Limnonectes nusantara, Gonggoli & Shimada & Matsui & Nishikawa & Sidik & Kadafi & Farajallah & Hamidy, 2025

Limnonectes nusantara sp. nov.

( Figs. 7–8 View FIGURE 7 View FIGURE 8 )

Limnonectes kuhlii “Lineage 4”: Matsui et al. (2016)

Holotype. Adult male (MZB Amph 33516) from Batubalay River , Lumpangi Village , Loksado District, Hulu Sungai Selatan Regency , South Kalimantan Province (Borneo), Indonesia at - 2.803344°S, 115.425771°E, elevation 177 m a.s.l., collected by Ade Damara Gonggoli, Adventus Robertino Rangin, and Ayibino on 9 January 2023. GoogleMaps

Paratypes (n = 16). Total of 14 specimens from Loksado District , Hulu Sungai Selatan Regency , South Kalimantan Province (Borneo), Indonesia : three adult females (MZB Amph 33522–24) from Pante River, Loksado Village at - 2.794351°S, 115.492750°E, elevation 270 m a.s.l., collected by Ade Damara Gonggoli, Adventus Robertino Rangin, and Ayibino on 10 January 2023 GoogleMaps ; two males (MZB Amph 33526, 28) and two females (MZB Amph 33527, 29) from Jaung River, Loksado Village at - 2.794682°S, 115.482456°E, elevation 226 m a.s.l., collected by Ade Damara Gonggoli, Adventus Robertino Rangin, and Ayibino on 11 January 2023 GoogleMaps ; two adult males (MZB Amph 25120, 22) from Loksado Village at - 2.799114°S, 115.485869°E, elevation 262 m a.s.l., collected by Irvan Sidik on 18 April 2008 GoogleMaps ; five adult females (MZB Amph 25110–11, 25291–92, 25405) from Malaris Village collected by Irvan Sidik in April 2008 .

One adult female (MZB Amph 15256) from Dusun Bancing Village , Paramasan District, Banjar Regency, South Kalimantan Province (Borneo), Indonesia at - 3.028892°S, 115.487781°E, elevation 527 m a.s.l., collected by Amir Hamidy and Abran Slamet on 17 February 2009 GoogleMaps . One adult male (MZB Amph 33520) collected with holotype GoogleMaps .

Referred specimens (n=12). Total of five specimens from Loksado District , Hulu Sungai Selatan Regency , South Kalimantan Province (Borneo), Indonesia : one adult male (MZB Amph 33536) and one adult female (KUHE 60952) from Malaris Village at - 2.804056°S, 115.506195°E, elevation 264 m a.s.l., collected by Tomohiko Shimada and Misbahul Munir on 19 September 2017 GoogleMaps ; one adult female (KUHE 60971) Loksado Village at one the way to Haratai Village, at - 2.782646°S, 115.511533°E, elevation 276 m a.s.l., collected by Tomohiko Shimada and Misbahul Munir on 20 September 2017 GoogleMaps ; two juveniles (MZB Amph 33521, 25) from Pante River, Loksado Village at - 2.794351°S, 115.492750°E, elevation 270 m a.s.l., collected by Ade Damara Gonggoli, Adventus Robertino Rangin, and Ayibino on 10 January 2023 GoogleMaps .

One juvenile (MZB Amph 15266) from Dusun Bancing Village , Paramasan District, Banjar Regency, South Kalimantan Province (Borneo), Indonesia at - 3.028892°S, 115.487781°E, elevation 527 m a.s.l., collected by Amir Hamidy and Abran Slamet on 17 February 2009 GoogleMaps .

Total of three specimens from Mt. Halau-halau , Batang Alai Timur District , Hulu Sungai Tengah Regency (Borneo) : one juvenile (KUHE 61013) from Karuh River ; one juvenile (KUHE 61015) from Panitiranggang , and one juvenile (MZB Amph 33630) from Jumantir . Three juveniles (MZB Amph 33517–19) were collected with holotype GoogleMaps .

Etymology. The species epithet refers to the name of the proposed new capital of Indonesia, located in Kalimantan (Borneo Part Indonesia), from where the new species is described. This name is an invariable noun in apposition.

