Pseudanthias tequila, Gill & Tea & Senou, 2017

Gill, Anthony C., Tea, Yi-Kai & Senou, Hiroshi, 2017, Pseudanthias tequila, a new species of anthiadine serranid from the Ogasawara and Mariana Islands, Zootaxa 4341 (1), pp. 67-76 : 68-75

Pseudanthias tequila new species

New standard Japanese name: Bonin-hanadai English common name: Cave anthias Figures 1–7 , Table 1

Pseudanthias randalli (non Lubbock & Allen, 1978); Myers & Shephard, 1980: 316 (Blue Hole, Orote Peninsula, Guam). Pseudanthias sp.; Myers, 1988: 140 (Guam).

Pseudanthias sp. 3; Michael, 1998: 576 (colour photo; Guam).

Pseudanthias sp. B; Myers 1999: 109, pl. 35 G (colour photo; Guam).

Pseudanthias flavicauda [non Randall & Pyle, 2001]; Myers & Donaldson, 2003: 616 (list, Marianas Islands). Pseudanthias cf randalli ; Kuiter, 2004: 61, unnumbered colour figs A and B (colour photos; Palau, Saipan and Guam). Pseudanthias cf flavicauda ; Kuiter & Debelius, 2006: 298 (colour photo; Micronesia).

Holotype. KPM-NI 3759 , 59.3 mm SL, male, Japan, Ogasawara Islands , Chichi-jima Islands, Ototo-jima Island, 40 m, collected by O. Morishita, 16 March 1997.

Paratype. KPM-NI 3758 , 31.5 mm SL, female, collected with holotype.

Diagnosis. The following combination of characters distinguishes Pseudanthias tequila from congeners: dorsal rays X,16; anal rays III,7; pectoral rays 18; third dorsal spine prolonged in males; third segmented anal-fin ray longest; lateral-line scales 46–47; no auxiliary scales on body; interopercle and subopercle with distinct serrations in adults; males in life with upper body beneath anterior part of dorsal fin purple to pink with orange-red stripe, dorsal fin greenish yellow anteriorly, posteriorly red with blue basal area, anterior part of anal fin red, and pelvic fins bright yellow.

Description. Dorsal rays X,16, all segmented rays branched; each dorsal fin spine with fleshy pennant extending from tip, this best developed on longest (third) spine; anal rays III,7, all segmented rays branched; pectoral rays 18/18, all rays branched except upper 2/2 and lower 1/1 (2/2); pelvic rays 1,5; principal caudal rays 9 + 8; branched caudal-fin rays 7 + 6; upper procurrent caudal-fin rays 8 (9); lower procurrent caudal rays 8 (9); lateral-line scales too damaged (and regrown) on left side of holotype, 46 on right side (49/48); scales above lateral-line to origin of dorsal fin 5/5; scales above lateral-line to base of fifth dorsal spine 4/4 (3/4); scales below lateral line to origin of anal fin 18/19 (20/19); circumpeduncular scales not determinable in holotype (24); gill rakers 10 + 23 (8 + 21); branchiostegal rays 7; pseudobranch filaments 16 (10).

Vertebrae 10 + 16; supraneurals 3 (posterior two closely applied in paratype, though still separate); predorsal formula 0/0+0/2/1+1; main shaft (proximal component) of first dorsal pterygiophore roughly perpendicular to long axis of body; no trisegmental pterygiophores associated with dorsal and anal fins; ribs present on vertebrae 3 through 10; epineurals present on vertebrae 1 through 12; paired parapophyses present on first caudal vertebra (see Baldwin 1990: fig. 21B); parhypural and hypurals autogenous; well-developed hypurapophysis on parhypural; epurals 3; single uroneural (posterior uroneural absent); ventral tip of cleithrum with well-developed posteroventral process ( Figure 3 ).

Morphometric values are summarised in Table 1.

