Chaunax atimovatae, Ho, Hsuan-Ching & Ma, Wen-Chun, 2016

Ho, Hsuan-Ching & Ma, Wen-Chun, 2016, Revision of southern African species of the anglerfish genus Chaunax (Lophiiformes: Chaunacidae), with descriptions of three new species, Zootaxa 4144 (2), pp. 175-194 : 176-181

Chaunax atimovatae sp. nov.

New English name: Southern frogmouth Figures 1 A–C, 2; Tables 1–3.

Holotype. SAIAB 81724 (149), 26°10.2'S, 33°17.6'E, off Mozambique, 505–509 m, 30 Sep. 2007.

Paratypes. 13 specimens, 104–211 mm SL. AMS I.28137-006 (2, 108–111), 22°19' 06"S, 43°06' 06"E, NW Tulear , Madagascar, 330–335 m, 2 Dec. 1988 . MNHN 1977-0030 (1, 119), 22°17'10"S, 43°4'1"E, Madagascar, 450 m, 29 Nov. 1973 . MNHN 1977-0036 (1, 105), 12°40'59"S, 48°16'1"E, Madagascar, 314 m, Apr. 1971 . SAIAB 3306 (1, 118), KwaZulu-Natal, South Africa, 238 m, 10 Jan. 1973 . SAIAB 11484 (1, 139), off Natal , KwaZulu- Natal, South Africa, 146 m, 11 Jan. 1973 . SAIAB 34164 (1, 211), Maputo, southern Mozambique, Dec. 1987 . SAIAB 74601 (3, 104–131), 18°2.1'S, 37°37.2'E, Beira , northern Mozambique, 162–200 m, 12 Aug. 2002 . SAIAB 81904 (1, 106), 25°5.5'S, 35°18.4'E, off Mozambique, 347–353 m, 7 Oct. 2007 . USNM 307534 (2, 122–162), 22°19'51"S, 43°06'06"E, northern Tulear , Madagascar, 330–335 m, Vityaz, cr. 17, st. 2644, 2 Dec. 1988 .

