Indotyphlus maharashtraensis, Giri, Varad, Gower, David J. & Wilkinson, Mark, 2004

Giri, Varad, Gower, David J. & Wilkinson, Mark, 2004, A new species of Indotyphlus Taylor (Amphibia: Gymnophiona: Caeciliidae) from the Western Ghats, India, Zootaxa 739, pp. 1-19 : 2-9

Indotyphlus maharashtraensis sp. nov.

( Figs. 1–3 , Table 1)

Holotype: Bombay Natural History Society, Mumbai, India ( BNHS) 4217. A female, collected near Dhanagarwada, Humbarli village, near Koyna, Satara District, Maharashtra, India, by Varad Giri, Sameer Kehimkar, Ishan Agarwal and Vithoba Hegade, 19th June 2003. The specimen was found on a plateau ( Fig. 4 ), under a rock in an open patch of grass surrounded by semievergreen forest. The locality is situated in the Western Ghats at approximately 1042 m above sea level.

Specimen number ( BNHS prefix) 4217* 4200 4218 4219 4220 4221

Sex f f m f m? f

Total length 181 197 78 138 72 100

Number of primary annuli 127 133 129 131 126 129

Anteriormost primary annulus with indication of secondary groove 70 77 70 88 68 69

Anteriormost primary bearing dorsally complete secondary groove 87 96 79 101 74 78

Anteriormost primary bearing ventrally complete secondary groove 111 114 c.114 118 113 112

Head length (snout tip to first nuchal groove, laterally) 5.3 5.5 3.3 4.7 3.6 4.0

Distance between snout tip and angle of jaws 4.1 4.5 3.0 3.4 2.8 3.4

Distance between tip of lower jaw and first nuchal groove (laterally) 4.7 4.9 3.0 4.0 3.4 3.4

Distance between tip of lower jaw and angle of jaws 3.7 3.3 2.7 3.1 2.7 2.7

Length of first nuchal collar (measured laterally) 1.5 1.7 0.9 1.5 0.9 1.0

Length of second nuchal collar (measured laterally) 2.1 2.1 1.3 1.8 1.2 1.5

Head width at first nuchal groove 3.6 3.7 2.2 2.7 2.1 2.3

Head width at angle of jaws 3.3 3.5 2.0 2.5 2.0 2.2

Distance between external nares 1.2 1.2 0.8 1.3 0.9 0.9

Distance between tentacles 2.3 2.1 1.3 2.0 1.5 1.6

Distance between eyes (where visible) 2.2 na 1.3 1.8 1.4 1.5

Distance between external naris and tentacle 1.4 1.3 0.9 1.2 0.9 0.9

Distance between external naris and eye 1.9 na 1.1 1.6 1.3 1.3

Distance between tentacle and eye 0.5 na 0.3 0.5 0.3 0.4

Distance between tentacle and margin of upper lip 0.6 0.8 0.5 0.6 0.4 0.5

Distance between external naris and first nuchal collar groove 4.7 5.0 3.0 4.0 3.2 3.4

Distance between external naris and angle of jaws 3.4 3.3 2.1 2.8 2.4 2.7

Distance between tentacle and tip of snout 2.0 1.8 1.3 1.9 1.3 1.5

Distance between tentacle and angle of jaws 2.1 2.2 1.3 1.8 1.7 1.6

Distance between eye and angle of jaws 1.5 na 1.0 1.2 1.0 1.2

Distance between snout tip and anterior margin of mouth 0.8 1.1 0.7 0.7 0.5 0.7

Width at midbody 3.8 3.6 1.7 2.8 1.5 2.5

Body width at level of vent 2.7 2.4 1.4 2.0 1.1 1.7

Distance from vent to body terminus 1.7 1.5 1.0 1.4 0.8 1.0

Circumference at midbody 14 14 6 10 8 8

Premaxillary­maxillary teeth 25 24 19 22 22 20

Vomeropalatine teeth 24 26 20 23 22 22

Dentary teeth 20 21 19 22 19 21

Splenial teeth 4 3 4 4 3 3

......continued on the next page Specimen number ( BNHS prefix) 4222 4223 4224 4225 4333 4334

Sex f? m m f f f

Total length 70 179 205 123 145 193

Number of primary annuli 129 124 125 131 128 133

Anteriormost primary annulus with indication of secondary groove 68 58 72 81 66 64

Anteriormost primary bearing dorsally complete secondary groove 76 71 85 100 83 91

Anteriormost primary bearing ventrally complete secondary groove 108 100 107 113 107 118

Head length (snout tip to first nuchal groove, laterally) 3.6 6.0 7.0 4.4 4.4 5.5

Distance between snout tip and angle of jaws 2.9 4.4 5.4 3.6 3.4 4.4

Distance between tip of lower jaw and first nuchal groove (laterally) 3.3 5.2 6.0 3.9 4.0 4.8

