014-0152 n = 16 Means 44.6 42.3–55.7	Holotype Non-types Australia Indo-West Pacific AMS IB. 609 n = 93 Means 44.0 27.0–78.4
Head length (HL) Body depth Pre-dorsal-fin length	31.3 29.5–31.7 30.4 16.4 14.0–16.4 14.9 54.9 51.1–55.5 53.5	broken 25.4–28.9 26.7 17.7 11.3–19.5 16.1 53.0 49.1–55.4 52.2
Snout tip to pectoral-fin insertion Snout tip to pelvic-fin insertion Snout tip to anal-fin origin	31.5 30.2–32.6 31.4 49.6 45.8–51.3 49.1 66.9 64.5–70.9 67.3	28.0 25.6–30.8 27.7 47.5 40.4–50.2 46.1 64.5 59.3–69.0 64.3
Dorsal-fin base length Anal-fin base length Caudal-peduncle length	11.8 10.7–12.7 11.8 17.0 13.9–17.2 15.4 17.4 16.9–20.1 18.2	10.9 8.6–14.6 11.8 broken 13.6–19.6 16.6 18.2 16.0–24.1 19.9
Caudal-peduncle depth Pectoral-fin length Pelvic-fin length	7.9 7.6–8.7 7.9 broken 14.8–16.2 15.5 9.2 8.5–10.4 9.4	8.4 7.0–10.0 8.3 broken 12.5–15.8 14.3 broken 7.7–10.2 8.9
Interorbital width Upper-jaw length Mandibular length	6.0 5.8–6.5 6.2 21.3 21.6–23.5 22.2 19.8 19.5–21.2 20.2	5.2 4.7–7.2 5.9 broken 14.6–21.3 18.9 18.2 14.2–19.5 17.5
Supramaxilla end to maxilla end 1st unbranched dorsal-fin ray length 2nd unbranched dorsal-fin ray length	1.3 1.7–2.6 2.0 1.0 0.6–1.3 0.9 broken 4.6–7.3 6.0	broken 1.0–2.6 1.9 0.9 0.4–1.7 1.0 broken 5.3–8.7 6.7
3rd dorsal-fin ray length 1st unbranched anal-fin ray length 2nd unbranched anal-fin ray length	broken 14.4–18.2 16.8 1.0 0.5–1.0 0.8 broken 3.0–4.5 3.8	broken 12.4–19.0 15.6 0.9 0.3–1.7 0.9 broken 2.3–5.1 3.9
3rd anal-fin ray length 1st pectoral-fin ray length 1st pelvic-fin ray length	broken 9.8–12.1 11.1 broken 15.2–16.2 15.6 broken 8.1–10.4 9.2	broken 9.3–14.8 10.7 broken 12.7–15.8 14.4 broken 7.6–10.2 8.6
As % HL Orbit diameter Eye diameter	28.9 26.9–31.9 29.3 21.9 21.9–25.3 22.9	– 25.9–32.7 30.1 – 19.6–27.5 24.7
Snout length D–P1 D–P2	18.0 16.8–18.5 17.7 86.3 83.2–95.2 89.8 53.6 48.0–55.2 52.8	– 14.9–19.3 17.6 – 97.5–126.1 111.0 – 48.1–79.3 65.5
D–A P1–P2 P2–A	62.9 59.3–71.8 66.1 52.5 51.4–70.1 61.0 57.2 53.6–62.6 59.2	– 62.9–85.9 76.2 – 57.4–84.6 72.4 – 52.3–82.2 67.8
Postorbital length Width of ventral urohyal	51.4 51.1–55.6 52.5 1.5 1.0–4.8 3.0	– 48.8–56.3 52.3 – 0.1–4.1 2.3