Bioacoustics of Minervarya manoharani

A male (ZSI/WGRC/V/A/950, from Chathankod-Bonnacaud) of Fejervarya manoharani sp. nov. produced a single type of call with a pulsatile temporal structure (Figs. 8E–G). Calls were not delivered in groups and had uniform intervals. A typical advertisement call (Fig. 8F) had a duration of 260.1 ms with 76 pulses delivered at rate of 301.5 pulses per second. Call had a rise time of 127.2 ms and a short fall time of 11.7 ms. The spectrum was characterized by two broad peaks with the overall dominant frequency of 2.6 KHz (Fig. 8H). The animal was recorded on 24 June 2015, between 19:00–21:00 hours. Air temperature at the time of recording: dry bulb 25◦C, wet bulb 24◦C. In comparison to Fejervarya rufescens, the call of F. manoharani had a higher number of pulses, 76 pulses (vs. 52 pulses in F. rufescens) and was delivered at a faster rate, 301.5 pulses per second (vs. 227.1 pulses per second in F. rufescens). The overall dominant frequency of F. rufescens call (2.9 KHz) was higher compared to F. manoharani (2.6 KHz). The call rise time was also higher in F. rufescens, 221.9 ms (vs. 127.2 ms in F. manoharani), making the calls of both these species considerably distinct from each other (Figs. 8B, 8F).

Distribution and natural history. Fejervarya manoharani sp. nov. is currently known only from its type locality Chathankod–Bonnacad, and Kattalapara (Shendurney WLS) in Agasthyamala hills, south of both the Palghat gap and Shencottah gap in the Western Ghats state of Kerala ( Fig. 3 ). During the monsoon period (June– July), aggregations of a large number of calling males were observed around temporary water collections on open rocky areas surrounded with secondary forest. Though breeding activity was not observed at that time, we collected tadpoles of this species (genetically confirmed) from water puddles on the vegetated edges of large rocky areas, suggesting that this species probably breeds early, either immediately after the summer showers or during the initial monsoon period (May–June). Like other species in the Fejervarya rufescens group, animals are usually sensitive and with any slight movement around them they immediately stop calling, jump away and try to hide inside nearby muddy areas.

