Plectranthias wheeleri Allen 1985: 2508 Paxton et al. 1989: 507 Baldwin & Johnson 1993: 244 Hutchins 2001: 30 Allen et al. 2006: 991 Parenti & Randall 2020: 30 Review of Australian species of Plectranthias Bleeker and Selenanthias Tanaka (Teleostei: Serranidae: Anthiadinae), with descriptions of four new species Gill, Anthony C. Pogonoski, John J. Moore, Glenn I. Johnson, Jeffrey W. Zootaxa 2021 2021-01-26 4918 1 1 116 Gill & Pogonoski & Moore & Johnson, 2021 Gill & Pogonoski & Moore & Johnson 2021 [151,470,994,1021] Actinopterygii Serranidae Plectranthias Animalia Perciformes 80 81 Chordata species mcgroutheri sp. nov.   Figures 34–35; Tables 1–17, 26–27  Common name: McGrouther’s Perchlet     Plectranthias wheeleri[non Randall 1980].—  Allen 1985: 2508(checklist, Western Australia).—  Paxton et al.1989: 507(checklist, North West Shelf, Australia).—  Baldwin & Johnson 1993: 244(list of comparative specimens).—  Hutchins 2001: 30(checklist).—  Allen et al.2006: 991(checklist). —  Parenti & Randall 2020: 30(checklist; in part).    Holotype. AMSI.22828-010, 74.0 mm SL, Australia, North West Shelf, 190 kmnorthwest of Port Hedland, 19°01′S, 117°12′E,  200–202 m, Engeltrawl, M. McGrouther& J. R. Paxtonaboard RV  Soela,  14 Apr 1982.     Paratypes. AMS.  I22828-034, 76 mmSL (cleared and stained), collected with holotype;  AMSI.22828-035, 5: 49.9–68.6 mmSL, collected with holotype;  CSIRO H 6378-20, 59.2 mmSL,  CSIRO H 6378-21, 2: 32.6–42.0 mm SL,  CSIRO H 6378-22, 2: 24.1–31.6 mmSL, Western Australia, west of Exmouth Gulf, 21°59.17′S, 113°49.20′Eto 21°59.79′S, 113°49.14′E,  165–166 m, beam trawl,  FRV  Southern Surveyor,  11 Dec 2005(SS1005/153);  NMV  A 29687-009, 63.4 mmSL, Australia, Western Australia, MermaidL24 transect, 17°29.23′S 120°27.63′Eto 17°29.72′S 120°28.07′E,  184–187 m, beam trawl, M.F. Gomonaboard  RV  Southern Surveyor,  20 June 2007; WAMP.35175- 001, 55.3 mmSL, collected with  CSIRO H 6378-20,  CSIRO H 6378-21and  CSIRO H 6378-22.   Diagnosis.The following combination of characters distinguishes  P. mcgroutherifrom congeners: segmented dorsal rays 16; third dorsal spine longest; pectoral rays 14, with all but uppermost branched in adults; lateral line complete, consisting of 27–30 tubed scales; no scales on maxilla, mandibles or lower part of snout; lower part of preopercle with two enlarged antrorse serrations; head length 41.9–44.7 % SL; snout length 7.1–9.2 % SL.   Description.Dorsal rays X,16, all segmented rays branched; anal rays III,7, all segmented rays branched; pectoral rays 14/14, all rays unbranched; pelvic fin I,5, all segmented rays branched; upper procurrent caudal-fin rays 7 (6–7); lower procurrent caudal-fin rays 7 (5–7); principal caudal-fin rays 9+8; branched caudal fin rays?+? (8+7); total caudal-fin rays 31 (29–31); lateral line complete with 28/30 (27–30) scales; scales above lateral line to origin of dorsal fin 3/3 (3–4); scales above lateral line to base of fifth dorsal spine 2/2 (2–4); scales below lateral line to origin of anal fin 11/11 (11–12); diagonal rows of scales on cheek 9 (7–9), including 1 (1–2) over preopercular canal; predorsal scales 24 (21–28), extending to middle to anterior nostrils; circumpeduncular scales 14 (13–15); gill rakers 5+10 (5–6+10–13=15–19), the upper 4 (4–5) and lower 3 (2–5) rudiments; pseudobranchial filaments 18 (15–20); branchiostegal rays 7.   FIGURE 34.  Plectranthias mcgroutheri, A) AMS I.22828-010, 74.0 mm SL, preserved holotype, North West Shelf, Australia; B) AMS I.22828-010, holotype, radiograph; C) NMV A 29687-009, 63.4 mm SL, freshly dead paratype, 190 km west of Broome, Western Australia. Photos by (A) A.C. Gill, (C) M.F. Gomon; radiograph by A. Hay and S.E. Reader.   TABLE 26.Morphometric values for  Plectranthias mcgroutheri n. sp.expressed as percentrages of SL. * indicates where a measurement could not be made, owing to damage.    