Discordipinna griessingeri Hoese & Fourmanoir, 1978

Chou, Li-Chin, Jiang, Guo-Chen & Shen, Kang-Ning, 2024, A newly recorded gobiid genus, Discordipinna (Teleostei: Gobiidae), from northeastern Taiwan, Zootaxa 5550 (1), pp. 41-45 : 42-44

Discordipinna griessingeri Hoese & Fourmanoir, 1978

(New Chinese name: DZ來ĸľēüṻ)

( Figs. 1–2 )

Discordipinna griessingeri Hoese & Fourmanoir, 1978: 21 (El Himeira, Egypt, Gulf of Aqaba, Red Sea).

Discordipinna griessingeri, Hagiwara et al., 1996:2 .

Discordipinna griessingeri, Akihito et al., 2002:1250 .

Discordipinna griessingeri, Suzuki & Shibukawa, 2004: 443 .

Discordipinna griessingeri, Motomura et al. in Motomura & Matsuura, 2010: 208.

Discordipinna griessingeri, Chen, Suzuki & Shao, 2012: 275 .

Materials examined. Taiwan. NTOUP-2021-06-205 , 1 specimen, 25.3 mm SL, 20 m depth, Longdong Bay , New Taipei City, Taiwan, ROC, coll. I-S. Chen et al., 23 June, 2021. The Philippines. NTOUP-2011-01-001 , 3 specimens, 13.3–13.7 mm SL, Mactan , Cebu Island, the Philippines, coll. A. Chen et al., 8 Nov., 2009 .

Diagnosis. This species can be well distinguished from congeners by the unique combination of the following features: (1) fins: first dorsal fin rays V; pectoral fin rays 17–20 (modally 18); and first dorsal fin with longest anterior two rays in male and fin membrane deeply indented between first two dorsal spines; (2) squamation: longitudinal scale rows 22–25; transverse scale rows usually 6–7 and predorsal naked; (3) dorsal pterygiophore formulae 3/41001/8; 10 + 16 = 26 vertebrae; (4) head lateral-line system: reduced, longitudinal pattern of infraorbital papilla and anterior oculoscapular canal present (with pore λ singular on middle of interorbital region, pore κ singular on posterior interorbital region and lateral section as pores α, β, and ρ) but lacking both preopercular and posterior oculoscapular canals; and (5) coloration pattern: body creamy yellow with wide longitudinal brown band on ventral half; head with many round brownish black spots; first dorsal fin orange red; pectoral fin orange with an oblique translucent band; second dorsal and caudal fins with several deep brown blotches each having a central black spot.

Redescription. Body proportions are described in Table 1 . Body subcylindrical anteriorly, compressed posteriorly. Head moderately large, snout somewhat pointed in lateral view. Eye rather large, dorsolateral. Mouth rather oblique, about 45 degrees to horizontal line, with rear margin extending to vertical of anterior margin of pupil in both sexes. Lower lip anteriormost. Both jaws with 2–4 rows of tapered, sharp teeth, and outer rows enlarged. Anterior nasal pore a short tube, and posterior nasal pore a round opening. Gill-opening restricted, extending forward ventrally somewhat beyond a vertical at upper edge of the opening. Dorsal pterygiophore formula: 3/122101/9. 10 + 16 = 26 vertebrae.

Fins.— First dorsal fin rays V; second dorsal fin rays I/8; anal fin rays I/8; pectoral fin rays 17–20 (modally 18). First dorsal fin with longest anterior two rays in male, and fin membrane deeply indented between first two dorsal spines; its rear tip at least reaching midline of second dorsal fin base or beyond rear base of second dorsal when adpressed. Origin of anal fin inserted just below origin of first branched ray of second dorsal fin. Rear tips of second dorsal and anal fins when adpressed, just reaching procurrent rays of caudal fin. Pectoral fin rather large and oblong, with rear margin extending beyond vertical of origin of anal fin. Pelvic fin long with large frenum and membrane around its spinous rays bilobed. Rear tip of pelvic fin extending beyond vertical through anus. Caudal fin large and elliptical, with its fin length longer than head length.