Non-types (*indicates specimens with meristic data taken). Madagascar: MNHN 1977-0023 (2, 69.6–82.1), 25°28'59"S, 46°46'1"E, 350–360 m, 30 May 1973 . MNHN 1977-0027 (1, 72.8), 23°36'0"S, 43°31'5"E, 395–410 m, 26 Feb. 1973. MNHN 1977-0029 (3, 43.1–111), 22°18'0"S, 43°4'8"E, 400 m, 27 Nov. 1973. MNHN 1977-0033 (2, 35.9–67.8), 18°55'01"S, 43°55'59"E, 250 m, 24 Nov. 1973. MNHN 1994-0312 (1, 107), 20°57' 0"S, 55°13'59"E, Réunion Island, 450–580 m, 1 Sep. 1982 . MNHN 1994-0314 (1, 76.4), 20°49' 59"S, 55°34'59"E, Réunion Island, 605–620 m, 4 Sep. 1982 . MNHN 1994-0315 (2, 67.0–131), 20°57'0"S, 55°13'59"E, 300–410 m, 9 Sep. 1982. MNHN 2013-1225 (2, 56.7–83.8), 22°14'6"S, 43°4'5"E, 470–475 m, 2 Dec. 1973. MNHN 2014-1107 (1, 123), 15° 35'8.4"S, 45°41'55.8"E, 197–217 m, 10 Jul. 2009. MNHN 2014-1169 (5, 39.1–71.1), 15°34'45"S, 45°42'30"E, 227–283 m, 10 Jul. 2009. MNHN 2014-1211 (1, 87.6), 15°33'37.2"S, 45°42'5.4"E, 350–580 m, 11 Jul. 2009. MNHN 2014-1264 (2, 31.3–35.2), 14°29'3"S, 47°26'50.4"E, 257– 251 m, 6 Jul. 2009. MNHN 2014-1602 (1, 68.5), MNHN 2014-1628 (1, 37.7), 12°30'16.8"S, 48°23'12"E, 301– 298 m, 27 Jun. 2009. MNHN 2014-1664 (5, 68.8– 101), 15° 34'12.612"S, 45°43'10.812"E, 287–450 m, 10 Jul. 2009. MNHN 2014-1699 (1, 39.5), 14°51'56.4"S, 46°56'34.2"E, 236–297 m, 13 Jul. 2009. MNHN 2014-1719 (1, 95.5), 13°23'31.2"S, 47°58'4.2"E, 3 Jul. 2009. MNHN 2014-1756 (2, 52.6–79.7), 14°29'39.6"S, 47°26'27"E, 379– 332 m, 14 Jul. 2009. MNHN 2014-1764 (1, 87.8), 12°32'7.8"S, 48°12'27"E, 485– 468 m, 27 Jun. 2009. MNHN 2014-1781 (4, 38.7–105), MNHN 2014-1815 (1, 95.4), MNHN 2014-1838 (2, 33.5–60.1), MNHN 2014-1840 (1, 40.9), 14°49'53.4"S, 46°59'9"E, 446– 340 m, 7 Jul. 2009. MNHN 2014-1846 (1, 110), 12°46'18"S, 48°12'48.6"E, 355–380 m, 2 Jul. 2009. MNHN 2014-1855 (3, 31.3–32.7), 14°30'10.8"S, 47°26'35.4"E, 325– 274 m, 6 Jul. 2009. MNHN 2014-1878 (2, 22.0–22.9), 14°48'12"S, 46°59'9"E, 620–637 m, 7 Jul. 2009. MNHN 2014-1900 (1, 69.3), 15°25'4.8"S, 46°0'16.2"E, 313– 274 m, 12 Jul. 2009. MNHN 2014-1962 (2, 38.0–40.0), 12°31'18.6"S, 48°19'33"E, 346–376 m, 27 Jun. 2009. MNHN 2014-2169 (1, 79.2), 12°43'15.6"S, 48°13'1.8"E, 442–491 m, 29 Jun. 2009. SAIAB 189524 (3, 31.5–45.2), 25°28'S, 44°25'E, Sud-Est Pointe Barrow , 203–210 m, 10 May 2010, coll. M. Lee & S. Ribes . SAIAB 189525 (1, 31.5), 25°03'S, 43°59'E, Sud-Ouest Pointe Barrow , 300–309 m, 11 May 2010, coll. M. Lee & S. Ribes . * USNM 307546 (2, 60.0– 100), 22°19'30"S, 43°03'12"E, northern Tulear , 450–500 m, Vityaz, Cr. 17, st. 2645, 2 Dec. 1988 . South Africa: * SAIAB 4709 (1, 76.0), 34°02'S, 25°42'E, Algoa Bay , Eastern Cape, 27 May 1970 . * SAIAB 4710 (1, 150), 32°09'S, 29°00'E, Xora River mouth, Eastern Cape, Aug. 1947 . * SAIAB 16533 (1, 77.0), 29°13'S, 31°29'E, Tugela River mouth, KwaZulu-Natal, 1920. * SAIAB 49355 (1, 84.0), 35°1.3'S, 19°44'E, off west coast, 145 m, 5 Jul. 1986 . Mozambique: * SAIAB 28513 (1 of 3, 104), S of Maputo, Dec. 1987 . No data: *SAIAB 4713 (1 of 5, 125).

Diagnosis. A species of the Chaunax abei species group with the following combination of characters: mixture of bifurcate and simple spinules on dorsal surface; when fresh, dorsal surface with green spots surrounded by yellow, mostly inter-connected; when preserved, dorsal surface with brown spots loosely arranged; 9 or 10 gill rakers on second gill arch; and usually 12 or 13 neuromasts in pectoral series and 34–36 in lateral-line proper.

Chaunax atimovatae Chaunex heemstraorum Chaunax hollemani

sp. nov. sp. nov. sp. nov.

H Types H All types H All types

(mm) 149 104.0$216.0 (n=13) 163 95.1$163.0 (n=9) 194.5 114.9$178.7 (n=5)

SL Mean (Range) SD Mean (Range) SD Mean (Range) SD Description. Morphometric and meristic data are provided in Tables 1–3; data for holotype is provided below followed by range for types in parentheses.

