Symphurus multimaculatus, Lee, Mao-Ying, Munroe, Thomas A. & Chen, Hong-Ming, 2009

Lee, Mao-Ying, Munroe, Thomas A. & Chen, Hong-Ming, 2009, A new species of tonguefish (Pleuronectiformes: Cynoglossidae) from Taiwanese waters, Zootaxa 2203, pp. 49-58 : 51-55

Symphurus multimaculatus , new species

( Figs. 1–2 , Tables 1–2 )

Pepperdot Tonguefish

Holotype. ASIZP 67634, female, 93.5 mm SL; Nanfang-Ao fish port in landings of commercial bottom trawler fishing off northeastern coast of Taiwan; M.- Y. Lee; 6 Jan 2007.

Paratypes. (all collected from commercial fish catches of bottom trawlers landed at fish ports). ASIZP 67647, female, 79.6 mm SL; off northeastern coast of Taiwan, Da-shi fish port; M.- Y. Lee; 22 Jun 2007. ASIZP 67648, female, 75.0 mm SL; off northeastern coast of Taiwan, Da-shi fish port; M.- Y. Lee; 22 Jun 2007. ASIZP 67654, male, 64.7 mm SL; off southwestern coast of Taiwan, Dong-gang fish port; M.- Y. Lee; 4 Jul 2007. ASIZP 67655, male, 69.5 mm SL; off southwestern coast of Taiwan, Dong-gang fish port; M.- Y. Lee; 4 Jul 2007. USNM 394605, male, 90.6 mm SL; off southwestern coast of Taiwan, Dong-gang fish port; H.-C. Ho; 13 Nov 2007. USNM 394606, male, 78.5 mm SL; off southwestern coast of Taiwan, Dong-gang fish port; H.-C. Ho; 13 Nov 2007.

Additional non-type specimens examined. (all collected from commercial fish catches of bottom trawlers landed at fish ports). ASIZP 67641, female, 103.8 mm SL; off northeastern coast of Taiwan, Da-shi fish port; M.- Y. Lee; 9 Mar 2007. ASIZP 67642, male, 92.2 mm SL; off northeastern coast of Taiwan, Nanfang-ao fish port; M.- Y. Lee; 28 Feb 2007.

Diagnosis. Symphurus multimaculatus is distinguished from all congeners by the combination of: 1–2–2– 2–2 ID pattern, 14 caudal-fin rays, 9 abdominal vertebrae, 50–51 total vertebrae, 5 hypurals, 92–94 dorsal-fin rays, 79–82 anal-fin rays, 102–108 longitudinal scales, 45–48 scales in a transverse row, a small eye (9.1– 10.1% HL), deep body (28.6–35.1% SL), and blind-side pigmentation featuring conspicuous, irregular, blackish-brown speckles especially conspicuous overlying pterygiophore regions of the dorsal and anal fins.

Description. Symphurus multimaculatus is a medium-sized species, reaching sizes to 103.8 mm SL. Meristic characters are summarized in Table 1 . Predominant ID pattern 1–2–2–2–2 (9/ 9 specimens). Caudalfin rays 14 (two specimens abnormalities). Dorsal-fin rays 92–94. Anal-fin rays 79–82. Pelvic-fin rays 4. Total vertebrae 50–51; abdominal vertebrae 9(3 + 6). Hypurals 5. Longitudinal scale rows 102–108. Scale rows on head posterior to lower orbit 21–24. Transverse scales 45–48.

Longitudinal scales

102* 103 104 105 106 107 108 Frequency 1 1 3 2 1 - 1

a Includes specimen with two sites of fused caudal vertebrae indicated by multiple neural and haemal spines in the first fusion, and by two haemal spines in the second site of fusion.

