Lophiomus setigerus (Vahl, 1797)

Chen, Hsuan-Pu, Lee, Mao-Ying & Chen, Wei-Jen, 2024, Integrative taxonomy reveals unanticipated hidden diversity in the monotypic goosefish genus Lophiomus (Teleostei, Lophiidae), with description of three new species and resurrection of Chirolophius laticeps Ogilby, 1910, European Journal of Taxonomy 943, pp. 239-287 : 259-264

Lophiomus setigerus (Vahl, 1797)

urn:lsid:zoobank.org:act:2AD07693-B224-4DCE-ADC3-267902D186ED

Figs 7C , 8–9 , 15A , 16G–H ; Tables 1 , 3–6

Lophius setigerus Vahl, 1797: 215 .

Lophius viviparus Bloch & Schneider, 1801: 142 . Objective synonym.

Lophius indicus Alcock, 1889: 302 . Synonymized by Caruso 1983: 13.

Lophiomus longicephalus Tanaka, 1918: 227 . Synonymized by Caruso 1983: 13.

Diagnosis

This species can be separated from other congeners by the combination of dorsal-fin spines 6, pelvic-fin rays mostly 7, pectoral-fin rays 21–23 (mostly 22; Table 6 ), brown body coloration, peritoneum with gray pigmentation, and circular or irregular light pattern on the dark floor of the mouth.

Pseudogene was detected from the DNA barcode region (COI-5P) of COI gene in real Lm. setigerus by primer pair FishF1–FishR1 ( Ward et al. 2005) and cocktail primers C_VF1LFt1–C_VR1LRt ( Ivanova et al. 2007), with stop codon occurring at amino acid position 27 in sample WJC0905 (nucleotide position 79–81 ‘AGG’, but ‘GGA’ normally), and position 79 in samples WJC0905, CFCS006-08, CFCS007-08, CFCS138-08, and CFCS139-08 (nucleotide position 235–237 ‘AGG’, but ‘GGG’ or ‘GGC’ normally) in the COI dataset in this study (Supp. file 3). Numbering of the position starts from the first amino acid or nucleotide site of the gene.

Differential diagnosis

Lophiomus setigerus is most similar to its sibling species Lm. immaculioralis sp. nov. in the brown body coloration and pectoral-fin ray counts. However, it differs by having a higher count of dorsal-fin spines (6 vs 5 in Lm. immaculioralis ), an esca that is mostly pennant-like (tassel-like flap in Lm. immaculioralis ), peritoneum with gray pigmentation (lacking dark or gray pigmentation in Lm. immaculioralis ), and a dark floor of the mouth with circular or irregular light patterns (absence of distinct dark markings in Lm. immaculioralis ). The molecular diagnosis is elaborated in the differential diagnosis section of Lm. immaculioralis .

This species also shares similarities with the newly described species Lm. carusoi sp. nov. in the brown body coloration but differs in having lower counts of dorsal-fin spines (21–23, mostly 22 vs 23–24 in Lm. carusoi ; Table 6 ), a narrower HW (37.4–59.2% HL vs 58.1–68.6% HL in Lm. carusoi sp. nov.; Table 4 ), a narrower ISP (33.0–49.0% HL vs 48.6–56.7% HL in Lm. carusoi ; Table 4 ), and a dark floor of the mouth with circular or irregular light patterns (a light floor of the mouth with a reticulate dark pattern in Lm. carusoi ).

Furthermore, this species can be distinguished from the potentially sympatric newly described species, Lm. nigriventris sp. nov., by its brown body coloration (pale khaki of Lm. nigriventris ), gray peritoneum (dark in Lm. nigriventris ), and a dark floor of the mouth with circular or irregular light patterns (light floor of the mouth with reticulate dark pattern in Lm. nigriventris ).

