63
Sillago pe sica sp. no ., a new sillaginid (Pe ci o mes, Sillaginidae)
om he Pe sian Gul
Hashem Khandan Ba ani1,2 , Mohammad Sadegh Ala i-Yeganeh2, Mehdi Ghanba i a di3
1 Depa men o Aqua ic sciences, Hamoun In e na ional We land Ins i u e, Resea ch Ins i u e o Zabol, Zabol, I an
2 Depa men o Ma ine Biology, Facul y o Na u al Resou ces and Ma ine Silences, Ta bia Moda es Uni e si y, Nu , I an
3 Depa men o Biology, Facul y o Science, Uni e si y o Sis an and Baluches an, Zahedan, I an
Co esponding au ho : Mohammad Sadegh Ala i-Yeganeh ([email p o ec ed])
Copy igh : © Hashem Khandan Ba ani e al.
This is an open access a icle dis ibu ed unde
e ms o he C ea i e Commons A ibu ion
License (A ibu ion 4.0 In e na ional – CC BY 4.0).
Resea ch A icle
Abs ac
A new species o sillaginid ish, Sillago pe sica sp. no ., is desc ibed om 30 specimens
collec ed along he sou he n coas o he Pe sian Gul (Bushe ), I an. Mo phological
compa isons wi h 15 congene ic species, including membe s o he S. sihama com-
plex, show ha S. pe sica closely esembles S. sihama in me is ic coun s and colo -
a ion bu is clea ly dis inguished by a unique swim bladde mo phology. The pos e i-
o sub-ex ensions o he an e ola e al swim bladde ex ensions in S. pe sica display
a complex s uc u e comp ising i e b oad ex ensions connec ed o he swim bladde
body, a ea u e absen in S. sihama and o he sillaginids. Addi ional diagnos ic cha -
ac e s include dis inc me is ic, mo phome ic, and colo a ion ai s. Molecula analy-
ses o mi ochond ial cy och ome c oxidase subuni I (COI) sequences co obo a e his
species’ dis inc i eness, wi h phylogene ic econs uc ion placing S. pe sica haplo ypes
and a p e iously ecognized G5 clade haplo ype o he S. sihama complex in a s ongly
suppo ed monophyle ic clade sis e o S. indica and S. suezensis. In aspeci ic gene ic
di e gence wi hin haplo ypes o silaginid species and clades o S. sihma anged om
0.00 o 0.01 (K2P). The S. pe sica haplo ypes ma ched he G5 clade o S. sihama (0.01,
K2P dis ance) whe eas i exhibi ed 0.18–0.24 K2P di e gence om haplo ypes o o he
sillaginid species and clades o he S. sihama complex. A de ailed mo phological de-
sc ip ion is p o ided along wi h diagnos ic illus a ions.
Key wo ds: New species, sillaginids, Sillago pe sica, axonomy
In oduc ion
Membe s o he amily Sillaginidae Richa dson, 1846 a e widely dis ibu ed in
insho e wa e s cha ac e ized by sandy subs a es and es ua ine en i onmen s
h oughou he Indo-Wes Paci ic egion (McKay 1992). Commonly known as sand
whi ings o sand bo e s, hese small o medium-sized deme sal ma ine ishes a e
o conside able comme cial and ec ea ional impo ance h oughou hei ange
(McKay 1992; G ay and Kennelly 2003). Cu en ly, i e gene a, Sillago Cu ie , 1816,
Sillaginopodys Fowle , 1933, Sillaginops Kaga, 2013, Sillaginopsis Gill, 1861, and
Sillaginodes Gill, 1861, comp ising 39 alid species a e ecognized wi hin he am-
ily (Saha e al. 2024). Recen axonomic e o s ha e expanded knowledge o his
Academic edi o : Tihomi S e ano
Recei ed:
16 June 2025
Accep ed:
13 Augus 2025
Published:
9 Oc obe 2025
ZooBank: h ps://zoobank.o g/
DF86BF9A-A7F9-4C4E-BF36-
07831E80D136
Ci a ion: Ba ani HK, Ala i-Yeganeh MS,
Ghanba i a di M (2025) Sillago pe sica
sp. no ., a new sillaginid (Pe ci o mes,
Sillaginidae) om he Pe sian Gul .
