Ariosoma meeki (Jordan & Snyder, 1900)

Smith, David G., Ho, Hsuan-Ching, Huang, Jian-Fu & Chang, Yong-Hsu, 2018, The congrid eel genus Ariosoma in Taiwan (Anguilliformes: Congridae), with description of a new species, Zootaxa 4454 (1), pp. 84-106 : 98-101

Ariosoma meeki (Jordan & Snyder, 1900)

MEEk’S SHORT-TAIL CONgER ; 米克氏錐體糯鰻

FIgS. 9B , 10 ; TAbLE 2

Congrellus meeki Jordan & Snyder, 1900:347 (type locality: Tokyo Bay, Japan).

Ariosoma meeki ( Jordan & Snyder, 1900): Chen, 2004:31. Shao et al., 2008:239. Ho et al., 2015a: table 3. Ho et al., 2015b:144.

Anago anago (non Temminck & Schlegel, 1846): Chu, 1957:15. Lee & Yang, 1966:53, fig. 1. Chen & Weng, 1967:43. Lee, 1967:44. Chen, 1969: 132. Shen 1984:112. Chen & Yu, 1986:252. Shen, 1998a:8.

Ariosoma anago (non Temminck & Schlegel, 1846): Chen, 1956:76. Liang & Yeh, 1964:8.

Material examined. 84 SPEcIMENS, 121‒497 MM TL (^ MEAN SPEcIMENS MEASuRED) . CAS 15923 (1, 203), TAIWAN STRAIT, cA. 90 M, 16 JuN. 1981 . CAS 20760 (1, 324), TAIWAN STRAIT, 80‒100 M, 22 JuL. 1971 . CAS 30572 (1, 157), TAIWAN STRAIT, 19 JuL. 1973 . CAS 35144 (3, 132‒388), DONg-gANg, 7 JuL. 1973. CAS 49354 (2, 295‒348), TAIWAN, 1956 . CAS 224558 (1, 285), DAxI, 8 DEc. 2006. CAS-SU 21244 (6, 246‒281), KAOHSIuNg , 1906. ^NMMB-P1791 (1, 331), DAxI, 9 SEP. 2003. ^ NMMB-P2459 (1, 286), TAIWAN, NO DATE . ^ NMMB-P2517 (1, 298), WAN-LI-TONg, PINgTuNg, 15 SEP. 1966 . NMMB-P2936 (3, 161‒198), NO DATA. ^ NMMB-P3290 (10, 137‒309), NO DATA. ^NMMB- P3405 (17, 163‒497), PENgHu, 1 Aug. 1957 . ^ NMMB-P4134 (1, 343), PENgHu, 1 Aug. 1957 . ^ NMMB-P4140 (2, 429‒445), TAIcHuNg, 2 APR. 1962 . NMMB-P9022 (1, 129), PENgHu, 27 OcT. 2005 . ^NMMB-P11185 (3, 171-257), DONg-gANg, 15 DEc. 2010. ^NMMB-P11187 (2, 320‒321), DONg-gANg, 4 SEP. 2010. ^NMMB-P11905 (1, 380), NAN-fANg-AO, 6 SEP. 2010. ^NMMB-P11908 (1, 333), DONg-gANg, 16 JuN. 2009. ^NMMB-P14180 (1, 357), NANfANg-AO, 13 SEP. 2011. ^NMMB-P14205 (1, 279), DONg-gANg, 20 OcT. 2011. ^NMMB-P15564 (8, 159‒356), NO DATA. NMMB-P16140 (1, 286), NAN-fANg-AO, 9 JuL. 2010. ^NMMB-P17761 (3, 185‒267), DONg-gANg, 8 Aug. 2012. USNM 76655 (4, 195‒258), KAOHSIuNg, 3-4 DEc. 1914 . ^ USNM 192569 (2, 250‒302), PENgHu, 7 OcT. 1961 . USNM 273678 (1, 228), DAxI, 23 NOV. 1969. ^USNM 398512 (1, 286), DAxI, 6 NOV. 2009. ^ USNM 401978 (1, 332), TAIWAN, NO OTHER DATA . ^USNM 437333 (1, 232), KE-TSu-LIAO, 16 OcT. 2015. USNM 437334 (1, 121), DONggANg, 23 OcT. 2015. TENTATIVE IDENTIfIcATION. ASIZP 71041 (1, 353), TAIWAN, NO OTHER DATA . NMMB-P21748 (1, 248), PENgHu , TAIWAN STRAIT, 1 Aug. 1957 .