Material examined

Neotype (designated here)

TAIWAN STRAIT • 155.0 mm SL, sample ID: WJC0905; Taiwan, Pingtung County, Donggang fish port ; ca 100–200 m deep; 13 Apr. 2012; GenBank nos: OR262148 (COI), OR257544 (cytb), OR260582 (rhodopsin), OR257559 (RAG1), OR260592 (COI -like pseudogene); Voucher: NTUM10408 .

Non-type material

NORTHWEST PACIFIC • 284.3 mm SL, sample ID: WJC7223; Japan, Tosa Bay, Mimase fish port ; ca 100–200 m deep; 28 Jan. 2018; GenBank nos: OR262050 (COI), OR257546 (cytb), OR260589 (rhodopsin), OR257560 (RAG1); Voucher: NTUM14414 • 271.1 mm SL, sample ID: WJC7224; same data as for preceding; Voucher: NTUM14414 • 194.3 mm SL, sample ID: WJC7225; same data as for preceding; Voucher: NTUM14414 • 210.8 mm SL, sample ID: WJC7226; same data as for preceding; Voucher: NTUM14414 • 198.1 mm SL, sample ID: WJC7226; same data as for preceding; Voucher: NTUM14414 • 81.9 mm SL, sample ID: WJC7283; Japan, Tosa Bay, Saga fish port ; ca 100–200 m deep; 31 Jan. 2018; GenBank nos: OR262051 (COI), OR257551 (cytb); Voucher: NTUM14414 .

PHILIPPINE SEA • 77.0 mm SL; Philippines, Aurora, stn CP2653; 121°59′45″ E, 16°06′30″ N; 82.7 ± 50 m deep; 20 May 2007; Voucher: ASIZP67752 • 99.0 mm SL; same data as for preceding, stn CP2654; 121°57′30″ E, 16°04′44″ N; 98.4–107 m deep; 20 May 2007; Voucher: ASIZP67786 .

SOUTH CHINA SEA • 107.0 mm SL, sample ID: WJC1791; China, Hainan, Sanya fish port ; ca 100– 200 m deep; 27 Jul. 2010; GenBank nos: OR257545 (cytb), OR260585 (rhodopsin), OR257561 (RAG1); Voucher: NTUM10413 .

TAIWAN STRAIT • 69.3 mm SL, sample ID: WJC7008; Taiwan, Pingtung County, Donggang fish port ; ca 100–200 m deep; 27 Feb. 2017; Voucher: NTUM15739 • 264.1 mm SL, sample ID: WJC5086; Taiwan, Penghu Island, Magong third fish port ; ca 100–200 m deep; 3 May 2015; GenBank nos: OR257549 (cytb), OR260580 (rhodopsin), OR257558 (RAG1); Voucher: NTUM14640 .

WEST PACIFIC • 180.0 mm SL, sample ID: WJC2070; Taiwan, Yilan County, Dashi fish port ; 121°54′03″ E, 24°56′27″ N; ca 100–200 m deep; 9Apr.2013; GenBank nos: OR262149 (COI), OR257548 (cytb), OR260583 (rhodopsin); Voucher: NTUM10414 • 204.0 mm SL, sample ID: WJC5434; same data as for preceding; 16 Jun. 2015; Voucher: NTUM16309 • 198.0 mm SL, sample ID: WJC8060; same data as for preceding; 14 Apr. 2018; Voucher: NTUM15875 • 190.0 mm SL; same data as for preceding; 27 Feb. 2003; GenBank no.: KP201930 (COI); Voucher: ASIZP62543 • 193.0 mm SL; same data as for preceding; GenBank no.: KP201929 (COI); Voucher: ASIZP62544 • 165.0 mm SL; same data as for preceding; GenBank no.: KP201931 (COI); Voucher: ASIZP62545 .

Comparative material

Syntypes of Lophius indicus Alock, 1889

INDIAN OCEAN • 66.4 mm SL; India, Bay of Bengal , 8 km (5 miles) south of Ganjam; ca 51 m (28 fathoms) deep; Voucher: BMNH 1890.11.28.45 • 35.3 mm SL; same data as for preceding; BMNH 1890.11.28.46 .