Dorsal-fin rays III, 12; pectoral-fin rays 13 (13, rarely 12); anal-fin rays 7; caudal-fin rays 9. Head length 2.5 (2.3–2.6) in SL; head width 5.7 (5.6–6.2) in SL and 2.3 (2.3–2.5) in HL; pre-dorsal length 1.9 (1.9–2.2) in SL; pregill opening length 1.5 (1.5–1.6) in SL; pre-preopercular length 3.7 (3.5–3.9) in SL and 1.5 (1.4–1.6) in HL; upper jaw 5.1 (4.6–5.0) in SL and 2.0 (1.9–2.1) in HL; illicial length 8.4 (7.0–9.4) in HL; eye diameter 6.6 (5.2–6.6) in HL; post-dorsal-fin length 6.2 (5.4–6.4) in SL and 2.5 (2.0–2.8) in HL; post-anus length 3.2 (3.0–3.7) in SL and 1.3 (1.1–1.5) in HL; post-anal-fin length 6.5 (6.5–7.6) in SL and 2.6 (2.6–3.1) in HL; caudal-peduncle depth 4.9 (4.8– 5.3) in HL; caudal-fin length 3.5 (3.1–3.6) in SL and 1.4 (1.3–1.5) in HL.

Head globular, skull elevated posteriorly; trunk and tail robust, weakly compressed, tapering posteriorly; ventral surface of belly flattened; skin thick, loose and flaccid; caudal peduncle short, slightly depressed. Eyes rounded, directed laterally, covered by dermal membrane, broadly connected to adjacent skin, forming clear window; interspace between eyes broad, convex.

Illicium relatively slender, its length less than eye diameter; esca depressed, forming a large central plate bearing many dark brown cirri; second dorsal-fin spine close to illicium, embedded under skin and not detectable externally; third dorsal-fin spine situated at about midpoint of pre-dorsal distance, embedded beneath skin. Illicial trough oval, slightly concave, uniformly narrow, its length about twice its width. Origin of soft dorsal fin slightly behind middle of body; pectoral fin emerging laterally near middle of body, slightly anterior to vertical through gill opening; pelvic fin on breast, well anterior to pectoral fin; anus situated about three-fourths of way along body; anal-fin origin about four-fifths of way along body, tip nearly reaching caudal-fin base when depressed.

Both nostrils anterior to eye; anterior nostril surrounded by fleshy membrane, its rim taller posteriorly than anteriorly; posterior nostril a circular depression; mouth wide, superior, its opening nearly vertical; lower jaw robust, protruding slightly in front of upper jaw; maxilla tapering, narrow dorsally, broadly expanded ventrally; blunt spine on symphysis of lower jaw.

Broad transparent membrane on first gill arch; first ceratobranchial well-connected to opercular wall, and first epibranchial entirely free of it; gill filaments present on second to fourth gill arches, two rows of gill filaments on second and third gill arches, single row of gill filaments on fourth gill arch; filaments on inner rows of third and fourth gill arches about two-thirds length of filaments on other arches; inner surface of fourth gill arch completely connected to body. Single row of 14 (12–15) rakers on 1st gill arch, 3 (3–4) on upper limb and 11 (8–11) on lower limb, 10 (9 or 10) rakers on outer row of 2nd arch, 9 (9 or 10) rakers on outer row of 3rd arch, and single row of 8 (7 or 8) rakers on 4th arch.

Interspaces of lateral-line neuromast complex slightly longer than width of complex; 3 (2–4, usually 3) pairs of short spines bridging each neuromast. Lateral-line neuromast counts: supraorbital (AB) 11 (11 or 12); premaxillary (AC) 8; upper preopercular (BD) 2; infraorbital (CD) 7 (6 or 7); lower preopercular (DG) 3; mandibular (EF) 6 (5 or 6); hyomandibular (FG) 3; pectoral (GH) 14 (11–14); anterior lateral-line proper (BB') 4 (4 or 5); supratemporal (BB) 6; and lateral-line proper (BI) 35 (32–37), including 3 (2 or 3) on caudal-fin base.

