Schismatogobius tiola, Keith & Lord & Larson, 2017

Keith, Philippe, Lord, Clara & Larson, Helen K., 2017, Review of Schismatogobius (Gobiidae) from Papua New Guinea to Samoa, with description of seven new species, Cybium 41 (1), pp. 45-66 : 52-57

publication ID	https://doi.org/ 10.26028/cybium/2017-411-005
persistent identifier	https://treatment.plazi.org/id/2F75C925-CE49-FB26-FEDC-2F2329E8C9F3
treatment provided by	Felipe
scientific name	Schismatogobius tiola
status	sp. nov.

Treatment

Schismatogobius tiola View in CoL , new species

( Figs 1-2C View Figure 1 View Figure 2 , 4-5 View Figure 4 View Figure 5 ; Tabs I-III)

Material examined. – Seven specimens from Solomon Islands with a size range of 23.1-33.5 mm SL .

Holotype. – MNHN 2016-0265 About MNHN , male (25.5 mm SL); Poitete River , Kolombangara [= Kolobangara] Island, Solomon, 14 Nov. 2015, coll. Keith, Lord, Boseto and Marquet; tag 6914.

Paratypes. – MNHN 2016-0266 About MNHN , 2 females (28.2- 33.5 mm SL); Poitete River , Kolombangara Island, Solomon, 11 & 13 Nov. 2015, coll. Keith, Lord, Boseto and Marquet. QM I.40660, 1 female (25 mm SL); Vanga River , Kolombangara Island, Solomon, 18 Nov. 2015, coll. Keith, Lord, Boseto and Marquet ; tag 11927. MNHN 2016-0292 About MNHN , 1 male (23.1 mm SL); Maravari River , Vella Lavella Island, Solomon, 31 Oct. 2016, coll. Keith, Lord, Boseto and Hevalao ; tag 10635. MNHN 2016-0294 About MNHN , 1 female (26.9 mm SL); Mondo River, Ranongga Island , Solomon, 26 Oct. 2016, coll. Keith, Lord, Boseto and Hevalao ; tag 10587. MNHN 2016-0295 About MNHN , 1 female (29.8 mm SL); Poro River , Ranongga Island, Solomon, 23 Oct. 2016, coll. Keith, Lord, Boseto and Hevalao ; tag 13930.

Diagnosis

Usually 15 pectoral rays; pectoral fins with a large triangular dorsal (or transverse) black band and a smaller one posteriorly. First dorsal fin membrane posterior to spine 6 not connected to base of spine of second dorsal fin. Anal fin I,8-9. Ventral surface of head in male blackish with a white mentum. Ventral surface of head in female whitish or slightly pigmented with dusky blotches and with usually a blackish ring around mentum.

Description

A medium sized Schismatogobius (average size <29 mm SL). Body naked, slender, almost circular in cross-section. Head rounded, snout rather pointed, cheeks bulbous in male. Mouth oblique, tip of lower lip anteriormost. Jaw lengths in males much greater than in females; jaw length 48-55% of HL in male and 28-35% of HL in females. Lower jaw reaching vertical of 1/3 to 1/2 of the eye in female and exceeding (for half eye diameter) a vertical of posterior margin of eye in male. Eyes high on head, close together with interorbital width about equal to half eye diameter. Anterior nostril short and tube-like.

Dorsal fins VI-I,9, membrane in first dorsal fin posterior to spine 6 not connected to base of spine of second dorsal fin. D1 with all spines about equal in length. Anal fin I,8(2)- I,9(5), slightly behind or approximately below second dorsal fin origin. Caudal fin with 11-12 branched rays, posterior margin rounded. Pectoral fins oblong with posterior margin pointed and 14(1)-15(6) rays ( Tab. I), ventralmost ray unbranched. Pelvic fins always I,5, with both fins joined together for their entire length between fifth rays to form a strong cup-like disc and a well developed and lobed frenum between spines, fins not extending beyond anus. Morphomeristic data given in table III.

Tongue (anterior tip) bilobed. Teeth in upper jaw (15- 20) usually in two rows, teeth conical and slightly recurved. Teeth in lower jaw (6-13) usually in one or two rows anteriorly and single row laterally, all teeth conical with outer row teeth only slightly enlarged and somewhat recurved.