ZooKeys 1255: 63–76. h ps://doi.
o g/10.3897/zookeys.1255.162247
ZooKeys 1255: 63–76 (2025)
DOI: 10.3897/zookeys.1255.162247
64
ZooKeys 1255: 63–76 (2025), DOI: 10.3897/zookeys.1255.162247
Hashem Khandan Ba ani e al.: Sillago pe sica, a new species om he Pe sian Gul
g oup h ough he desc ip ion o new species and e ision o hei geog aphic dis-
ibu ions (Cheng e al. 2021; Saha e al. 2022; Yu e al. 2022). No ably, ou ecen -
ly desc ibed species, Sillago nig o ascia a Xiao e al., 2021, Sillago pa asihama Yu
e al., 2022, Sillago muk ijoddhai Saha e al., 2022, and Sillago mengjialensis Saha
e al., 2022, we e p e iously misiden i ied as S. sihama (Xiao e al. 2021; Saha e
al. 2022; Yu e al. 2022). Sillago sihama is he mos ex ensi ely sampled species
in he amily and li es in di e se habi a s ac oss he Indo-Wes Paci ic; howe e , i
is known o be a c yp ic species complex (Cheng e al. 2021).
Species iden i ica ion wi hin he amily Sillaginidae is o en challenging due
o he highly simila ex e nal mo phological cha ac e s. This has led o he mis-
iden i ica ion o biologically dis inc species and he synonymiza ion o alid
axa unde widesp ead species (K ück e al. 2013). Among diagnos ic cha ac-
e s, he mo phology o he swim bladde is especially use ul o dis inguishing
sillaginid species. Based on swim bladde s uc u e, McKay (1985) p oposed
h ee subgene a wi hin he genus Sillago: Sillaginopodys Fowle , 1933, cha ac-
e ized by a educed swim bladde lacking a duc -like p ocess; Sillago Cu i-
e , 1817 wi h wo ape ing pos e io ex ensions and a duc -like p ocess; and
Pa asillago McKay, 1985, which exhibi s a swim bladde wi h a single pos e io
ex ension and a duc -like p ocess. While his subgene ic classi ica ion aids in
he axonomy and phylogene ic analysis o Sillago, he simila i y o swim blad-
de mo phology among some closely ela ed species (e.g. S. sihama and S.
shaoi) complica es species-le el iden i ica ion, necessi a ing he use o addi-
ional mo phological o molecula e idence.
DNA ba coding has been inc easingly applied o apid and accu a e spe-
cies iden i ica ion and disco e y o c yp ic species wi hin a ious ish g oups,
including sillaginids (Cheng e al. 2021; Xiao e al. 2021; Mul aney e al. 2023).
No ably, Cheng e al. (2021) iden i ied eigh c yp ic lineages wi hin he S. si-
hama complex ac oss he Indo-Wes Paci ic egion by in eg a ing pheno ypic
ai s wi h molecula da a, including m DNA gene agmen s (12S, 16S, COI,
Cy b) and a nuclea gene agmen (Rag2). In addi ion, he phylogene ic place-
men o he Sillaginopodys chond opus haplo ype wi hin Sillago haplo ypes in
his s udy highligh s he impo ance o a comp ehensi e axonomic app oach
ha combines de ailed mo phological examina ion wi h molecula analyses o
esol e species bounda ies and axonomic issues in sillaginids. In he p esen
s udy, we desc ibe a new Sillago species om he Pe sian Gul coas , based on
an in eg a i e app oach ha includes mo phome ic and me is ic cha ac e s,
swim bladde mo phology, e eb al coun s, and mi ochond ial cy och ome
c oxidase subuni I (COI) gene sequences.