Local common name. In Loksado village, the local people of Dayak Meratus ethnic call this frog “Lampinik”.

Suggested English common name. Nusantara Creek Frog.

Suggested Indonesian common name. Bangkong-tuli Nusantara.

Diagnosis. The new species clustered within the L. kuhlii complex in molecular analyses and can be distinguished from its congeners by the following combination of morphological characters: medium size (SVL 52.3–70.6 mm in males, 51.6–61.3 mm in females); toes fully webbed; tympanum hidden; dorsal skin of body weakly rugose; dorsal skin of tibia densely covered by small warts and scattered with low large warts; flap of skin on outer side of third finger well-developed, moveable; inner and outer webbing of fourth toe fairly well excised; disk of third finger not much wider than basal phalanx; disk of fourth toe wider than basal phalanx; nuptial pad on first finger without minute asperities in males; head longer than wide; and throat covered with small irregular dark gray blotches.

Description of the holotype (measurements in mm). Adult male (SVL 64.7), habitus stocky; head longer (HL 28.9, 44.6 % SVL) than wide (HW 27.3, 42.2 % SVL); rostrum longer (RL 9.9, 15.3 % SVL) than eye (ED 5.7, 8.7 % SVL); nostril dorsolateral on canthus, closer to snout tip (SL 4.4, 6.8 % SVL) than to eye (N-EL 5.5, 8.5 % SVL); internarial distance (IND 5.3, 8.1 % SVL) slightly shorter than interorbital distance (IOD 5.4, 8.3 % SVL); snout obtusely pointed in lateral view; canthus rounded; lore concave; pineal spot distinct; tympanum indistinct; pair of odontoid processes on lower jaw, obtuse in profile; vomerine teeth in oblique groups, groups separated from each another and from choana by half length of one group; vocal sac and vocal slits absent.

Forelimb stout, relatively short (FLL 31.6, 48.8 % SVL); fingers moderately slender; finger length formula II <I <IV <III; finger webbing absent; finger tips blunt, rounded, without circummarginal grooves; disk of third finger (3TDW 1.1, 1.7 % SVL) not wider than basal phalanx; inner palmar tubercle oval and low (IPTL 4.6, 7.1 % SVL); middle palmar tubercle oval and low, contacting outer palmar tubercle; outer palmar tubercle slightly oval and elongated; proximal subarticular tubercle slightly rounded, elevated; distal subarticular tubercle indistinct; skin flaps present on inner and outer side of second and third fingers, more developed on outer side of third finger than inner, freely moveable; supernumerary metacarpal tubercles absent; medial skin of first finger from base to level of subarticular tubercle yellowish, thickened, forming nuptial pad without minute asperities.

Hindlimb stout, relatively short (HLL 93.1, 143.9 % SVL), about three times length of forelimb, toe length formula I <II <V <III <IV; foot (FL 29.5, 45.6 % SVL) slightly longer than tibia (TL 29.3, 45.3 % SVL); tibiotarsal articulation reaching between eye and nostril in preserved condition; toes tips blunt, rounded; disk of fourth toe (4TDW 1.6, 2.4 % SVL) wider than basal phalanx; toes fully webbed, webbing formula I 1–1 II 1–1 III 1–1 IV 1–1 V; inner and outer webbing of fourth toe fairly well excised; skin flap on outer side of fifth and inner side of first toe present, moveable; proximal subarticular tubercle distinct, oval; middle subarticular tubercle distinct, oval slightly elongated, longer than proximal subarticular tubercle; distal subarticular tubercle distinct, oval; inner metatarsal tubercle elongated (IMTL 4.7, 7.2 % SVL); outer metatarsal tubercle absent.

Dorsal skin of head and anterior part of the trunk weakly rugose, wrinkled, without warts; posteriorly rugose with small warts; few small warts and wrinkles on upper eyelids; transverse strip between posterior margins of eyes; dorsolateral fold absent; short dorsolateral ridge behind eyes; strong, curved, supratympanic fold from eye to above arm base; ventral surface of abdomen and thigh smooth; cloaca rugose with small warts; ulnar side of hand with scattered translucent spinules; dorsal skin of tibia covered with numerous small warts and scattered with low large warts, each wart tipped with translucent spinule; tarsus covered with small warts dorsolaterally; skin flap along outer side of fifth toe with translucent spinules; ventral metatarsal skin of fourth toe with irregular translucent spinules.