Redescription of adults

MEASUREMENTS AND MERISTIC COUNTS. Morphometric values given in Tables 3 and 4 . Dorsal-fin spines 6; dorsal-fin rays 8; anal-fin rays 6; pectoral-fin rays 21–23; pelvic-fin rays 6–7; branchiostegal rays 5; quadrate spine 1; interopercular spines 2; vertebrae 18–19; outermost row of premaxillary teeth 17–24 ( Tables 5–6 ).

HEAD AND BODY. Head length short to moderately long (27.3%–36.7% of SL, mean 32.1±0.02%); head width relatively narrow to moderately wide (37.4%–59.2% of HL (mean 54.5 ±0.05%); eyes suboval; anterior half of premaxilla with three rows of enlarged teeth, largest on innermost row, followed by single row of small teeth on posterior half; maxilla toothless; palatine with single row of small teeth, with some enlarged; dentary with three rows of teeth, outer teeth minute and innermost teeth largest; fifth ceratobranchial with two rows of small teeth, forming V-shaped patch; teeth on second and third pharyngobranchials forming small and rounded patches; gill rakers and pseudobranch absent. Palatine spines sharp, with posterior one stronger; frontal ridges and outer surface of maxilla, dentary bones bearing low and conical knobs; hyomandibular and symplectic bones sometimes rugose; frontal spines blunt, with posterior one sharper and stronger; inner sphenotic spines blunt; outer sphenotic spines blunt, stronger than inner one; pterotic spines low, broad, and blunt; parietal, epiotic, and posttemporal spines short and blunt, inconspicuous; articular spines strong and sharp, with single spine anterior to jaw joint; quadrate spines strong and blunt; hyomandibular spines blunt; opercular spines blunt; interopercular spines strong and blunt; subopercular spines strong; cleithral spines strong; humeral spines well developed, with three to four sharp spinelets at its tip; edge of head and caudal peduncle covered by black tendrils.

FINS. Illicium moderate to long (21.4%–32.7% SL, mean 26.2 ±0.03%), without tendrils and reaching beyond basal ⅓ of retracted third dorsal-fin spine; esca ranges from pennant-like flap to flag-like tassel, with cirri, sometimes with one or two dark, stalked, bulb-like appendages at base; second dorsal-fin spine short (15.0%–25.7% of SL, mean 18.7 ± 0.03%), stout, reaching between parietal spines and base of third dorsal-fin spine, with dark tendrils; third dorsal-fin spine short (16.3%–25.5% of SL, mean 21.8± 0.02%), slender, reaching from about ½ of retracted fourth dorsal-fin spine, base imbedded under skin, with dark tendrils; fourth dorsal-fin spine slender, about basal ⅓ imbedded under skin and with dark tendrils, reaching from fifth dorsal-fin spine to origin of dorsal-fin; fifth and sixth dorsal-fin spines short, mostly imbedded under skin and with dark tendrils; first dorsal-fin ray relatively close to second, both imbedded under skin, last two rays short.

COLORATION (PRESERVED). Body color ranges from uniformly grayish to reddish brown, covered by scarce blackish brown spots on dorsal surface; ventral surface pale, with peritoneum gray; floor of mouth dark, with circular light pattern in smaller specimens, but irregular light pattern in larger specimens; dorsal surface of pectoral-fins dark apically, and pigmented as adjacent area of body basally; dorsal-fin pale; caudal fin dark basally and apically, with color pattern same as adjacent area of body.

COLORATION ( FRESH). Similar to preserved coloration, but body color sometimes blackish brown.