KPM-NI 3759 KPM-NI 3758 Holotype Paratype Mouth large, slightly oblique, posterior margin of maxilla reaching to vertical through posterior edge of pupil; mouth terminal, lower jaw projecting slightly; premaxilla with an enlarged recurved canine anterolaterally, a band of small conical teeth about five rows wide at symphysis reducing to two rows on sides of jaw, with the outer row teeth larger and slightly curved, and the three or four teeth nearest symphysis enlarged and caniniform, lying almost flat against roof of mouth; dentary with an enlarged recurved canine at symphysis, followed by a band of small conical teeth about three or four rows wide; sides of lower jaw with single row of slightly curved, conical teeth, with one or two teeth on middle of jaw greatly enlarged and caniniform; vomer with a triangular patch of small conical teeth, three rows wide in midline; palatine with a narrow band of small conical teeth, two rows wide at widest point; ectopterygoid, mesopterygoid and tongue edentate.

Opercle with 3 flat spines, middle spine longest, upper spine mostly concealed by scales; preopercle with 20 (15) fine serrations on vertical portion, 2 (1) enlarged serrations at angle, and 4 (0) weak serrations on ventral portion; interopercle with 5 (2) relatively large serrations; subopercle with 6 (2) relatively large serrations; posttemporal with 4 (3) fine serrations; supracleithrum with 2 fine serrations. Anterior nostril positioned at middle of snout, tubular with small flap on posterior rim, flap almost reaching posterior nostril when laid back; posterior nostril at mid-upper, anterior border of orbit, covered by thin, narrow membrane anteriorly. No papillae on posterior rim of orbit. Snout of holotype slightly hypertrophied with papillae at symphysis.

Scales ctenoid with peripheral cteni ( Roberts 1993); lateral line broadly arched over pectoral fin following body contour to caudal-fin base; head scaled, including dentary, maxilla, snout, and infraorbitals, no scales on lips; no auxiliary scales on body, a few auxiliary scales on cheeks and operculum; low scaly sheath on soft dorsal and anal fins, with indistinct small scales present between segmented rays; caudal fin with scaly basal sheath, with small scales extending over almost all of fin, except for fin tips and posterior part of membranes of middle rays; pectoral fins with basal, wedge-shaped sheath of small scales.

Colour of males in life (based on colour photos of holotype when freshly dead, and of live individuals in the Ogasawara and Mariana Islands; Figures 1 , 4A & B ): head and body purple to pink; bright purple stripe extending from anterior edge of eye around ventral part of orbit to lower part of pectoral-fin base; snout, interorbital area and area above stripe orange to orange-red; indistinct purple stripe sometimes present from behind middle of eye to upper part of pectoral fin base; iris orange to purple, bright yellow around pupil; upper part of body with broad orange-red stripe extending from behind head to caudal peduncle; similar orange-red stripe extending from pectoral-fin base along midside to caudal peduncle; scales on nape and body often dark basally; dorsal fin greenish yellow in front of eighth to tenth spine, bright red posteriorly, with bright blue base and distal margin; anal fin bright red anteriorly, with bright blue wedge extending from near base of first segmented ray to posterior part of fin, distal margin of red region narrowly edged with bright blue; caudal fin variable (probably mood induced), either bright yellow, greenish yellow with purple base, or solid purple, the upper and lower edges of fin bright blue; pelvic fins bright yellow, with spine dusky red to bright orange-red; pectoral fins orangish hyaline.

Colour of females in life (based on colour photos of paratype when freshly dead, and of live individuals in the Ogasawara and Mariana Islands; Figures 2 , 5 & 6 ): head and body purple to orange-pink; snout, lips and upper part of head yellow-grey to bright yellow; iris yellow with submarginal purple ring around pupil; scales of nape and body purplish grey or brown to bright red basally; caudal peduncle yellow; dorsal fin greenish to yellowish hyaline anteriorly, reddish to greenish hyaline posteriorly, with bright purple-blue distal margin; anal fin red to yellow anteriorly, becoming reddish hyaline posteriorly, with bright purple-blue leading edge of fin; caudal fin bright yellow, yellowish hyaline distally on central rays, with upper and lower edges of fin narrowly bright purple-blue; pelvic fins yellowish hyaline, bright purple-blue on leading edge; pectoral fins pinkish to orangish hyaline.