Cephalic sensory pore system always with pores B, D, F, K, L, N and O, pore D singular with all other pores paired; oculoscapular canal absent between pores F and K. Anterior interorbital extension of anterior oculoscapular canal with double terminal pores B slightly posterior to posterior nostril. D pore at rear of interorbital. Posterior extension of anterior oculoscapular canal terminating laterally on each side of head at pore F, just behind posterior edge of eye. Posterior oculoscapular canal with 2 terminal pores, K and L; preopercular canal with 2 pores, N and O. Cutaneous sensory 20 0.47 papillae not well developed and inconspicuous due to 19 0.16 0.63 preservation Sexual dimorphism. fairly well developed with 18 10.85 10.69 10.85 male having jaws longer than females and a different colour pattern on ventral surface of head. Urogenital 17 0 10.85 10.69 10.85 papilla broadly rounded in females and slightly point- 16 16.12 16.12 17.06 16.9 17.22 ed Colour in males in preservation. ( Fig. 5C View Figure 5 ) 15 0.71 16.04 16.04 17.3 17.14 17.45 Usually four vertical black bands in dorsal view;

first band below first dorsal fin, second and third 15.25 15.09 18.08 18.08 18.24 14 18.4 18.4 bands below second dorsal fin and fourth band at hypural crease. Lateral body colour markings varia- 13 0.16 15.25 15.09 18.08 18.08 18.24 18.08 18.24 ble with individual patterns of marbled brown to grey 12 17.77 17.77 15.41 15.64 18.87 18.87 18.55 18.4 18.71 to in black lateral. Head view. dusky In male, darker, ventral dorsally surface than of head ventrally and 11 0.16 17.92 17.92 15.25 15.49 18.71 18.71 18.55 18.4 18.71 frenum Ventral surface mostly black of head, with in female white mentum whitish or (Fig slightly. 2C). individuals). 8 9 10 0.16 0.47 0.31 0.31 0.16 17.92 18.08 17.92 18.08 15.25 15.41 15.49 15.64 18.71 18.55 18.71 18.55 18.55 18.71 18.4 18.55 18.87 18.71 (a whitish pigmented Fig more. 2C. or First), or less usually mostly dorsal white with fin brown isthmus with blackish with large; belly a ring black white around whitish median mentum mentum; breast band and paired 7 6.76 6.92 7.08 6.92 17.61 17.61 15.41 15.17 18.08 18.08 17.92 17.77 17.92 and with black a black margin median. Second band. Caudal dorsal fin fin black mostly and cream white, Schismatogobius 5 6 0 0 0 13.84 13.84 13.84 14.78 14.78 14.78 14.94 14.94 14.94 14.78 14.78 14.78 14.94 14.94 14.94 16.67 16.67 16.67 16.67 16.67 16.67 15.25 15.25 15.25 15.33 15.33 15.33 16.19 16.19 16.19 16.19 16.19 16.19 17.45 17.45 17.45 17.3 17.3 17.3 17.3 17.3 17.3 vic with black white pigmented disc black. spots mostly. blotch Base posteriorly whitish of at pectoral centre. over Anal of rays fin hypural fin white, mostly sometimes crease and cream distal and slightly. Pelpart two - between 4 3 15.09 15.09 15.09 16.19 18.4 18.55 18.4 18.24 19.18 19.18 16.51 16.82 16.35 16.35 16.35 16.19 16.19 Colour Four in vertical life (Fig black. 5A, B bands) in dorsal view, each divergence 2 0.31 0.62 0.31 15.09 15.09 15.09 15.09 15.09 15.09 16.35 16.67 18.71 19.03 18.87 19.18 19.03 18.71 18.55 18.87 19.5 19.18 19.5 19.18 16.19 16.51 16.51 16.82 16.51 16.82 16.51 16.82 16.82 16.51 16.67 16.35 16.67 16.35 band black female with band. In male. a Between bright, presence blue vertical of border bright black, both blue bands spots in, male orange on each and to of 1 0.00 0.31 0.31 15.09 15.09 15.09 16.35 18.71 18.87 18.71 18.55 19.18 19.18 16.51 16.82 16.51 16.51 16.51 16.35 16.35 rose rose with with many many large small blue blue spots spots.. Male Female head head orange darker to percentage)) Caledonia and Lower mottled half of, mostly the body black in lateral at nape view and between mottled, eyes with.