Distribution

Northwest Pacific, East China Sea, South China Sea, Timor Sea, and adjacent to Japan, China, Taiwan, and western Australia (this study, Fig. 1 ). It should be noted that the previously recorded ‘ Lm. setigerus ’ from the eastern coast of Australia ( Caruso 1983), New Caledonia ( Kulbicki et al. 1994; Ho & Chen 2013), and the Indian Ocean ( Caruso 1983) should belong to different species according to our phylogenetic and species delimitation results. Thus, previous distribution records of Lm. setigerus from the localities above are considered doubtful and not included in this study. Due to limited sampling, records from the East Pacific ( Mexico) ( De La Cruz-Agüero et al. 1994; Love et al. 2021), Red Sea ( Khalaf 2004; Golani & Bogorodsky 2010), and Africa ( Bianchi 1985; Caruso 1986; Fischer et al. 1990; Sommer et al. 1996) could not be confirmed and are not included in this study either.

Remarks

The type specimens of the species described by Vahl (1797), including Lophius setigerus (= Lm. setigerus ) and Lophius stellatus (= Halieutaea stellata , Ogcocephalidae ), have never been designated or located ( Fricke et al. 2022; R. Fricke pers. com.). Although Fricke et al. (2022) reported one skeleton ( AMS I.25832-004) as a possible syntype of Lm. setigerus (locality: Australia), this specimen has apparently been lost (not held in AMS; A. Hay pers. com.) and was not collected from a locality close to the distribution center of Lm. setigerus inferred in this study. We feel that it is necessary and justifiable to propose a neotype for Lm. setigerus to avoid taxonomic confusion.

Accordingly, a specimen ( NTUM 10408, sample ID: WJC 0905) collected from the Taiwan Strait (off Donggang, Pingtung County, Taiwan), an area that could be encompassed within the type locality of Lm.setigerus – broad sense of ‘China’ in the 18 th century – is designated here as the neotype for Lm. setigerus . This specimen aligns with the original description of Lm. setigerus on the pattern of the floor of the mouth and general appearance ( Table 1 ; Fig. 8D ) (Vahl 1797). Although the original description of Lm. setigerus implied a pectoral-fin rays count of 10 (“ Pinnae pectorales …, decem-radiatae [Pectoral-fin…tenradiated]”; Vahl 1797: 216), this count is distinct from the currently described species of Lophiomus , which typically have more than 21 rays. The discrepancy between the original and present descriptions may be attributed to limitations in microscope and X-ray techniques during that period. Therefore, the meristic counts from the original description are considered unreliable and incomparable.

The name “ Lophius viviparus ” was introduced as an unexplained new name for Lm. setigerus , lacking a voucher specimen designation. It is only accompanied by a brief description “ L. Setigerus, Wahl in Skrivter af Naturh. … Habitat mare Sinense [living in Chinese sea]” ( Bloch & Schneider 1801: 142). Fricke et al. (2022) consequently considered this name as an objective synonym.

Lophiomus longicephalus (for which the type material has also been lost and was thus not examined in this study) ( Fricke et al. 2022) was treated as a junior synonym of Lm. setigerus by Caruso (1983). Morphologically, it resembles Lm. setigerus based on the original description, sharing characteristics such as a brown body coloration, a dark floor of the mouth pattern with white spots, and an overlapped distribution ( Table 1 ). Herein, its synonym status is confirmed.

Regarding Lophius indicus , its syntypes share morphological features with Lm. setigerus , both displaying a brown body color ( Fig. 9A, E ), a dark floor of the mouth with circular light patterns ( Fig. 9C, G ), and 22–23 pectoral-fin rays ( Table 5 ). However, advanced morphological diagnoses are impeded by a lack of a direct morphometric comparison between Lm. setigerus and Lp. indicus due to relatively smaller size of the available Lp. indicus syntypes (SL = 35.3–66.4 mm) ( Tables 3–4 ). Along with its morphological similarity between Lm. setigerus and the lack of further evidence, the synonym status of Lp. indicus with Lm. setigerus suggested by Caruso (1983) is remained.