Fejervarya manoharani differs from F. kadar by its dorsal skin with more prominent glandular warts (vs. scattered glandular warts); snout vertical in lateral view (vs. obtuse); relatively smaller snout-vent size, male SVL 28.1–30.0 mm, N = 4 (vs. larger, male SVL 31.0– 33.5 mm , N = 3); eye length relatively longer than head length, male EL 3.9–4.1 mm , HL 10.4–11.0 mm, EL/HL ratio 36.7 – 37.5%, N = 4 (vs. shorter, male EL 4.0– 4.2 mm , HL 11.7–12.1 mm , EL/HL ratio 33.6–34.7%, N = 3); forearm length relatively shorter than hand length, male FAL 5.1–5.4 mm , HAL 6.4–6.9 mm , FAL/HAL ratio 76.8–79.7%, N = 4 (vs. longer, male FAL 5.7–6.2 mm , HAL 6.6–7.1 mm , FAL/HAL ratio 85.3–87.3%, N = 3); and relatively more webbing between toes, male I2– 2II 2– –3– III2–3 1/ 3IV 3 1/3– 2V , specifically the fourth toe webbing extending close to the second subarticular tubercle on either side (vs. less, male I2 – –2– II2 – –3– III2–3 2/ 3IV 3 2/3– 2V , specifically the fourth toe webbing extending slightly above the third subarticular tubercle on either side). For differences with Fejervarya neilcoxi see ‘morphological comparison’ of that species. Description of holotype (measurements in mm) . Adult male (SVL 30.0), rather stout; head wider than long (HW 11.7, HL 11.0); snout rounded in dorsal view and vertical in lateral view, its length (SL 4.4) longer than horizontal diameter of eye (EL 4.1); loreal region acute with rounded canthus rostralis; interorbital space flat (IUE 2.0), narrower than upper eyelid width (UEW 3.0) and internarial distance (IN 2.6); nostril nearly as close to tip of snout (NS 1.9) and to eye (EN 2.0); tympanum (TYD 1.5) 36.6% of eye diameter (EL 4.1); tympanum-eye distance (TYE 1.4) subequal to the tympanum diameter (TYD 1.5); supratympanic fold well developed, extends from posterior corner of eye to near the shoulder; vomerine ridge present, bearing small teeth, at an angle of 45° to the body axis, as close to choanae as to each other; tongue moderately large, emarginated, bearing no median lingual process; rictal gland present at labial commissure of the mouth. Arms short, forearm length (FAL 5.4) shorter than hand length (HAL 6.8); relative length of fingers IV<II<I<III (FL I 3.2, FL II 2.5, FL III 3.8, FL IV 2.0); finger tips rounded, slightly enlarged without discs, fingers without fringes, webbing between fingers absent; subarticular tubercles prominent, circular; one distinct palmar tubercle, oval, bifid; supernumerary tubercles absent. Hind limbs short, thigh (TL 13.5) shorter than shank (SHL 13.8) and foot (FOL 14.9), distance from the base of tarsus to the tip of toe IV (TFOL 21.2); toes long, relative length of toes I<II<V<III<IV; toe tips rounded, slightly enlarged without discs, toes without fringes, webbing between toes small: I2– 2II 2– –3– III2–3 1/ 3IV 3 1/3– 2V ; inner toe length (ITL 2.3); subarticular tubercles prominent, all present, circular; inner metatarsal tubercle prominent, shovel-shaped (IMT 1.8); outer metatarsal tubercle small (OMT 0.4), rounded; supernumerary tubercles absent. Skin of snout shagreened with prominent granular projections and interrupted linear warts, upper eyelids prominently tuberculate, anterior and posterior parts of back, and upper and lower parts of flank shagreened with prominent granular projections and scattered glandular warts; interrupted inverse V-shaped ridge on center of dorsum; dorsal surfaces of forelimb, thigh and shank shagreened with scattered granular projections. Ventral surface of throat, chest, belly and limbs smooth to shagreened, anterior part of thigh sparsely granular; fejervaryan line present on both sides of the belly ( Fig. 11 ). Colour of holotype . In life. Dorsum, upper eyelids and lateral side of snout yellowish-brown with prominent greyish-brown blotches and a few brick red spots, upper and lower lip with faint alternate greyish-brown and white cross bands; tympanum dark greyish-brown; anterior parts of flank light greyish-brown with scattered white mottling; forelimbs and hind limbs light yellowish-brown with greyish-brown transverse bands and scattered brick red spots; groin yellowish-brown; webbing light greyish-brown; anterior part of thigh light yellowish-brown with greyish-brown reticulations. Ventral surface of throat light flesh red with two lateral black calling patches; belly white; forearm and foreleg light flesh red with dark brown mottling on the margins ( Fig. 11 A). In preservation . Dorsum dark greyish-brown with blackish-brown markings, forelimbs and hind limbs light brown with dark brown transverse bands, posterior parts of thigh light brown with faint dark brown reticulations. Ventral surface of throat light grey with two lateral black calling patches on either side; belly off-white and margins of the limbs grey with dark grey mottling ( Fig. 11 ). Variations. Morphometric data from four adult males and two adult females, including the holotype, is given in Table 7 . Colour in preservation . ZSI/WGRC/V/A/947 and ZSI/WGRC/V/A/949: dorsum light-greyish brown with dark brown markings; ZSI/WGRC/V/A/950: dorsum light-greyish brown with more prominent dark blackishbrown markings. Secondary sexual characters. Male : calling patches on either side of the throat. Female (ZSI/WGRC/V/A/ 948): pigmented eggs present (diameter 1.9 ± 0.3 mm , N = 15). Vocalization. A male (ZSI/WGRC/V/A/950, from Chathankod-Bonnacaud) of Fejervarya manoharani sp. nov. produced a single type of call with a pulsatile temporal structure ( Figs. 8 E–G). Calls were not delivered in groups and had uniform intervals. A typical advertisement call ( Fig. 8 F) had a duration of 260.1 ms with 76 pulses delivered at rate of 301.5 pulses per second. Call had a rise time of 127.2 ms and a short fall time of 11.7 ms. The spectrum was characterized by two broad peaks with the overall dominant frequency of 2.6 KHz ( Fig. 8 H). The animal was recorded on 24 June 2015 , between 19:00–21:00 hours. Air temperature at the time of recording: dry bulb 25◦C, wet bulb 24◦C. In comparison to Fejervarya rufescens , the call of F. manoharani had a higher number of pulses, 76 pulses (vs. 52 pulses in F. rufescens ) and was delivered at a faster rate, 301.5 pulses per second (vs. 227.1 pulses per second in F. rufescens ). The overall dominant frequency of F. rufescens call (2.9 KHz) was higher compared to F. manoharani (2.6 KHz). The call rise time was also higher in F. rufescens , 221.9 ms (vs. 127.2 ms in F. manoharani ), making the calls of both these species considerably distinct from each other ( Figs. 8 B, 8F).