Holotype AMS I.22828-010 Paratypes  Size class (mm SL) 20.0–29.9 30.0–39.9 40.0-49.9 50.0-59.9 60.0-69.9  n: SL (mm) 74.0 1: 24.1 2: 31.6–32.6 2: 42.0–49.9 2: 55.3–59.2 5: 60.6–68.6  Greatest body depth 37.2 32.0 32.3–33.4 35.7–39.5 36.8–40.7 36.2–38.1  Body depth at anal-fin origin 34.9 29.5 29.7–30.1 32.9–33.1 32.9–33.6 32.5–35.4  Body width 20.8 13.7 14.6–17.8 18.6–19.2 17.9–18.8 18.1–20.8  Head length 43.2 41.9 42.6–43.0 44.3–44.5 41.9–44.7 42.4–44.4  Snout length 8.2 7.1 8.2–9.2 7.1–7.6 7.8–8.8 7.3–8.5  Orbit diameter 12.3 13.3 13.3–13.8 14.2–14.3 12.8–14.5 12.4–13.5  Bony interorbital width 4.6 2.9 2.8–4.0 3.8 3.6–4.6 4.6–5.0  Upper jaw length 19.3 17.4 18.0–19.0 19.0–19.6 18.6–20.1 19.4–21.0  Maxilla width 5.7 5.4 6.0–6.1 6.0–6.2 5.8–5.9 5.7–6.5  Caudal peduncle length 20.7 19.1 20.6–21.8 18.1–20.4 17.2–19.4 18.2–19.6  Caudal peduncle depth 13.2 12.9 12.3–13.8 13.1–13.2 13.7 12.4–13.7  Predorsal length 39.6 41.1 38.6–42.0 38.7–42.1 40.0–40.2 39.4–40.6  Preanal length 71.8 67.2 67.5–70.9 69.3–71.4 69.8–75.0 67.7–72.8  Prepelvic length 40.5 35.3 36.1–37.1 37.0–37.4 37.8–39.4 36.5  Dorsal fin base length 50.7 48.5 47.2–49.7 51.2–52.5 52.4–52.7 51.2–54.5  First dorsal spine 5.5 6.2 6.6–7.1 7.1 5.8–7.4 5.5–7.4  Third dorsal spine 19.9 17.4 16.1–19.3 21.0 21.2–24.8 20.7–24.0  Fourth dorsal spine 17.7 18.3 18.7 18.8–19.0 19.7–20.9 18.1–21.3  ......continued on the next page  TABLE 26. (Continued)    Holotype AMS I.22828-010 Paratypes  Fifth dorsal spine 15.9 17.0 16.3–17.4 17.6–17.8 18.1–18.4 15.4–19.0  10th dorsal spine 8.4 7.9 8.6 8.6 8.9–10.3 8.5–9.5  First segmented dorsal ray * 13.7 13.3–15.6 * 15.9–17.0 *  Longest segmented dorsal ray (number) 18.6 (9) * 19.3 (5) 18.2 (9) 19.0 (5) 17.2 (6)  Anal fin base length 14.7 15.8 13.3–15.5 14.5–15.8 14.6–16.0 14.7–17.2  First anal spine 9.2 9.1 9.5–9.8 9.2–10.2 10.8–11.0 8.5–10.4  Second anal spine 19.1 19.9 20.6–20.9 20.8–21.7 21.6–23.0 18.3–22.8  Third anal spine 14.1 17.0 14.9–16.3 16.6–16.7 17.4–18.3 14.8–17.2  First segmented anal ray 17.8 20.7 19.9 20.0–20.4 20.4–21.2 18.6–22.7  Longest segmented anal ray (number) * 22.4 (3) 21.2 (2) 22.1–23.0 (2–3) 21.8–24.1 (2) 23.1–24.3 (2–3)  Caudal fin length 28.8 * * * 26.0–30.0 32.7  Caudal concavity 5.5 * * * 1.0–2.5 7.8  Longest pectoral-fin ray (number) * * 35.3–36.1 (9) 35.5 (8) 32.9–35.8 (7–9) 37.0 (8)  Pelvic fin spine 13.8 15.8 17.1–17.2 16.0–17.6 16.1–16.6 15.5  Pelvic fin length 22.8 24.5 22.8–23.0 24.2–25.0 25.5–25.7 25.1 Vertebrae 10+16; supraneurals 3; predorsal formula 0/0+0/2/1+1; dorsal pterygiophores in interneural spaces 9–13 1/1/1+1/1+1/1+1 (1/1/1+1/1+1/1 or 1/1/1+1/1+1/1+1); no trisegmental pterygiophores associated with dorsal fin; terminal dorsal pterygiophore in interneural space 18 (17–18); no trisegmental pterygiophores associated with anal fin; terminal anal pterygiophore in interhaemal space 5 (4–5); ribs present on vertebrae 3 through 10; epineurals present on vertebrae 1 through 13 (12–13); 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; proximal tip of first anal-fin pterygiophore near distal tips of parapophyses on vertebra 10 ( Figure 34B). Dorsal-fin spines with fleshy tabs on their distal tips, the tab on third spine longest and pennant-like; third dorsal spine longest (fourth spine slightly longer in 24.1 mmSL paratype); dorsal fin incised before first segmented-fin ray (tenth spine 52.1–64.9 % length of first segmented ray); second anal-fin spine longest and stoutest; anal fin pointed, second or third segmented ray longest; caudal fin emarginate; lower 8 pectoral fin rays thickened, with membranes between thickened rays incised; eighth (seventh to ninth counting from dorsal-most) pectoral ray longest, reaching vertical through middle of anal-fin base; pelvic fins short, not reaching anus, second segmented ray longest. Morphometric data are summarised in Table 26. Mouth large, reaching or almost reaching vertical through posterior margin of orbit; maxilla expanded posteriorly, with long, low, lateral ridge running parallel to dorsal margin, small splint-like supramaxilla present; mouth