Ma e ials and me hods
Sampling
Specimens o he newly desc ibed species we e ob ained di ec ly om lo-
cal ishe men and h ough ishe y su eys conduc ed along he coas o
Busheh ci y in he no he n Pe sian Gul , I an (Fig. 1). The holo ype and
pa a ype specimens ha e been deposi ed in he Aqua ic Animals collec ion
a he Depa men o Ma ine Biology, Ta bia Moda es Uni e si y, Nu , I an
(TAC1245F and TAC1246F).
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ZooKeys 1255: 63–76 (2025), DOI: 10.3897/zookeys.1255.162247
Hashem Khandan Ba ani e al.: Sillago pe sica, a new species om he Pe sian Gul
Mo phological analysis
The genus and species classi ica ion ollows McKay (1985, 1992). Te minology
o he appendages o he swim bladde adhe es o he desc ip ions p o ided
by Shao e al. (1986), Kaga and Ho (2012), and Cheng e al. (2021). Gill ake s
and swim bladde s we e examined in he dissec ed pa a ypes. The iden i ica-
ion o a ious e eb ae was based on he desc ip ions by McKay (1992). In
addi ion o he swim bladde and e eb ae, 10 me is ic and 17 mo phome ic
cha ac e s we e analyzed, along wi h desc ip i e ai s such as body and in col-
o a ion. All measu emen s we e aken wi h dial calipe s o he nea es 0.1 mm.
S anda d leng h (SL) and head leng h (HL) a e abb e ia ed acco dingly.
Gene ic analysis
Mi ochond ial DNA (m DNA) cy och ome oxidase subuni I (COI) agmen s
we e ampli ied using he p ime s FishF1: 5′-TCAACCAACCACAAAGACATTG-
GCAC-3′ and FishR1: 5′-TAGACTTCTGGGTGGCCAAAGAATCA-3′ (Wa d e al.
2005). A polyme ase chain eac ion (PCR) was conduc ed acco ding o he p o-
ocols es ablished by Gao e al. (2011).
The cleaned DNA unde wen sequencing in a cycle sequencing eac ion.
Sequences we e hen assembled, aligned, and edi ed using BIOEDIT . 7.0.4
and MAFFT . 7. The nine COI sequences ob ained o his esea ch ha e
been deposi ed in GenBank wi h accession numbe s PV523932–PV523934
(S. sihama), PV524004, PV524005 (S. a abica), PV524006 (S. a enua a), and
PV524007–PV524009 (S. pe sica). An addi ional 63 sequences om he Sillag-
inidae we e downloaded om GenBank (Fig. 4) including haplo ypes ep esen -
ing eigh clades o he S. sihama complex (Cheng e al. 2021). This was done
o c ea e a comp ehensi e da ase o e alua ing he phylogene ic posi ion o
he new sequences in his s udy and o econs uc ing he phylogene ic ela-
ionships among ep esen a i es o he Sillaginidae. Acco ding o Cheng e al.
(2021), wo haplo ypes om Te apon ja bua we e selec ed as he ou g oup.
Figu e 1. Sampling si e o Sillago pe sica in he Pe sian Gul .