Proportions of morphometric features are presented in Table 2 . Body relatively deep; maximum depth in anterior one-third of body usually at point between anus and fourth anal-fin ray, with moderate posterior taper from anus to posterior body margin. Preanal length smaller than body depth. Head moderately short and wide; head width slightly shorter than body depth, and much greater than head length (HW/HL= 1.26–1.50, x = 1.33). Upper head lobe wider than lower head lobe (UHL/LHL= 1.34–1.67, x = 1.48); slightly longer than postorbital length. Lower lobe of ocular-side opercle wider than upper opercular lobe; posterior margin of lower lobe projecting slightly beyond posterior margin of upper opercular lobe. Snout moderately long, slightly round to obliquely blunt anteriorly, its length greater than eye diameter (SNL/ED= 1.54–1.90, x =1.74). Dermal papillae present, but not well developed, on blind-side snout. Ocular-side anterior nostril tubular and short, usually not reaching anterior margin of lower eye when depressed posteriorly. Ocular-side posterior nostril a small, rounded tube located on snout just anterior to interorbital space. Blind-side anterior nostril tubular and slightly elongate, easily distinguishable from dermal papillae; blind-side posterior nostril a shorter and wider posteriorly-directed tube situated posterior to vertical at posterior margin of jaws. Jaws long and slightly arched; upper jaw length longer than snout length; posterior margin of upper jaw usually extending to point between verticals through anterior margin of pupil and midpoint of lower eye. Ocular-side lower jaw without fleshy ridge. Cheek depth slightly greater than snout length. Eyes moderately large and oval, separated by three to four rows of small ctenoid scales in narrow interorbital space. Eyes usually equal in position, or upper eye slightly in advance of lower eye. Pupillary operculum absent. Dorsal-fin origin located at point between verticals through anterior margin of pupil and anterior margin of dorsal eye; predorsal length moderately short. Anteriormost dorsal-fin rays slightly shorter than more posterior fin rays. Scales absent on both sides of dorsal- and anal-fin rays. Pelvic fin moderately long; longest pelvic-fin ray, when extended posteriorly, usually reaching base of first anal-fin ray. Posteriormost pelvic-fin ray connected to anal fin by delicate membrane. Caudal fin relatively long, with several rows of ctenoid scales on base of fin. Scales numerous, strongly ctenoid on both sides of body.

Holotype and other specimens

Character Holotype n Range Mean±SD Teeth present and recurved slightly inwards on all jaws, but better developed on blind-side jaws. Ocularside premaxilla and dentary with single row of sharply pointed, well-developed teeth. Blind-side premaxilla with three to four rows of sharp, recurved teeth. Blind-side lower jaw with three to five rows of welldeveloped teeth.

Coloration ( Figs.1–2 ). Freshly-caught specimens. Background body coloration differing slightly between adults and juveniles. Ocular-side background pigmentation of adults ( Fig. 1 ) generally reddishbrown to dark-brown; juveniles ( Fig. 2 ) with bluish-black to purple background coloration. General background coloration more intense on body areas overlying dorsal and anal pterygiophores. Adults and juveniles usually with 5–7 distinct, wide (covering 4–8 scales), complete and incomplete dark blackish-brown crossbands on body (crossbands faded and indistinct in some specimens); crossbands not continued onto dorsal and anal fins. Anteriormost crossband on body region between opercle and vertical through anus; successive crossbands on mid-body region to caudal-fin base. External surface of abdominal area sometimes bluish-black, but usually with same general coloration as that of ocular-side body (because darker peritoneal pigment obscured by abdominal wall and not visible externally). Background coloration of ocular-side head generally similar to that on body. Ocular-side snout light brown. Outer surface of ocular-side opercle blackish-brown; inner surface of ocular-side opercle with small blackish-brown or black chromatophores. Ocular-side lips and chin region dark brown, margins of lips pigmented with small black chromatophores. Ocular-side anterior nostril blackish-brown. Upper aspects of eyes and eye sockets light blue; pupils bluishblack.

Blind side generally white to light yellow with numerous, small, blackish-brown pepper-dots irregularly distributed over blind-side body, but usually most dense and conspicuous on body regions overlying pterygiophores of dorsal and anal fins. A cluster of blackish-brown speckles usually surrounding anus. External surface of abdominal region whitish in adults (because peritoneal coloration difficult to observe through thick abdominal wall), but lightly bluish-black in juveniles where dark peritoneum shows through abdominal wall. Outer surface of blind-side opercle bluish-black. Inner surface of blind-side opercle with numerous, small, blackish-brown chromatophores.

trawler off northeastern Taiwan. A. Ocular-side pigmentation of freshly caught juvenile female. B. Blind-side coloration of same specimen.