Chirolophius malabaricus is another synonym of Lm. setigerus ( Caruso 1983) . It was described based on the specimens collected from the Malabar Coast of southwestern India. Since a considerable geographical isolation to either Lp. indicus (type locality: Bay of Bengal) or Lm. setigerus (West Pacific), and a higher count of pectoral-fin rays than other congeners (24 vs 21–23, mostly 22) ( Tables 1 , 3 ), we opine that C. malabaricus could potentially be a distinct species of Lophiomus that should be excluded from the synonymy of Lm. setigerus . However, the absence of a type examination of C. malabaricus and the lack of direct genetic evidence (aside from our discussions on GenBank sequences of “ Lp. indicus ”) prevent us from formally resurrecting this nominal species. Therefore, we tentatively consider it as incertae sedis.

Figures

Fig. 7. Cranial comparative osteology of the three lophiid genera. A. Lophiodes mutilus (Alcock, 1894). B. Lophius litulon (Jordan, 1902). C. Lophiomus setigerus (Vahl, 1797). Scale bars = 10 mm.

Fig. 8. Lophiomus setigerus (Vahl, 1797). A–D. Neotype (NTUM10408, sample ID: WJC0905). E–H. Large specimens (NTUM14414, sample ID: WJC7223). A. Preserved specimen, dorsal view. B. Ditto, ventral view. C. Ditto, fresh specimen. D. Ditto, floor of mouth. E. Preserved specimen, dorsal view. F. Ditto, ventral view. G. Ditto, fresh specimen. H. Ditto, floor of mouth.

Fig. 9. Lophius indicus Alock, 1889. A–D. Large syntype (BMNH 1890.11.28.45). E–H. Small syntype (BMNH 1890.11.28.45.46). A. Preserved specimen, dorsal view. B. Ditto, ventral view. C. Ditto, floor of mouth. D. Ditto, X-ray radiograph. E. Preserved specimen, dorsal view. F. Ditto, ventral view. G. Ditto, floor of mouth. H. Ditto, X-ray radiograph. Photographed by L. Goodayle. © Trustees of the Natural History Museum, London (available under CC-BY 4.0).

Fig. 15. X-ray radiographs in dorsal view and zoom-in images of left pectoral-fin of Lophiomus spp. collected in this study for visualizing interspecific variations in pectoral-fin ray counts. A. Lm. setigerus (Vahl, 1797), neotype (NTUM10408, sample ID: WJC0905). B. Lm. laticeps (Ogilby, 1910) stat. rev. (NTUM13463, sample ID: NC1375). C. Lm. immaculioralis sp. nov., holotype (NTUM16313, sample ID: WJC7777). D. Lm. nigriventris sp. nov., holotype (NTUM15096, sample ID: WJC5808). E. Lm. carusoi sp. nov., holotype (MNHN 2024-0099, sample ID: NC2059).

Fig. 16. Esca of Lophiomus spp. A. Lm. laticeps (Ogilby, 1910) stat. rev. (NTUM13463, sample ID: NC1375). B. Ditto (NTUM13468, sample ID: NC964). C. Lm. nigriventris sp. nov., holotype (NTUM15096, sample ID: WJC5808). D. Lm. immaculioralis sp. nov., holotype (NTUM16313, sample ID: WJC7777). E. Lm. carusoi sp. nov., holotype (MNHN 2024-0099, sample ID: NC2059). F. Ditto, paratype (NTUM17682, sample ID: NC1978).G. Lm. setigerus (Vahl, 1797) (NTUM14414, sample ID: WJC7223). H. Ditto (NTUM14414, sample ID: WJC7224). Scale bars = 1 mm.

Fig. 1. Bathymetric terrain map of eastern Indian Ocean and West Pacific showing the occurrence points of species of Lophiomus Gill, 1883 based on the samples/sequences included in the analyses of this study. White circle: type locality of the species of Lophiomus.