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ZooKeys 1255: 63–76 (2025), DOI: 10.3897/zookeys.1255.162247
Hashem Khandan Ba ani e al.: Sillago pe sica, a new species om he Pe sian Gul
The ini ial phylogene ic analysis was conduc ed using he maximum-likeli-
hood (ML) me hod h ough IQ-TREE . 1.6.12 (Nguyen e al. 2015). To assess
b anch suppo , we employed he UFboo 2 boo s ap es wi h 10,000 eplica es
(Hoang e al. 2018). The e olu iona y model TPM2+F+I+G4 was iden i ied as he
bes - i model using Model Finde (Kalyaanamoo hy e al. 2017) based on he
Bayesian in o ma ion c i e ion. Gene ic dis ances among he sequences we e
calcula ed using he Kimu a 2-pa ame e (K2P) dis ance model in MEGA 7. The
esul ing ML ee was isualized using FIGTREE . 1.4.3. Bayesian-in e ence (BI)
analysis was pe o med in MRBAYES . 3.2.7 using wo independen Ma ko
Chain Mon e Ca lo chains o 50,000,000 gene a ions, wi h he i s 25% o ees
disca ded as bu n-in. The emaining ees we e combined o p oduce a 50% ma-
jo i y- ule consensus ee. Pos e io p obabili ies o each clade we e calcula ed
om BI, wi h alues exceeding 0.95 conside ed signi ican suppo . Es ima es o
e olu iona y di e gence among sillaginid species we e de i ed using he Kimu a
2-pa ame e (K2P) model implemen ed in MEGA 11 (Tamu a e al. 2021).
To delinea e species, we applied h ee molecula species delimi a ion me h-
ods: (a) wo dis ance-based me hods, Au oma ic Ba code Gap Disco e y
(ABGD) and Assemble Species by Au oma ic Pa i ioning (ASAP); and (b) a
opology-based me hod, Bayesian Poisson T ee P ocess (bPTP). The COI se-
quence da ase was analyzed on he ABGD webse e h ps://bioin o.mnhn. /
abi/public/abgd/abgdweb.h ml wi h a combina ion o se ings in he pa ame-
e ange o Pmin = 0.001, Pmax = 0.1, and gap wid h = 0.1–0.9, ac oss a o al
o 10 s eps, applying a K2P-co ec ed gene ic dis ance ma ix. Fo ASAP, he
pa i ion sco e in eg a es wo me ics: ba code gap wid h and he p obabili y o
panmixia (p- alue), whe e a lowe sco e indica es a mo e op imal pa i ion. This
me hod was execu ed using websi e h ps://bioin o.mnhn. /abi/public/asap/
asapweb.h ml wi h he Kimu a (K80) model.
Resul s
Taxonomic accoun
Family Sillaginidae Richa dson, 1846
Genus Sillago Cu ie , 1817
Sillago pe sica, sp. no .
h ps://zoobank.o g/18029739-2FD6-4E76-8669-3DC17FBF6C05
Fig. 2, Table 1
Type ma e ial. Holo ype: • TAC1245F; 165 mm SL; sex unknown sex; I an, Busheh
P o ince; 28°54'N, 50°46'E; Hashem Khandan Ba ani leg.; Decembe 2021.
Pa a ypes: • TAC1246F; 30 specimens, 114–195 mm TL, weigh 11.6–35.9 g;
I an, Busheh P o ince; loca ed in he no he n Pe sian Gul , I an; Hashem Khan-
dan Ba ani leg.; Decembe 2021.
E ymology. The species name pe sica is de i ed om he Pe sian Gul , whe e
he ype specimens we e collec ed.
Diagnosis. Do sal in wi h XI, I+21–22 ays and anal wi h II (23–24) ays. The
la e al line wi h 65–76 scales, 4–5 scale ows be ween he do sal- in o igin
and he la e al line. Gill ake s wi h 3+7–8 on he i s gill a ch. The e eb al
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ZooKeys 1255: 63–76 (2025), DOI: 10.3897/zookeys.1255.162247
Hashem Khandan Ba ani e al.: Sillago pe sica, a new species om he Pe sian Gul
o mula wi h 14 o 15 abdominal e eb ae (p edominan ly 14), 4–5 p edo sal
e eb ae (mos ly 4), and 14–15 caudal e eb ae (mos ly 14), esul ing in a o-
al e eb al coun o 32–34 (mos ly 32) (Table 1). The body is cha ac e ized by
he absence o da k blo ches o a mid-la e al s ipe. The swim bladde ea u es
wo pos e io ex ensions, wi h a duc -like p ocess o igina ing om he an e-
io end o he swim bladde and beginning a he junc ion o he oo s o he
wo pos e io ex ensions (Fig. 3). Fi e wide ex ensions connec he pos e io
sub-ex ensions o he an e ola e al ex ensions o he body o he swim bladde .