terminal; upper jaw with pair of fixed outer canines at front, a band of depressible teeth 5–6 rows at symphysis, reducing to 3–4 rows wide posteriorly, the outer row slightly enlarged, and inner teeth in band across front of jaw enlarged and caniniform; lower jaw with 5 rows of teeth at front of jaw, reducing to a single row posteriorly, the teeth in band near symphysis slightly curved, with 1-2 enlarged in outer row on middle of jaw; vomer with 2–3 rows of small conical teeth arranged in a chevron; palatine with a band of 2–3 rows of small conical teeth; ectopterygoid and mesopterygoid edentate; tongue edentate, slender with rounded tip. Opercle with 3 flat spines, middle spine longest; preopercle with 10–27 serrations on posterior border, those nearest the angle largest, with an additional 2 enlarged antrorse serrations on ventral border; interopercle with 1–8 usually strong serrations; subopercle with 1–7 usually strong serrations. Anterior nostril positioned at middle of snout, tubular with small flap on posterior rim; posterior nostril at anterior border of orbit, with slightly raised rim, sometimes with small flap anteriorly. Scales ctenoid with peripheral cteni; lateral line broadly arched over pectoral fin following body contour to caudal-fin base; no scales on chin, branchiostegal membranes, maxilla or snout; no auxiliary scales on head or body; soft dorsal and anal fins with low scaly sheaths basally, with some small scales extending on to fin membranes; caudal fin with scaly basal sheath, with small scales extending on to basal third to half of fin membranes; pectoral fins with basal sheath and small scales extending on to fin membranes. Colour in life (based on colour photos of 63.4 mmSL paratypewhen freshly dead ( Figure 34C) and of 59.2 mmSL paratypeafter five years frozen): head and body tan to pale pink; snout, nape and dorsal part of head red to orange-red; posterior part of preopercle and adjacent part of operculum mauve to dusky purple; area behind and narrowly below eye mauve to dusky purple; pectoral base and ventral contour of breast pale pink to dusky purple; lower part of abdomen pale tan or pale pink to white; small dusky purple spot over anus; red to orange-red roughly wedgeshaped blotch extending from beneath anterior half of dorsal base to mid-side; second roughly wedge-shaped, broad red to orange blotch extending from between bases of about seventh dorsal spine and seventh segmented dorsal ray to anterior third of anal-fin base; caudal peduncle and posterior part of body behind red wedge pale pink to reddish tan; a column of three to five small, equally spaced bright yellow to red spots on posterior part of caudal peduncle, just anterior to caudal base, with an additional small yellow to red spot about midway along caudal peduncle, just above ventral border, and several additional yellow to red spots over posterior few lateral-line scales; 59.2 mmSL paratypewith additional bright yellow spots scattered over head and body; pectoral fins bright yellow, with orangered spot over upper half of basal part of fin; remaining fins bright yellow, reddish orange distally. Colour in preservative: Pale tan, sometimes with dusky grey markings on nape; wedge-shaped blotches beneath dorsal-fin base may be indistinctly present, dusky grey; tips of fleshy tabs on dorsal-fin spines dusky brown.   Habitat and distribution.Known only from the holotypeand six paratypestrawled in  200–202 m, 190 kmnorthwest of Port Hedland, Western Australia, a paratypetrawled in  184–187 m, 190 kmwest of Broome, Western Australia, and six paratypestrawled in  166 m, west of Exmouth Gulf, Western Australia( Figure 35). Specimensof  P. lastiwere also collected in the first-mentioned trawl. Noother details on habitat are available.   Comparisons.  