Dorsal surface covered by simple, stout spinules, except for eye window, lips, distal fifth of dorsal surface and entire ventral surface of pectoral fin, distal half of dorsal surface and entire ventral surface of pelvic fin, entire anal fin and its base, membranes of dorsal fin, anus, and caudal-fin rays. Broad band of 4–9 rows of spinules in front of illicial trough (3 or 4 rows in specimens smaller than 100 mm SL). Ventral surface covered by slightly shorter, firm spinules. Jaws and body margin along lateral line densely covered with simple, stout cirri; cirri absent from head, jaws and ventral surface.

Coloration. When fresh, background of dorsal surface reddish gray dorsally and pale ventrally; small irregular green spots surrounded by yellow, mostly inter-connected on dorsal surface; bright white flap-like cirri along margins of body and jaws. When preserved, dorsal surface covered by small irregular gray spots on uniformly grayish background; pale ventrally. Cirri on esca dark brown. Gill chamber, buccal cavity and gill rakers pale; peritoneum black with small pale patches.

Size. The largest known specimen has a length of 211 mm SL.

Distribution. Known from the Western Indian Ocean off Madagascar, Mozambique and South Africa, westernmost record appears to be on the southern coast of South Africa ( Fig. 3 ), collected at depths 145– 637 m.

Etymology. The specific name is from a field trip of the "Atimo Vatae" (Madagascan for "deep south"), a trawler from Fort Dauphin, from which many Madagascan specimens were collected, including those in the type series.

Rakers of 1st gill arch n 11 12 13 14 15 16 17 18 19 20 C. apus 5 1 3 2 C. atimovatae 1 4 1 8 4* 1 C. flammeus 1 1

C. heemstraorum 31 4 20 7 * C. hollemani 5 1* 3 1 C. penicillatus 5 1 3 1

C. russatus 2 2 C. suttkusi 7 1 3 3 Rakers of 2nd gill arch n 8 9 1 0 1 1 1 2 1 3 1 4 1 5 C. apus 6 5 1 C. atimovatae 14 6 8 *

C. flammeus 1 1

C. heemstraorum 31 3 22 * 6 C. hollemani 5 5*

C. penicillatus 5 2 3

C. russatus 2 2 C. suttkusi 7 2 4 1 Rakers of 3rd gill arch n 8 9 1 0 1 1 1 2 1 3 1 4 C. apus 6 5 1 C. atimovatae 14 10* 4

C. flammeus 1 1

C. heemstraorum 31 21 10 *

C. hollemani 5 1 4*

C. penicillatus 5 2 3

C. russatus 2 2 C. suttkusi 7 2 4 0 1 Rakers of 4th gill arch n 7 8 9 1 0 1 1 1 2???? C. apus 6 4 2

C. atimovatae 14 3 11 *

C. flammeus 1 1

C. heemstraorum 31 10 20 * 1

C. hollemani 5 1 4*

C. penicillatus 5 5

C. russatus 2 2 C. suttkusi 7 1 5 1

Remarks. Chaunax atimovatae sp. nov. is most similar to Chaunax abei from the northwestern Pacific region in having bifurcated spinules mixed with simple ones on its dorsal surface, but these bifurcated spinules are much less numerous and quite scattered. The background of body of C. atimovatae sp. nov. is grayish with numerous tiny black melanophores (visible under magnification) whereas that of C. abei is pale and lacks this pigmentation. The new species is also similar to C. breviradius from the South China Sea region in having a similar coloration when fresh; it differs from C. breviradius in having bifurcated spinules mixed with simple ones on dorsal surface (vs. simple spinules only), and relatively more neuromasts in the lateral-line proper (BI) (usually 34–36 vs. 30–32).

Figures

FIGURE 1. Chaunax atimovatae sp. nov. A. SAIAB 81724, holotype, 149 mm SL. B. SAIAB 81904, paratype, 106 mm SL. C. Uncatalogued specimen, ca. 21 cm in total, off Maputo, southern Mozambique.

FIGURE 3. Distribution map of Chaunax atimovatae sp. nov. (red squares), Chaunax heemstraorum sp. nov. (green circles) and Chaunax hollemani sp. nov. (black star).