Desc ip ion. Gene al body ea u es a e illus a ed in Fig. 2, and coun s and
measu emen s a e p o ided in Table 1. The body is elonga e, sligh ly conical
a he an e io end, and ubula owa ds he pos e io end. The body dep h is
14.9 mm, 16.83% o SL. The head is la ge, and i s leng h is 26.3–28.7% o SL.
The snou is long, and i s leng h is 38.2–45.8% o HL. The eye is o mode a e
size, and i s diame e is 15.3–17.6% o HL. The in e o bi al egion is la , and
i s wid h is 17.9–21.1% o HL. The mou h is small, e minal, and he ips o
he uppe and lowe jaws a e almos equal in leng h. Bo h jaws ha e a se-
ies o e y small ee h ha which o m a b oad band ha ape s pos e io ly
in o a single ow. Gill ake s on he i s a ch a e poin ed and ela i ely la ge.
The caudal peduncle is sho ; i s dep h is 77.5–90.1% o he caudal-peduncle
leng h. The body is co e ed in small o mode a e-sized c enoid scales, while
he cheeks a e co e ed in cycloid scales. The la e al line begins abo e he
gill ape u e and he an e io po ion o he pec o al in, ex ending along he
do sal edge o he end o he body.
The species has wo sepa a e do sal ins, wi h ays as XI, I+21 ( ange:
21–22), and he in memb ane has blu y black spo s. The anal in has II, 23
( ange: 23–24) ays. The pec o al in wi h 15 (15–16) ays. The pel ic ins a e
sepa a e, wide, and ha e I+5 ays, app oxima ely iangula and smalle han he
pec o al ins. The caudal in has 16–18 ays.
Figu e 2. Sillago pe sica, sp. no ., holo ype (TAC1245F), 165 mm SL, Pe sian Gul coas , I an.
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ZooKeys 1255: 63–76 (2025), DOI: 10.3897/zookeys.1255.162247
Hashem Khandan Ba ani e al.: Sillago pe sica, a new species om he Pe sian Gul
Colo o esh specimens: he uppe su ace o he head is b igh b own,
while he unk is also b igh b own, ansi ioning o sil e on he abdomen. The
body lacks s ipes, al hough he an e io hal o he en al side may exhibi
some da k pigmen a ion. The do sal ins a e hyaline, ea u ing small da k spo s
on he in memb ane. The pec o al and pel ic ins a e ligh yellowish hyaline; he
anal in is hyaline and ee o da k spo s, and he caudal in is yellowish dusky,
wi h a black ma gin along he pos e io edge.
Swim bladde : he swim bladde is la ge and ea u es wo an e io ex en-
sions ha ex end o wa d o he basioccipi al, which is posi ioned abo e he
audi o y capsules on bo h sides. Addi ionally, i has wo pos e io ape ing
ex ensions ha each in o he caudal egion wi hou a lacuna be ween hem.
Two an e ola e al ex ensions a ise om he an e io po ion o he swim
Table 1. Mo phome ic measu emen s and coun s o Sillago pe sica.