Diagnosis. ANuS NEAR MIDLENgTH. HEAD PORES REDucED IN SIzE AND NuMbER: INTERORbITAL, POSTORbITAL, AND SuPRATEMPORAL PORES AbSENT. TWO bLAck PATcHES AT POSTERIOR MARgIN Of EYE. DORSAL-fIN ORIgIN AbOVE OR SLIgHTLY IN fRONT Of PEcTORAL-fIN bASE; bROAD bLAck MARgINS ON VERTIcAL fINS. INTERMAxILLARY TOOTH PATcH SLIgHTLY uPTuRNED AT ITS ANTERIOR END; VOMERINE TEETH IN A SMALL TRIANguLAR PATcH, ITS LENgTH AbOuT 1/4 TO 1/3 Of THAT Of THE MAxILLARY TOOTH ROW. PREANAL VERTEbRAE 54‒66, PREcAuDAL VERTEbRAE 76‒89, AND TOTAL VERTEbRAE 144‒158.

Description. BODY STOuT, ANuS NEAR MIDLENgTH, DORSAL-fIN ORIgIN WELL bEfORE gILL OPENINg. JAWS SMALL, uPPER jAW PROjEcTINg SLIgHTLY bEYOND TIP Of LOWER jAW, INTERMAxILLARY TEETH PARTLY cONcEALED WHEN MOuTH cLOSED. EYE WELL DEVELOPED, MIDDLE Of EYE OVER RIcTuS. SNOuT bLuNT AND SHORT.

HEAD PORES SMALL. SO cANAL WITH 4 PORES; THE fIRST (ETHMOIDAL PORE) VERY SMALL, ON VENTRAL SIDE Of TIP Of SNOuT, juST bEfORE LIP; THE SEcOND SMALL AND IMMEDIATELY IN fRONT Of AND AbOVE ANTERIOR NOSTRIL; THE THIRD ON DORSAL SuRfAcE Of SNOuT AbOVE ANTERIOR NOSTRIL; fOuRTH AbOVE AND SLIgHTLY bEHIND POSTERIOR NOSTRIL AT AbOuT MID-EYE LEVEL; fIfTH AND SIxTH AbSENT. IO cANAL WITH 5 OR 6 PORES; THE fIRST RIgHT bEHIND ANTERIOR NOSTRIL; SEcOND ON uPPER LIP AbOVE fLANgE, bELOW OR SLIgHTLY bEHIND POSTERIOR NOSTRIL; THIRD bELOW ANTERIOR MARgIN Of EYE; fOuRTH AbOVE RIcTuS SLIgHTLY bEHIND MIDDLE Of EYE; fIfTH bEHIND RIcTuS AT LEVEL Of POSTERIOR MARgIN Of EYE; 0 OR 1 IN AScENDINg bRANcH Of cANAL bEHIND EYE. POM PORES 10; 7 IN MANDIbuLAR SEcTION, INcLuDINg 1 bEHIND RIcTuS; 3 IN PREOPERcuLAR SEcTION, IN A LONgITuDINAL ROW. NO ST PORE.

TEETH SMALL, cONIcAL, MuLTISERIAL; MAxILLARY AND INTERMAxILLARY TEETH cONTINuOuS; INTERMAxILLARY TOOTH PATcH SLIgHTLY uPTuRNED AT ANTERIOR END; VOMERINE TEETH STOuT OR bLuNT, fORMINg A NARROW ELONgATE PATcH ENDINg bEHIND MIDPOINT Of MAxILLARY TOOTH PATcH.