Coloration. Dorsal side yellowish-brown with irregularly shaped, confluent dark spots; head with one dark brown interorbital bar; upper and lower lips with three dark brown bands; canthus and supratympanic fold covered by dark gray band; throat white, with small irregular dark gray blotches; abdomen yellowish-white; limbs marked dorsally with dark brown crossbars; thigh ventral side nearly translucent with thin yellowish blotches. In preservative, whole-body coloration turned blackish-red, dark gray spots on throat faded and become cream, and translucent spinules turned whitish.

Variation. Individuals of the type series were generally similar in proportions. Table 2 View TABLE 2 shows the individual variations in morphometric values. Males were greater than females in ROH and ROSL; while females were larger than males in ROW (Table 4). One male (MZB Amph 33527) had a larger body (SVL 70.5 mm vs. 64.7 mm) and a thicker nuptial pad than the holotype. One male (MZB Amph 33536) and one female (MZB Amph 33526) had a wide longitudinal white line from the snout to cloaca. One female (MZB Amph 15256) had irregular dark blotches covering the abdomen.

Comparisons. Limnonectes nusantara sp. nov. differs from Limnonectes maanyanorum sp. nov. by larger mean of female body size, SVL 51.6–61.3 mm, mean 49.2 ± SD 7 (vs. 40.4–58.5 mm, mean 49.2 ± SD 7.1); throat covered with small dark blotches, Fig. 7C, F View FIGURE 7 (vs. covered with confluent dark blotches, Fig. 5C, F View FIGURE 5 ); male dorsal surface of tibia covered with low warts and relatively larger, Figs. 7A, D View FIGURE 7 , 9C, D View FIGURE 9 (vs. well-elevated warts and relatively smaller, Figs. 5A, D View FIGURE 5 , 9A, B View FIGURE 9 ); and females having shorter head, RHL 40.0–43.1 % SVL, 41.8 ± SD 1.0 (vs. longer, 41.3–46.3 % SVL, mean 43.5 ± SD 1.7), shorter nostril-eye length, RN-EL 8.0–9.5 % SVL, mean 8.7 ± SD 0.5 (vs. longer, 9.1–10.6 % SVL, mean 9.8 ± SD 0.6), shorter snout length, RSL 6.0–7.2 % SVL, mean 6.6 ± SD 0.4 (vs. longer, 6.4–8.2 % SVL, mean 7.2 ± SD 0.6), shorter rostrum, RRL 14.1–16.8 % SVL, mean 15.5 ± SD 1.0 (vs. longer, 15.7–18.6 % SVL, mean 17.0 ± SD 0.9), and shorter forelimb RFLL 45.9–55.2 % SVL, mean 50.4 ± SD 2.8 (vs. longer, vs. 49.2–57.8 % SVL, mean 54.0 ± SD 2.8).

Limnonectes nusantara sp. nov. differs from L. barioensis and L. tawauensis by outer and inner webbing of fourth toes fairly well excised, Fig. 9F View FIGURE 9 [vs. little excised, Fig. 9G, H View FIGURE 9 ], first finger distinctly longer than second finger [vs. slightly longer: Matsui et al. (2024)], skin flap on outer side of third finger freely moveable [vs. weakly moveable, except L. tawauensis : Matsui et al. (2024)], male having obtuse odontoid processes tip (vs. sharply pointed, except L. barioensis : Matsui et al. 2024); and by female having longer first finger, RFFL 16.6–20.0 % SVL (vs. shorter, ≤ 15.6 % SVL: Matsui et al. 2024), and longer first toe, R1TOEL 20.2–21.7 % SVL (vs. shorter, ≤ 16.0 % SVL: Matsui et al. 2024).