Me is ic and Mo phome ic Measu emen s (mm) Sillago pe sica
Holo ype Pa a ypes (n = 40)
To al weigh (g) 30.81 11.63–31.94
To al leng h 165 114–175
S anda d leng h 145 101–154
Head leng h 41 29–43
Snou leng h 18 11–19
Eye diame e 7 6–8
In e o bi al wid h 8 5–8
Pos o bi al leng h 19 11–20
Body dep h 23 17–24
Body wid h 18 14–20
Leng h o caudal peduncle 8.5 8–9
Dep h o caudal peduncle 96–10
Base o he 1s do sal- in 28 21–30
Base o he 2nd do sal- in 47 37–49
Base o he anal- in 50 39–54
Pec o al- in leng h 22 15–23
Pel ic- in leng h 18 14–19
Ve eb ae 32 32–34
Do sal- in ays XI, I + 21 XI, I + (21–22)
Pec o al- in ays 16 15–16
Pel ic- in ays I + 5 I + (5–6)
Anal- in ays II + 23 II + (23–24)
Caudal- in ays 16 16 (16–18)
Gill ake s on i s a ch 3 + 8 (3) + (7–8)
La e al line scales 71 65–76
Scales abo e/below la e al line 4/9 (4–5)/(9–10)
As % o SL
Body dep h 15.8 14.92–16.83
Head leng h 28.7 26.35–28.71
As % o HL
Eye diame e 17.07 15.38–21.95
In e o bi al wid h 19.5 17.24–20.59
Snou leng h 43.9 37.93–44.19
Pos o bi al leng h (PL) 46.3 37.93–50.12
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Hashem Khandan Ba ani e al.: Sillago pe sica, a new species om he Pe sian Gul
Figu e 3. Swim bladde s o 13 Sillago species wi h wo pos e io ex ensions. Red a ow indica ed o i e ex ensions connec
he pos e io sub-ex ensions o he an e ola e al ex ensions o he body o swim bladde . A. S. pe sica sp. no .; B. S. sihama;
C. S. mengjialensis; D. S. muk ijoddhai; E. S. shaoi; F. S. nig o ascia a; G. S. indica; H. S. pa isquamis; I. S. in e medius; J. S.
caudicula; K. S. suezensis; L. S. sinica; M. S. pa asihama (Sou ces: Cheng e al. 2021; Saha e al. 2024).
bladde , each bi u ca ing in o an e io and pos e io sub-ex ensions. The an-
e io sub-ex ension consis s o a sho , simple, blind ubule, while he pos-
e io sub-ex ensions a e kinked, long, and complex a he beginning, becom-
ing simple and ela i ely hinne as hey ex end along he abdominal wall,
ul ima ely e mina ing a he base o he pos e io ex ensions. No ably, i e
wide ex ensions connec o hese wo sub-ex ensions, a ea u e ha is no
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Hashem Khandan Ba ani e al.: Sillago pe sica, a new species om he Pe sian Gul
obse ed in o he species wi hin his genus. Fu he mo e, a single duc -like
p ocess o igina es om he pel ic su ace o he swim bladde , ex ending
o he u ogeni al opening. This duc -like p ocess o igina es a he junc ion
o he oo s o he wo pos e io ex ensions, loca ed an e io o he e minus
o he swim bladde .
Dis ibu ion. In his s udy, specimens o S. pe sica we e collec ed om he
no he n Pe sian Gul coas o I an (Busheh ) (Fig. 1). The iden i ied haplo ypes
o med a monophyle ic g oup alongside he haplo ypes o he G5 clade o
S. sihama, which we e collec ed om he coas o Ka achi, Pakis an (Cheng e
al. 2021). Thus, he known dis ibu ion o his species ex ends om he no h-
e n coas o he Pe sian Gul o he no he n coas o he A abian Sea.