Fin rays of dorsal, anal, and pelvic fins uniformly reddish-brown or bluish-brown; basal regions of fin rays and membranes covering fin rays grayish-blue. Numerous, small, dense, and nearly spherical spots covering entire fin membranes on both sides of fins, giving fin membranes a reddish-brown or bluish-brown color. Basal margins of fin rays on blind side, and associated fin membranes, reddish-brown to grayish-blue.

Coloration of recently preserved specimens similar to that of freshly-caught fishes, except that coloration of fin rays (on both sides) of some preserved specimens faded to nearly transparent.

Size and sexual maturity. Nine specimens range in size from 64.7–103.8 mm SL. Four of these are females; two (75.0– 79.6 mm SL) are immature showing little elongation of the ovaries, while two others (93.5–103.8 mm SL) are non-gravid, mature females with elongate ovaries, but without any ova evident. Males (n = 5, 64.7–92.2 mm SL) attain similar sizes to those of females.

Distribution. Symphurus multimaculatus is currently known only from commercial fish catches taken on the continental shelf and/or upper continental slope off Taiwan. All nine specimens examined in this study were collected by trawlers operating in deep waters near Da-shi and Nanfang-Ao off northeastern Taiwan, and off Dong-gang, southwestern Taiwan. Though specific depth of capture information is lacking for these specimens, we conclude that S. multimaculatus is a deepwater tonguefish that occurs on the continental shelf and/or continental slope based on the evidence that all nine specimens were retrieved from catches landed at fishing ports that also contained S. orientalis and other deep-sea fishes known to occur at depths of about 300– 400 m. Additionally, S. multimaculatus also features a black peritoneum, a pigmentation feature characteristic of other deepwater (> 200 m) species of Symphurus (Munroe 1998; Munroe 2006; Munroe and Amaoka 1998; Krabbenhoft and Munroe 2003; Munroe and Hashimoto 2008; Lee et al. 2009).

Symphurus multimaculatus apparently is a rarely-caught species. Only nine specimens were retrieved from numerous port samples that were sorted, and which also contained several hundred specimens of other species of Symphurus . Furthermore, research vessels conducting bioinventories of deep waters around Taiwan during the past several years (K.-T. Shao, unpubl. data) also have not collected any specimens of this species during these investigations. Further collections by research vessels with capabilities for discrete sampling are needed to gain better understanding of the ecology, abundance and life history of this species.

Etymology. The name multimaculatus is derived from the Latin, multi meaning many, and maculatus, meaning spots, in reference to the numerous blackish-brown speckles on the blind-side body and fins of this species.

Remarks. In S. multimaculatus , one of nine specimens has two sites of fused caudal vertebrae as evidenced by the presence of multiple neural and/or haemal spines on a centrum, which also has a different size and shape compared with other centra. The first site of fused vertebrae is located at caudal vertebrae No. 27, which has double neural and haemal spines. The second site of fused vertebrae is located at vertebrae No. 32, which has double haemal spines. Presence of multiple neural and haemal spines on caudal vertebra indicates that some unknown number of vertebrae either failed to develop or have fused during development. Based on previous studies ( Munroe & Mahadeva 1989; Munroe & Hashimoto 2008), estimating only two vertebrae involved in such fusions resulted in vertebral counts that were within the range of this count recorded for specimens without fused vertebrae. In the case of S. multimaculatus , each fusion, when interpreted as involving only two vertebrae, results in a vertebral count of 50, which is within the range recorded for the other specimens of S. multimaculatus without fused vertebrae ( Table 1 ).