Colour in preservative: both sexes generally pale tan, lighter ventrally; basal markings on nape and body scales remain, becoming greyish brown; other markings on body and fins obsolete.

Habitat and distribution. Pseudanthias tequila is described on the basis of two specimens from Ototo-jima, Chichi-jima Islands, Ogasawara Islands, Japan. We also record it from Guam, Saipan and Tinian in the Mariana Islands on the basis of photographs ( Figure 7 ). Kuiter’s (2004) photograph of an individual of “ Pseudanthias cf randalli ”, stated to be from Palau, is referable to P. tequila . However, R.F. Myers (pers. comm.) advised us that the photograph, by Hiroyuki Kimura, is actually from Saipan. Other photographs from Palau are referrable to the closely related P. randalli ( Lubbock & Allen, 1978) . The original description of P. randalli also included paratypes from Palau. Pseudanthias tequila appears to be mostly found in caves on reef slopes in 40–60 m, earning it the popular name of “cave anthias”. In Saipan and Tinian, however, it occurs in the open on reef slopes dominated by Halimeda and Caulerpa algae ( Figures 4B & 6 ).

Comparisons. Pseudanthias tequila most closely resembles P. randalli ( Lubbock & Allen, 1978) from the West Pacific, P. pulcherrimus Heemstra & Randall (1986) from the Indian Ocean, P. flavicauda Randall & Pyle (2001) from the south-west Pacific, and P. oumati Williams, Delrieu-Trottin & Planes (2013) from the Marquesas. The five species share the following combination of characters: dorsal rays usually X,16; anal rays usually III,7; third dorsal spine prolonged at least in males; third segmented anal-fin ray longest; lateral-line scales 40–50; no auxiliary scales on body; and interopercle and subopercle with distinct serrations in adults. Males of P. tequila , P.

flavicauda , P. randalli and P. pulcherrimus are also unusual in exhibiting weak to pronounced hypertrophy of the upper lip (see Remarks below). The condition of the upper lip is unknown in P. oumati , as the species is known only from the female holotype.

Pseudanthias tequila is distinguished from at least P. randalli , P. pulcherrimus and P. flavicauda by male live colouration. The live colouration of the single known female specimen of P. oumati is distinctive in being more-orless uniformly yellow. Williams et al. (2013) noted that the holotype was collected from a group of similarly coloured individuals. Given that Pseudanthias species are protogynous hermaphrodites that typically live in shoals consisting of female and juvenile individuals guarded by a smaller number of males, it is likely that the shoal observed by Williams et al. included at least one male, and that males of the species are also predominantly yellow. Males of the remaining species are shown in Figure 4 . We also include an additional, undescribed species in the figure. That species, hereafter termed Pseudanthias sp., is known on the basis of aquarium specimens collected from Kirimati in the Line Islands. Male colouration characters distinguishing the five species are summarised in Table 2.

Aside from live colouration, P. tequila differs: from P. flavicauda in being deeper bodied (33.7–35.2 vs 30.1– 32.5 % SL), with a longer second anal-fin spine (18.4–20.6 vs 16.8–17.6 % SL), and fewer circumpeduncular scales (24 vs 26–27); from P. oumati in being shallower bodied (33.7–35.2 vs 40 % SL), with fewer lower limb gill rakers (21–23 vs 28) and fewer circumpeduncular scales (24 vs 27); from P. randalli in having a shorter predorsal length (27.5–29.5 vs 30.2–32.4 % SL), a longer second anal-fin spine (18.4–20.6 vs 15.5 –17.0 % SL) and more pectoral-fin rays (18 vs 16-18, usually 17); and from P. pulcherrimus in having more lateral-line scales (46–49 versus 40–45).