Compa ison. Acco ding o he subgene a g ading sys em o he genus
Sillago p oposed by McKay (1985), S. pe sica is classi ied wi hin he subge-
nus Sillago (Sillago) due o he p esence o wo pos e io ex ensions o he
swim bladde . This s udy alida es he ecogni ion o S. pe sica as a new
species h ough compa isons wi h all species in his genus. Dis inc ions
among hese species can p ima ily be made based on he me is ic and mo -
phome ic cha ac e s ou lined in Table 2. The new species is immedia ely
dis inguished om o he s by below se e al key cha ac e s: i has a smalle
head han S. megacephalus (26.35–28.71% SL s 33%). I has mo e b anched
anal in ays han S. pa asihama, S. shaoi, S. muk ijoddhai, S. nig o ascia a,
and S. suezensis (23–24 s 19–21). I has ewe scale ows be ween he la -
e al line and do sal- in o igin han S. in e medius (4–5 s 6–7) and a smalle
head (26.3–28.71% SL s 30.0–31.0%). I has ewe la e al line scales han
S. pa isquamis (65–76 s 79–84). I has ewe ans e sal scale ows han
S. pa isquamis (4–5/8–10 s 7/11–12). I has ewe a o al o e eb ae han
S. shaoi, S. pa isquamis, S. caudicula, and S. sinica (32–34 s 35–40).
A compa ison o swim bladde cha ac e is ics, a key ai o species di-
agnosis wi hin his amily, e ealed ha he swim bladde o S. pe sica is
e y simila o ha o S. sihama, S. nig o ascia a, S. shaoi, S. muk ijoddhai,
and S. mengjialensis. Howe e , no able di e ences exis . In S. shaoi and
S. muk ijoddhai, he oo s o he wo pos e io ex ensions a e non-adjacen ,
wi h a lacuna p esen be ween hem, whe eas in S. pe sica, S. nig o ascia a,
S. mengjialensis, and S. sihama, he oo s o he wo pos e io ex ensions
a e adjacen and lack a lacuna. Fu he mo e, he pos e io sub-ex ension
o he an e ola e al ex ensions in S. pe sica is dis inc i e, cha ac e ized by
a complex s uc u e a i s beginning, whe e i e wide ex ensions connec
o hese wo sub-ex ensions, a ea u e no obse ed in S. nig o ascia a,
S. mengjialensis, and S. sihama. Addi ionally, he o igin o he duc -like
p ocess in S. pe sica di e s om ha in S. pa asihama and S. indica. In
S. pe sica, he duc -like p ocess o igina es an e io o he e minus o he
swim bladde and be o e he junc ion o he oo s o he wo pos e io ex-
ensions. In con as , he duc -like p ocess in S. pa asihama and S. indica
o igina es a he e minus o he swim bladde and a ises a he junc ion o
he oo s o he wo pos e io ex ensions.
Fu he mo e, among he 12 known species o Sillago wi h wo pos e-
io ex ensions, S. pe sica can be easily dis inguished om S. caudicula
and S. in e medius based on body colo a ion, as bo h S. in e medius and
S. caudicula exhibi dusky black spo s on hei bodies. I can also be di e en i-
71
ZooKeys 1255: 63–76 (2025), DOI: 10.3897/zookeys.1255.162247
Hashem Khandan Ba ani e al.: Sillago pe sica, a new species om he Pe sian Gul
a ed om S. pa isquamis and S. sinica by he p esence o dusky spo s on he
second do sal- in memb anes, which show i e o six ows in S. pa isquamis
and h ee o ou ows in S. sinica. Addi ionally, S. pe sica can be empi ically
dis inguished om S. nig o ascia a, S. indica, and S. shaoi by he colo a ion
o he anal in: S. pe sica has a hyaline anal in wi hou black spo s, whe eas
S. nig o ascia a ypically has a yellowish anal in wi h spa se black spo s, and
S. indica and S. shaoi ha e yellowish-b own anal ins wi h black do s on he
in e adial memb anes. Mo eo e , S. indica, S. suezensis, and S. panhwa i pos-
sess a ain midla e al s ipe on hei bodies, which is no p esen in S. pe sica.