Two of the nine specimens also have anomalies associated with their caudal-fin rays as reflected in abnormal shapes of their hypurals and/or associated skeletal elements. For example, one specimen has two sites of fused caudal-fin rays; one site is located on caudal-fin rays supported by the parhypural and hypural– 1, and the other site involves caudal-fin rays associated with hypural–1. Normal specimens usually have four fin-rays associated with the parhypural and hypural–1 and three fin-rays associated with hypural–1 and hypural–2. In this specimen, the fin ray located between the parhypural and hypural–1 is slender and is fused with the last fin-ray supported by the parhypural, which results in only three fin rays being located between the parhypural and hypural–1. The fin ray associated with hypural–1 is also fused with the fin ray on hypural– 2 resulting in a single, wider fin ray, and this fusion consequently results in only two fin rays being located between hypurals–1 and –2. The other specimen with anomalous caudal-fin rays has the bases of the first and second caudal-fin rays, which are supported by the parhypural, fused together. Also in this specimen, the epural and proximal radial of the posteriormost dorsal fin are fused. This anomaly results in a fusion of the bases of the first four caudal-fin rays with their respective rays radiating distally.

Figures

FIGURE 1. Symphurus multimaculatus, new species, holotype (ASIZP 67634, 93.5 mm SL) taken by commercial trawler off northeastern Taiwan. A. Ocular-side pigmentation of freshly-caught adult female. B. Blind-side coloration of same specimen.

FIGURE 2. Symphurus multimaculatus, new species, paratype (ASIZP 67648, 75.0 mm SL) taken by commercial

Tables

TABLE 1. Meristic features for Symphurus multimaculatus taken off Taiwan. Counts for holotype (ASIZP 67634) indicated by asterisk (*). Footnote refers to specimen with anomalous vertebrae (vertebral count estimated, See Methods and Remarks); ANO = Abnomality.

	ID Pattern 1–2–2–2–2*	Caudal-fin rays ANO 14*	Abdominal Vertebrae 9*	Total vertebrae 50* 51
Frequency	9 Dorsal-fin rays 92 93	2 7 94*	9 Anal-fin rays 79 80	5a 4 81* 82
Frequency	1 3 Head Scales 21 22*	5 23 24	1 2 Transverse scale 45 46	2 4 47* 48
Frequency	2 4	2 1	1 3	3 2

TABLE 2. Morphometrics for holotype (ASIZP 67634), six paratypes and two non-type specimens of Symphurus multimaculatus taken off Taiwan. SL in mm; characters 2 – 15 in % of SL; 16 – 23 in % of HL.

1. Standard length	93.5	9 64.7–103.8	83.04±12.74
2. Body depth	32.6	9 28.6–35.1	31.16±2.00
3. Trunk length	82.2	9 79.3–85.2	82.47±1.83
4. Predorsal length	3.1	9 3.1–3.9	3.39±0.28
5. Preanal length	24.2	9 22.4–25.3	23.80±1.00
6. Dorsal-fin length	96.7	9 95.7–96.9	96.42±0.43
7. Anal-fin length	75.8	9 74.0–77.6	76.17±1.11
8. Pelvic-fin length	5.7	9 5.7–7.2	6.34±0.54
9. Pelvic to anal length	3.0	9 2.2–4.4	3.10±0.71
10. Caudal-fin length	11.8	9 10.2–13.9	12.00±1.23
11. Head length	20.3	9 18.3–20.8	19.89±0.76
12. Head width	27.2	9 24.5–30.2	26.54±2.07
13. Postorbital length	14.1	9 12.6–14.5	13.88±0.60
14. Upper head lobe width	16.1	9 14.4–18.2	15.83±1.16
15. Lower head lobe width	11.0	9 9.2–12.6	10.76±1.02
16. Predorsal length	16.3	9 15.2–19.1	17.14±1.41
17. Postorbital length	69.5	9 67.8–71.7	69.91±1.34
18. Snout length	17.4	9 15.6–18.8	17.01±1.06
19. Upper jaw length	23.2	9 22.2–25.1	23.48±1.08
20. Eye diameter	9.7	9 9.1–10.1	9.78±0.30
21. Chin depth	15.8	9 15.8–22.1	18.68±2.08
22. Lower opercular lobe	31.6	9 29.6–37.6	31.86±2.65
23. Upper opercular lobe	22.6	9 21.1–30.3	23.82±3.05
24. HW/HL	1.34	9 1.26–1.50	1.33±0.080
25. Pupil/Eye diameter	0.68	9 0.61–0.72	0.68±0.039