(matrix essi

) essi )) essi ))) mondo mondo New Caledonia tiola ) tiola )) tiola from black superior, with and half reddish of the body blotches. First, clearly dorsal fin different trans- distance 06948 Solomon 11939 Solomon Solomon 12065 11932 Solomon S. Solomon (Solomon (. S (Solomon S. S. Australia hoesi (6916 Solomon 6917 Solomon Vanuatu 1 2 Vanuatu S tuimanua (. S. ( tuimanua Solomon (. S Solomon (S. NC 28207 1 S New (Solomon S. Solomon S. (Solomon (S. gin dark lucent. Second spots with on large dorsal rays black. fin Caudal translucent median fin marbled band with and or rows barred black of small mar- with

06945 06946 12070 – Pairwise bruynisi bruynisi bruynisi bruynisi nsp 1 nsp 1 nsp 1 nsp 2 S vanuatuensis vanuatuensis vanuatuensis vanuatuensis nsp Samoa 21 nsp 22 Samoa 3 nsp 10585 10598 3 nsp fuligimentus fuligimentus 2 nsp 5483 6914 2 nsp 11927 2 nsp and black lucent two and. Pelvic large white white disc, with mostly spots black posteriorly whitish spot over at. hypural Anal rays fin. Frenum crease trans-. II S. S.. S. S S. S.. S S.. S. S. S. S S. S.. S. S S. S. S. . S S. mostly without markings. Pectoral fins whitish at the Table 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 base distal, with half. small orange and blue spots, and black on

Pectoral

;

rays

: Standard

Dorsal Pect-L

: SL

;

)

;

rays

% %

(

Pectoral depth length

: peduncle fin

Caudal

length

Caudal: standard: CFL

; CPD

) SL

;) %

(

% length percentages

(length fin as

Jaw Anal

given

: JL AFL

; are)

; SL)

(% Morphometrics length (length

. Head fin species: dorsal

;

)

SL Second

( Schismatogobius length: SDFL

;) Preanal SL

new

PAL (

seven; anus

)

the SL

at of

depth

(

length Body Morphomeristics

Predorsal BDa

;)

–:

SL. PDL %

III ( Schismatogobius tiola has been collected in freshwater

streams

with moderate to fast flow in shallow areas of rocks

and gravel

(depth

0.3-1 m) just

above

tidal

influence

with S

bruynisi and S. vanuatuensis , in the same habitat.

Etymology

The name for the new species, as a noun in apposition, is dedicated to Tiola, the protecting spirit of war canoes in the Solomon Islands legend of canoe building and their prow figurehead.

Remarks

In the story of Tiola, a stone dog protector of Nusa Roviana village, Tiola would turn its body to face the direction

of where

the village

should raid

in the direction

of incoming

warriors

In these

times

, people

did

not

know

how

make the tomako [war canoe]. But Tiola told the people how to make the tomako using certain materials. People wondered where they could find the power to

consecrate

the tomako

Tiola

told

them

make a

canoe

icon (nguzunguzu

)

and place it on

the bow of the canoe. The dog sat

down and

folded

its

legs and said ‘Like this’ ( Aswani, 2000). The nguzunguzu conferred upon them the power of Tiola. In this legend, Tiola is thought to come from Kolombangara, the type locality of the new species.

Affinities

S. tiola differs from the other species sequenced and present in the area studied by having a high% of divergence in COI gene (10.9- 18.9%) (Tab. II) and from these species, except S. bruynisi , S. essi n. sp., S. mondo n. sp. and S. baitabag n. sp., in having mostly 15 pectoral rays. It differs from S. bruynisi in having a small- er jaw length in male (14.1-14.3 vs 17.5-21.7% SL) and female (7.8-8.9% vs 11.1-12.6% SL), jaw length/head length ratio in male (48.5-55.4% vs 57.9-69.2%) and female (28.1-34.6% vs 42.5- 47.5%), and a different colour pattern of ventral surface of head and frenum in male and female ( Fig. 2B, C View Figure 2 ). It differs from S. essi in having a larger

size

(average adult size more than 26

mm SL

less), a smaller

anal fin length (

23.3-26.8% vs 26.8-33.3

% SL

)

, a greater caudal fin length (21.2-26% vs 16-19.8%

), and

different colour

pattern

ventral

surface

head,

pelvic disk

and

frenum

in male

and female

(

Fig

. 2

, C

)

SL), and a different colour pattern of ventral surface of head, pelvic disk and frenum in male and female

( Fig. 2C View Figure 2 ).

Distribution

S. tiola is known only from the Solomon Islands

( Fig. 4 View Figure 4 ).

Schismatogobius essi new species

( Figs 1-2B View Figure 1 View Figure 2 , 4 View Figure 4 , 6 View Figure 6 ; Tabs I-III)

Material examined. – Eleven specimens from

Solomon Islands with a size range of 18.2-26.3 mm

SL.