Gene ic analysis o he COI gene. Six y- h ee sequences om Sillago spe-
cies we e u ilized in he gene ic analysis. The gene ic dis ances among sil-
laginid species anged om 0.05 o 0.26 K2P, while he gene ic di e gences
wi hin known species we e be ween 0.00 and 0.01 K2P. The gene ic dis ance
be ween S. pe sica and o he ecognized Sillago species a ied om 0.18 o
0.024 K2P. In compa ison wi h he p e ious eigh clades o he S. sihama
complex, he gene ic dis ance o clade G5 was 0.01, while dis ances o he
o he eigh clades we e 0.18–0.20 (Table 3; Suppl. ma e ial 1). The Bayes-
ian and maximum-likelihood phylogene ic ee based on COI gene sequences
(Fig. 4) indica ed ha he h ee haplo ypes o S. pe sica and i e haplo ypes
om he S. sihama clade G5 (MF571946; Cheng e al. 2021) o med a mono-
phyle ic g oup. This clade is posi ioned as a sis e g oup o a clade consis ing
o h ee haplo ypes o S. indica and one haplo ype o S. suezensis. Addi ion-
ally, he h ee haplo ypes om specimens iden i ied as S. sihama in his s udy
(PV523932–PV523934) clus e ed in a monophyle ic g oup wi h hose om
S. sihama clade G1 (Cheng e al. 2021). The esul s om h ee species delim-
i a ion models (ASAP, ABGD, and bPTP) u he suppo he classi ica ion o
S. pe sica haplo ypes as a dis inc species.
Table 2. Compa ison o Sillago pe sica sp. no . and 15 o he species o Sillago wi h wo pos e io ex ensions o he swim
bladde . XI, I, 20–22.
Species Do sal- in ays Anal- in ays Pec o al- in
ays
Pel ic- in
ays
Scales in
la e al line
Scales abo e/
below la e al line
Gill ake s
i s a ch Ve eb ae HL/SL (%)
S. pe sicaaXI, I, 21–22 II, 23–24 15–16 I + (5–6) 65–76 4–5/9–10 3/7–8 32–34 26.35–28.71
S. malaba icabXI–XII, I, 21–24 II, 22–24 68–72 4–5/8–9.5 3–4/6–8 34 25–30.4
S. in e mediuscXI, I, 21–22 II, 21–22 67–70 6–7/8–9 - 34 30.0–31.0
S. megacephaluscXI, I, 22 II, 23 70 5/10–11 - - 33.0
S. panhwa idX–XII, I, 20–22 II, 18–23 69–84 4–5/7–10 3–4/7–8 34 27.9–35.0
S. shaoieXI, I, 20–22 II, 21–22 16–18 I + 5 70–73 5–6/10–12 3–4/5–6 35 26.1–31.0
S. pa isquamiscXII–XIII, I, 20–22 II, 22–24 79–84 7/11–12 1–2/7–9 39–40 25.9–27.7
S. sihamaeXI, I, 20–23 II, 21–23 68–72 5–6/10–12 3/8–9 34 24.0–30.0
S. caudicula XI, I, 22–23 II, 23–24 71 5/11 4/11 35–36 29.0–30.1
S. sinicagX–XI, I, 20–22 II, 21–23 75–79 5–6/9–11 2–4/6–8 37–39 24.7–29.8
S. suezensishX–XII, I, 19–22 II, 18–22 63–74 - 3–4/8–10 34 26.6–27.0
S. indicaiX–XI, I, 20–22 II, 21–23 68–71 5–6/10–12 3–4/7–8 33–35 27.5–32.4
S. muk ijoddhaijX–XI, I, 20–22 II, 21–23 15–18 I + 5 68–72 4–6/10–13 3–5/8–10 32–35 21.8–31.3
S. mengjialensisjXI, I, 20–22 II, 20–23 15–17 I + 5 66–72 4–5/10–12 3–4/8–10 31–35 25–31.7
S. nig o ascia akX–XII, I, 20–22 II, 20–22 14–16 I + 5 67–75 4–6/9–12 2–4/5–8 34–35 25.1–30.8
S. pa asihamalXI–XII, I, 18–21 II, 19–21 16–17 I + 5 65–70 4–5/8–10 2–3/5–7 34 18.4–29.0
No es: a, Тhis s udy; b, Di ya e al. 2021; c, McKay (1985, 1992); d, Panhwa e al. (2018); e, Xiao e al. (2016); , Kaga e al. (2010); g, Gao e al. (2011);
h, Golani e al. (2014); i, Kaga and Ho (2012); j, Saha e al. (2022); k, Xiao e al. (2021); l, Yu e al. (2022).