Limnonectes nusantara sp. nov. differs from L. conspicillatus , L. lambirensis , L. mocquardi , L. penerisensis , L. paginatanensis , L. separatus , L. lanjakensis , L. abanghamidi , L. batulawensis , and L. paulyambuni by dorsal tibia having pattern I of warts (vs. pattern II or III, see Table 3 View TABLE 3 ). Additionally, Limnonectes nusantara sp. nov. differs from L. mocquardi , L. paginatanensis , L. separatus , L. separatus , L. abanghamidi , L. batulawensis , and L. paulyambuni , by having first finger distinctly longer than second finger [vs. first finger as long as or slightly shorter than second: Matsui et al. (2024)]. Limnonectes nusantara sp. nov. differs from L. lambirensis , L. mocquardi , L. paginatanensis , and L. abanghamidi by outer side of third finger having moveable skin flap [vs. weekly moveable or non-moveable: Matsui et al. (2024)].

Limnonectes nusantara sp. nov. differs from L. asperatus , L. rhacodus , L. deinodon , L. hikidai , L. cintalubang , L. sinuatodorsalis , and L. kong , by having fully webbed toes [vs. fourth toe not webbed to base of tip: Inger et al. (1996), Dehling (2014), Matsui & Nishikawa (2014), Matsui et al. (2014b), Matsui (2015), Dehling & Dehling (2017)]; and odontoid processes tip obtuse in males [vs. pointed, except L. kong : Inger et al. (1996), Dehling (2014), Matsui & Nishikawa (2014), Matsui et al. (2014b), Matsui (2015), Dehling & Dehling (2017)]. Additionally, Limnonectes nusantara sp. nov. differs from L. kong by absence of minute asperities on male nuptial pads [vs. present: Dehling & Dehling (2017)], and moveable skin flap on the outer side of third finger [vs. non-moveable: Dehling & Dehling (2017)].

Limnonectes nusantara sp. nov. differs from L. kuhlii by the absence of thickened skin on the ventral surface of the anterior chin in male (vs. present), and nuptial pad present in males (vs. absent). Limnonectes nusantara sp. nov. differs from L. sisikdagu by absence of translucent spinules on ventral surface of anterior chin of males [vs. present: McLeod et al. (2011)], and absence of minute asperities on male nuptial pads [vs. present: McLeod et al. (2011)].

Limnonectes nusantara sp. nov. differs from L. utara and L. selatan by smaller mean of female body size, 51.6–61.3 mm, mean 55.9 SD ± 3.0 [vs. 59.2–78.7 mm, mean 69.5 ± SD 6.8 in L. utara ; 61.6–73.0 mm, mean 70.0 SD ± 3.8 in L. selatan : Matsui et al. (2014a)]; having few large warts on tibia [vs. many large warts: Matsui et al. (2014a)], and absence of minute asperities on males nuptial pads [vs. present: Matsui et al. (2014a)]. Additionally, Limnonectes nusantara sp. nov. differs from L. utara by smaller of male body size, 52.3–70.6 mm [vs. 70.0– 79.1 mm: Matsui et al. 2014a], and less confluent dark markings on dorsum [vs. more confluent: Matsui et al. (2014a)].

Distribution and natural history. Limnonectes nusantara sp. nov. is distributed at an altitude of 177–1000 m a.s.l. in the central part of the Meratus Mountain Range. The type specimens were found along a rocky tributary up to 2 m from the water ( Fig. 10B View FIGURE 10 ). The holotype was collected on the ground at the edge of the river around 19:45 h. Other specimens have been found on leaves and rocks, and the species is rarely seen in water. The species inhabits primary and secondary forests as well as nearby disturbed areas. The following anuran species have been found at the type locality were Ansonia spinulifer (Mocquard) ; Chaperina fusca Mocquard ; Hylarana picturata ; Ingerophrynus divergens (Peters) ; Kalophrynus meizon ; L. leporinus ; L. paramacrodon ; Leptobrachium abbotti ; Limnonectes sp. 2 ; Microhyla sundaica Trofimets, Dufresnes, Pawangkhanant, Bragin, Gorin, Hasan, Lalremsanga, Muin, Le, Nguyen, Suwannapoom & Poyarkov ; Microhyla malang Matsui ; Pelobatrachus kalimantanensis ; Leptobrachella fritinniens ; Phrynoidis asper ; and Staurois guttatus .