Scales.— Body with rather large ctenoid scales; belly scales cycloid; longitudinal scale rows 22–25; transverse scale rows 6–7; predorsal scale 0. Prepelvic and belly with cycloid scales. Head and predorsal region entirely naked.

Head lateral-line system. Canals: Anterior oculoscapular canal extension with anteriorly paired terminal pores σ slightly behind posterior nasal pore. Pore λ singular in middle of interorbital region; pore κ singular in rear dorsal vertical of orbit beyond pore λ. Paired pores ω behind eyes on nape. Lateral extension of anterior oculoscapular canal behind orbit as pore α, followed by middle pore β and terminal pore ρ. Lacking both preopercular and posterior oculoscapular canals.

Sensory Papillae: Cheek with loosely arranged, longitudinal infraorbital papillae. Row a very short with four papillae, not extending vertically through middle of eye. Row b short, merely with three papillae. Rows c and d longer with more papillae in row c, and row c extending posteriorly to vertical through poreα. Opercle with three main rows as rows os, ot, and oi, with both rows ot and oi slightly separated. Row f as paired papillae.

Coloration in fresh. Body creamy white to light yellow background with wide longitudinal bright orange-red to brown band on ventral half and upper half with 3–4 longitudinal rows of very thin orange stripes. Head with many round brownish black spots; eyes surrounded by seven round brownish black spots just radiating off pupil. Nape with several round brownish black spots on anterior half.

First dorsal fin bright orange-red with a thin brown rear margin. Pectoral fin bright orange with an oblique translucent band. Second dorsal and caudal fins with several deep brown blotches, including a central blackish brown spot.

Caudal fin bright orange background with middle wide longitudinal creamy white band. Anal fin translucent with distal narrow bright orange band. Pelvic fin pale white with anterior orange-red region.

Distribution. This species is widely distributed from the Red Sea and the Indian Ocean to the tropical West Pacific region. It is present in countries such as the Philippines, Malaysia, Indonesia, Japan, specifically from the Ryukyu Islands to the Wakayama Prefecture in the middle of the main island ( Hagiwara et al., 1996; Akihito et al., 2002; Suzuki & Shibukawa, 2004). This study is the first formal record of its presence in Taiwanese waters.

Figures

FIGURE 1. Discordipinna griessingeri Hoese & Fourmanoir, 1978, NTOUP-2021-06-205, 25.3 mm SL, female, Longdong Bay, New Taipei City, ROC.

FIGURE 2. Discordipinna griessingeri Hoese & Fourmanoir, 1978, NTOUP-2011-01-001, 13.7 mm SL, male, Mactan, Cebu Island, the Philippines.

Tables

TABLE 1. The morphometry of Discordipinna griessingeri Hoese & Fourmanoir, 1978 from Taiwan

Standard length (mm)	25.3
% inSL
Head length	20.9%
Predorsal length	26.1%
Snout to 2nd dorsal fin origin	61.2%
Snout to anal fin origin	63.4%
Snout to anus	59.0%
Prepelvic length	28.4%
Caudel peduncle length	20.1%
Caudal peduncle depth	11.9%
First dorsal fin base	19.4%
First dorsal fin length	51.1%
Second dorsal fin base	23.9%
Anal fin base	20.9%
Caudal fin length	41.0%
Pectoral fin length	43.3%
Pelvic fin length	31.3%
Body depth of pelvic fin origin	17.9%
Body depth of anal fin origin	15.3%
Body width of anal fin origin	15.7%
Pelvic fin origin to anus	33.6%
% inHL
Snout length	33.9%
Eye diameter	39.3%
Postorbital length	44.6%
Cheek depth	35.7%
Head width in upper gill-opening	67.9%
Bony interorbital width	7.5%
Lower jaw length	47.9%