BODY uNIfORMLY WHITISH OR YELLOWISH gRAY, SLIgHTLY PALER VENTRALLY, DORSAL AND ANAL fINS WITH A VERY THIN bLAck MARgIN. HEAD AND SNOuT EITHER LIgHT cOLOR OR WITH INDISTINcT bANDS; TWO DARk PATcHES bEHIND POSTERODORSAL AND POSTEROVENTRAL PART Of EYE.

Remarks. Ariosoma meeki cAN bE EASILY DISTINguISHED fROM OTHER cONgENERS IN TAIWAN bY HAVINg TWO bLAck PATcHES AT THE POSTERIOR MARgIN Of THE EYE AND bY LAckINg PORES bEHIND AND bETWEEN THE EYES AND IN THE SuPRATEMPORAL cANAL. THE cOLOR Of THE PEcTORAL fIN SHOWS gREAT VARIATION, fROM PINkISH TO ENTIRELY bLAck. THE PORES ON THE HEAD AND LATERAL LINE ARE gENERALLY SMALLER THAN THOSE Of OTHER cONgENERS. THE HEAD IS gENERALLY STOuTER THAN THAT Of OTHER cONgENERS.

TWO SPEcIMENS (ASIZP 71041, NMMB-P21748) APPEARED LESS SIMILAR TO A. meeki . THE OVERALL APPEARANcE IS SIMILAR TO A. meeki , HOWEVER, THERE ARE SLIgHTLY MORE PORES ON THE HEAD, WITH 3+0 OR 3+1 SO PORES; IO WITH 1‒4 PORES bEHIND THE EYE; 0‒2 PREOPERcuLAR PORES; AND 0 OR 3 SMALL ST PORES. THERE ARE TWO INDISTINcT bLAck PATcHES AT THE POSTERIOR MARgIN Of THE EYE, ONE AbOVE AND ONE bELOW, buT NOT AS cLEAR AS IN THE OTHER SPEcIMENS . THE DORSAL fIN HAS A bROAD bLAck MARgIN AND THE ANAL fIN A THIN bLAck MARgIN. THESE SHOuLD PRObAbLY bE TREATED SEPARATELY.

UNPubLISHED gENETIc DATA REVEAL TWO cLADES IN TAIWAN. ONE Of THESE cLADES cONSISTS ONLY Of LARVAE, HOWEVER, AND WE cANNOT cOMPARE AND EVALuATE THE TWO cLADES uNTIL WE HAVE MORPHOLOgIcAL DATA ON ADuLTS Of bOTH. THE WIDE RANgE Of VERTEbRAL cOuNTS ALSO SuggESTS THE PRESENcE Of TWO SPEcIES. Ariosoma meeki NEEDS TO bE STuDIED OVER ITS ENTIRE RANgE, WHIcH ExTENDS fROM JAPAN TO AuSTRALIA, TO RESOLVE THE THE TAxONOMY.

IN SOME cHARAcTERS, Ariosoma meeki STANDS APART fROM THE OTHER SPEcIES AND APPROAcHES THE cONDITION IN Bathymyrus AND Parabathymyrus . THE REDucTION IN bOTH THE SIzE AND NuMbER Of HEAD PORES REfLEcTS THIS, AS DOES THE SLIgHTLY uPTuRNED INTERMAxILLARY TOOTH PATcH. THERE ARE OTHER SPEcIES THAT PARTIALLY bRIDgE THE gAP, HOWEVER, AND IT IS DIffIcuLT TO fIND A cLEAR DIVIDINg LINE. A cOMPLETE ANALYSIS Of cHARAcTERS MAY WARRANT SEPARATE gENERIc STATuS fOR Ariosoma meeki , buT WE LEAVE THAT fOR fuTuRE STuDIES.

Figures

FIGURE 9. UPPEr-jaW TEETH Of Ariosoma SPEcIES. A. A. majus. B. A. meeki. C. A. megalops, NMMB-P12306. D. A. shiroanago, NMMB-P17984. NOT TO ScaLE.

FIGURE 10. Ariosoma meeki (Jordan & Snyder, 1900), NMMB-P23593, 233 mm TL.