Holotype. – MNHN 2016-0267 About MNHN , male (20.1 mm

SL); Vage River, Kolombangara Island [= Kolobangara], Solomon, 11 Nov. 2015, coll. Keith, Lord,

Boseto and Marquet; tag 6945. Solomon, 10 Nov. 2015, coll. Keith, Lord, Boseto and Marquet; tag 12064. NTM 16447-002 View Materials , 1 female (18.2 mm SL); Erava River , Tetepare Island , Solomon, 12 Sep. 2006, coll. Jenkins and Boseto. QM I38030 , 1 female (22.3 mm SL), Tinahula River , Guadalcanal, Solomon Islands, Jul. 2006, coll. Smith. MNHN 2016-0296 About MNHN , 2 females (22.2-23.5 mm SL); Valakadju River , Vella Lavella Island , Solomon , 28 Oct. 2016, coll. Keith, Lord , Boseto and Hevalao; tags 10640 & 10639 .

Diagnosis

Usually 15 pectoral rays; pectoral fins with broad black triangular wedge dorsally usually with few rows of dark spots below it; dorsal fins VI-I,9, membrane in first dorsal fin posterior to spine 6 not connected to base of spine in second dorsal fin. Anal fin I,8-9. Ventral surface of head, frenum and pelvic disc in male entirely blackish or entirely brownish. In female, underside of head pale with chin and surrounding area blackish, with diffuse dark brown area on anterior part of branchiostegal membrane and isthmus.

Description

A small sized Schismatogobius (average size <21 mm SL). Body naked, slender, almost circular in cross-section.

Head rounded, snout rather pointed, cheeks bulbous in males. Mouth oblique, tip of lower lip anteriormost. Jaw lengths in males much greater than in females; jaw length 48-57% of HL in males and 31-34% of HL in females. Lower jaw reaching a vertical of anterior third of eye in female and reaching or exceed (for third of eye diameter) a vertical of posterior part of eye in male. Eyes high on head, close together with narrow interorbital, 9.2% of HL. Anterior nostril with short tube.

Dorsal fins VI-I,9, membrane in first dorsal fin posterior to spine 6 not connected to base of spine of second dorsal fin. D1 with all spines about equal in length. Anal fin I,8(2)- I,9(7), slightly behind or approximately below second dorsal fin origin. Caudal fin with 11-12 branched rays, posterior margin rounded. Pectoral fins oblong with posterior margin pointed and 14(2)-15(8)-16(1) rays ( Tab. I), ventralmost ray unbranched. Pelvic fins always I,5, with both fins joined together their entire length between rays 5 to form strong cup-like disc; a well developed frenum (small pointed lobe at each side) between spines, fins not extending beyond anus. Morphomeristic data given in table III.

Tongue (anterior tip) bilobed, not deeply. Teeth in upper jaw (12-23) usually in two rows, teeth conical and slightly recurved. Teeth in lower jaw (10-12) usually in one or two rows anteriorly and single row laterally, all teeth conical with outer row teeth only slightly enlarged and somewhat recurved.

Sexual dimorphism fairly well developed with males always having jaws longer than females and a different colour pattern on the ventral surface of head. Urogenital papilla broadly rounded in females and slightly triangular in males.

Colour in preservation ( Fig. 6 View Figure 6 )

Usually four vertical black bands over pale yellowish body in dorsal view; first band below first dorsal fin, second and third bands below the second dorsal fin (may coalesce to form single broad band, slightly paler toward centre) and fourth band at base of caudal fin. Side of body, between dark bands, with fine brown mottling and speckles, may form vermiculate patterns. Head slightly darker than body, side of head with darker brown mottling; indistinct darker brown bar from eye to jaw and another on opercle just behind rear preopercular margin; few small dark brown spots on middle of nape and another above corner of opercle. In male, ventral surface of head, frenum and pelvic disk entirely blackish or brownish ( Fig. 2B View Figure 2 ). In female, underside of head pale with chin and surrounding area blackish, with diffuse dark brown area on anterior part of branchiostegal membrane and isthmus, most of isthmus and breast unpigmented ( Fig. 2B View Figure 2 ). Belly pale anteriorly; posterior half of belly with brown pigment where black body bar extends. First dorsal fin with black basal band and black margin. Second dorsal fin translucent with several vertical blackish streaks and spots along rays. Caudal fin black and white, with broad black blotch (continuation of last body bar) extending in irregular pattern onto fin and becoming dusky posteriorly, partly surrounding two whitish spots posteriorly. Anal fin translucent to cream. Pectoral fins with broad black triangular wedge, with narrow black bar (formed by row of spots) ventrally and second short row of black spots posteriorly; a dark spot is generally visible on the posterior upper part.

Colour in life

Similar to that in preservation, but lateral and dorsal parts of body between vertical black bands reddish. First dorsal fin translucent with small black basal band and black margin. Second dorsal fin translucent with black stripes. Caudal fin black and white, with black blotch at hypural and two white spots posteriorly. Anal fin translucent. Pectoral fins with broad black triangular band or wedge commencing from dorsal part.