In describing P. mica from Lembatta Island (Lesser Sunda Islands, Indonesia), Allen & Erdmann (2012) suggested a close relationship to P. randalli and P. pulcherrimus . Williams et al. (2013) also suggested a close relationship between the three species and P. oumati . However, aside from several minor differences (such as number of gill rakers), Allen & Erdmann’s description of P. mica agrees well with Katayama & Masuda’s (1982) original description of Anthias leucozonus (now Pseudanthias leucozonus ) from southern Japan, and it is highly probable that the two species are closely related. Both nominal species depart from P. tequila , P. oumati , P. randalli and P. pulcherrimus in having fewer lateral-lines scales (36–38 versus 40–50).

Etymology. The specific epithet refers to the alcoholic beverage tequila sunrise, alluding to the vibrant life colours of the males of the species. To be treated as a noun in apposition.

Remarks. Placement of the new species in Pseudanthias should be regarded as provisional. The genus is poorly diagnosed and preliminary analysis of morphological characters by the first author suggests some species currently included in the genus may be more closely related to other genera, such as Nemanthias Smith (1954) , Tosana Smith & Pope (1906) , Tosanoides Kamohara (1953) , Luzonichthys Herre (1936) , Rabaulichthys Allen (1984) and Anatolanthias Anderson, Parin & Randall (1990) . Classification within the genus is also problematic. Generally species have been assigned to either the nominate subgenus ( Pseudanthias ) or to the subgenus Mirolabrichthys Herre (1927) . Randall & Lubbock (1981) recognised the latter on the basis of a single character, upper lip of males hypertrophied. However, Randall & Pyle (2001) noted that this character is expressed to an intermediate degree in P. flavicauda , and Heemstra & Akhilesh (2012) reported similar development of the upper lip in P. pulcherrimus . Various degrees of hypertrophy also occur in at least P. randalli and P. tequila . This might be taken as evidence for placing all four species (and possibly P. oumati , for which males are unknown) in the subgenus Mirolabrichthys . However, upper lip hypertrophy also occurs in Nemanthias . Moreover, taken in the context of other characters (including specialisations associated with orientation of the first dorsal pterygiophore, pectoral ray ornamentation, number of epineural bones, and predorsal formulae), Mirolabrichthys as diagnosed by Randall & Lubbock (1981) does not appear to be monophyletic, and hypertrophy appears to have arisen multiple times within anthiadines. Preliminary molecular studies also support this conclusion (e.g. Williams et al. 2013: fig. 13).

Figures

FIGURE 1. Pseudanthias tequila n. sp., KPM-NI 3759, 59.3 mm SL male holotype, Ototo-jima Island, Chichi-jima Islands, Ogasawara Islands, Japan. Photo (KPM-NR 51086 B) by H. Senou.

FIGURE 2. Pseudanthias tequila n. sp., KPM-NI 3758, 31.5 mm SL female paratype, Ototo-jima Island, Chichi-jima Islands, Ogasawara Islands, Japan. Photo (KPM-NR 51087 B) by H. Senou.

FIGURE 3. Pseudanthias tequila n. sp., KPM-NI 3759, 59.3 mm SL, holotype, x-radiograph. Radiograph (KPM-NR 51086 C) by H. Senou.

FIGURE 4. Males of selected Pseudanthias species: A) P. tequila n. sp., Ototo-jima, Chichi-jima Islands, Ogasawara Islands, Japan (KPM-NR 179391 A, photo by O. Morishita); B) P. tequila n. sp., Tinian, Mariana Islands (photo by N. Tsuji); C) P. pulcherrimus, aquarium specimen (not retained) from the Maldives (photo by Y. K. Tea); D) P. randalli, Kwajalein, Marshall Islands (photo by J. Johnson); E) P. flavicauda, Fiji (photo by J. E. Randall); F) P. sp., Kirimati, Kiribati (photo by D. J. Linehan).

FIGURE 5. Pseudanthias tequila n. sp., female, Ototo-jima, Chichi-jima Islands, Ogasawara Islands, Japan. Photo by S. Kobayashi.

FIGURE 6. Group of Pseudanthias tequila n. sp., Tinian, Mariana Islands, Micronesia. Photo by N. Tsuji.

FIGURE 7. Distribution records for Pseudanthias tequila.