Plectranthias mcgroutheriis similar to  P. knappi Randall, 1996from the Visayan Sea, Philippines, and keys to that species using Randall’s (1996)key. It is also close to  P. maekawa Wada, Senou & Motomura, 2018from the Tokara Islands, Ryukyu Islands, Japan. The three species are unique within the genus in having the following combination of characters: segmented dorsal rays 16 ( 15–16 in  P. maekawa); third dorsal spine longest; pectoral rays 14, most rays branched; lateral line complete, consisting of 27–30 tubed scales; no scales on maxilla, mandibles or lower part of snout; and lower part of preopercle with two enlarged antrorse serrations. Comparisons between the three species are difficult as  P. knappiremains known only from the 66 mmSL holotypeand  P. maekawais known only from the 58.2 mmSL holotypeand two paratypes( 62.3–65.7 mmSL). However, the three species appear to differ substantially in various morphometric details ( Table 27). In addition to those characters,  P. knappiappears to have a longer dorsal-fin base than the other two species. Randall’s (1996)value of 33.5 % SL for the dorsal-fin base of  P. knappiis obviously in error. His figure 2 of the holotypeindicates a value of ca 58.5 % SL, which is substantially higher than recorded for  P. mcgroutheri(47.2–54.5 % SL) or  P. maekawa(49.4–51.2 % SL).  Comparison of mitochondrial COI barcode DNA sequences with available sequences for other  Plectranthiasprovided a closest match with  P. retrofasciatus(5% uncorrected difference). The two species have similar live colorations, particularly in having wedge-shaped red markings extending from the dorsal-fin base. They are distinguished by pectoral ray counts ( 14 in  P. mcgroutheriversus 13 in  P. retrofasciatus) and lower jaw dentition (inner row of teeth not enlarged versus enlarged).  Allen (1985)and subsequent authors have identified the AMS typespecimens of  P. mcgroutherias  P. wheeleri. The two species are distinguished by their pectoral ray counts ( 14 in  P. mcgroutheriversus 13 in  P. wheeleri), and live coloration (see Wada et al., 2018: fig. 5).  Remarks.The specific epithet is for our friend and colleague Mark McGrouther, former collections manager at AMS, who collected the holotypeand six of the paratypes, in recognition of his contribution to Australian ichthyology and support given to all the authors over an extended timeframe. A moderate-sized  Plectranthiasspecies, largest specimen 76 mmSL. Allen’s (1985)identification of the AMS typesof this species forms the sole basis for records of  P. wheelerifrom Australia. The latter species therefore should be removed from Australian faunal lists. Although the record of  P. wheeleriin Allen & Swainston (1988)and subsequent editions pertains to this species, the accompanying illustration appears to be based on true  P. wheeleri. 3026471389 1982-04-14 AMS, R, RV M. McGrouther & J.R. Paxton Australia 201 -19.016666 North West Shelf 1273 117.2 Port Hedland 80 81 1 holotype 3026471540 I22828 [199,1185,1337,1364] 1982-04-14 AMS M. McGrouther & J.R. Paxton Australia 201 -19.016666 North West Shelf 1273 117.2 Port Hedland 80 81 I22828-034 1 paratype 3026471424 1982-04-14 AMS M. McGrouther & J.R. Paxton Australia 201 -19.016666 North West Shelf 1273 117.2 Port Hedland 80 81 1 paratype 3026471406 [645,1010,1373,1400] CSIRO Australia 80 81 H 6378-20 1 paratype 3026471377 CSIRO Australia 80 81 H 6378-21, 2 1 paratype 3026471521 CSIRO Australia 166 -21.9965 Exmouth Gulf 12 113.819 80 81 H 6378-22, 2 1 Western Australia paratype 3026471441 [744,1335,1443,1470] 2005-12-11 FRV Australia Southern Surveyor 80 81 1 Western Australia paratype 3026471425 A 29687 NMV M. F. Gomon Australia 186 -17.495333 Mermaid 13 120.467834 80 81 A 29687-009 1 Western Australia paratype 3026471323 [825,1249,1515,1541] 2007-06-20 RV Australia Southern Surveyor 80 81 1 Western Australia paratype 3026471309 [525,738,1550,1577] CSIRO Australia 80 81 H 6378-20 1 Western Australia paratype 3026471453 [749,1006,1550,1577] CSIRO Australia 80 81 H 6378-21 1 Western Australia paratype 3026471509 [1014,1227,1550,1577] CSIRO Australia 80 81 H 6378-22 1 Western Australia paratype