Distance between tip of lower jaw and angle of jaws 2.3 3.5 4.6 3.2 2.8 3.9

Length of first nuchal collar (measured laterally) 1.0 1.5 1.9 1.4 1.4 1.5

Length of second nuchal collar (measured laterally) 1.3 2.0 2.3 1.7 1.7 2.0

Head width at first nuchal groove 2.0 3.1 3.8 2.7 3.1 3.6

Head width at angle of jaws 2.0 3.0 3.7 2.5 2.5 3.1

Distance between external nares 0.9 1.2 1.4 1.1 1.0 1.4

Distance between tentacles 1.4 2.3 2.6 1.9 1.9 2.4

Distance between eyes (where visible) 1.3 2.2 2.5 1.8 1.6 2.4

Distance between external naris and tentacle 0.9 1.5 1.9 1.0 1.0 1.6

Distance between external naris and eye 1.2 2.1 2.4 1.5 1.6 2.5

Distance between tentacle and eye 0.3 0.5 0.6 0.5 0.5 0.7

Distance between tentacle and margin of upper lip 0.4 0.6 0.8 0.6 0.5 0.8

Distance between external naris and first nuchal collar groove 3.9 5.2 6.5 3.9 4.0 4.9

Distance between external naris and angle of jaws 2.4 3.9 4.5 3.1 2.9 3.9

Distance between tentacle and tip of snout 1.4 2.2 2.4 1.7 1.5 2.1

Distance between tentacle and angle of jaws 1.4 2.5 2.4 2.0 1.9 2.4

Distance between eye and angle of jaws 1.2 1.7 1.9 1.7 1.2 2.0

Distance between snout tip and anterior margin of mouth 0.6 0.8 1.1 0.8 0.5 0.9

Width at midbody 2.2 3.6 4.6 2.7 4.0 5.0

Body width at level of vent 1.1 3.2 3.9 2.0 2.6 3.2

Distance from vent to body terminus 0.8 2.0 2.3 1.3 1.5 2.0

Circumference at midbody 6 13 15 9 13 16

Premaxillary­maxillary teeth 20 22 25 22 22 26

Vomeropalatine teeth 23 24 28† 24 23 24†

Dentary teeth 20 19 21 21 19 20

Splenial teeth 4 4 2 4 4 4 Paratopotypes: Eleven further specimens collected either on the same day (or within two days) as the holotype ( BNHS 4200, 4218 to 4225) or on 20th August 2004 ( BNHS 4333, 4334), all from the same locality and habitat as the holotype.

Diagnosis: An Indotyphlus differing from I. battersbyi in having secondary annular grooves present anterior to the 100th primary annulus behind the nuchal collars, and in having a depressed preanal strip (longer in adult males) anterior to the disc surrounding the vent.

Description of the holotype: Some morphometric and meristic data are given in Table 1. The holotype is in good condition generally. It is a little dehydrated so that the skin throughout much of the body is roughened by raised glands, especially on the dorsum. Dehydration has also caused a darkening in colour, and is probably responsible for an intermittent midventral groove that is not present in life. There is a small (7 mm) midventral longitudinal incision into the body cavity 65 mm in front of the vent. There is a small V­shaped scar on the posterior part of the dorsal surface of the head.

The natural body shape is subcylindrical, slightly dorsoventrally compressed throughout most of the body (a little more so in preservative), distinctly flattened on the ventral surface for approximately the terminal 20 mm. It is fairly uniform in width, but gently narrowing in the anterior fifth (where it is less dorsoventrally compressed). The body also narrows gradually for its posterior third, narrowing strongly in lateral view from just anterior to the level of the vent.

In dorsal view, the head tapers strongly from the level of the occiput to the external nares, with a slight bulging in the region of the tentacles. Anterior to the nares, it terminates in a rounded, narrow snout tip. In lateral view, the top of the head is straight, with no strong bulges. The margin of the upper lip is not markedly concave in lateral view. The snout tip is bluntly rounded, and its apex lies just below the horizontal level of the naris. The distance between the jaw angle (the corner of the mouth) and the top of the head is marginally (less than one and a half times) greater than the distance between the jaw angle and the lower surface of the lower jaw.

The eyes are visible (more clearly visible in life) through the skin as small dark spots (no lens visible) at the posterior end of a whitish (pale pink in life) stripe extending from immediately posterior to the eye to immediately anterior to the tentacle. In lateral view, the eye lies approximately halfway between the margin of the upper lip and the top of the head. In dorsal view, the eyes are inset from the lateral margins of the head. The eye region is not elevated or depressed.

In life, the tentacles are short and globular (i.e. non­filamentous) but with a pointed tip. The tentacular apertures are horseshoe shaped (posteriorly concave) when occluded by a distinct flap that is continuous posteriorly with the skin. They are raised and dorsolaterally positioned, clearly visible in dorsal view, visible only as a bulge in ventral view. In lateral view, each tentacle appears approximately twice as close to the top of the head as to the margin of the upper lip (0.6 mm), and just above an imaginary straight line between eye and naris. In lateral view, an imaginary straight line extending backwards from the naris through the position of the tentacular aperture crosses the upper margin of the head at about the second nuchal groove. The tentacular apertures are far posterior to the anteriormost margin of the mouth, 2 mm from the tip of the snout. The distance between tentacle and eye (0.5 mm) is substantially smaller than between tentacle and naris (1.4 mm).

The very small (0.2 mm) subcircular nares are set back slightly from the tip of the snout. They are not notably closer to the anteriormost margin of the mouth than to the level of the snout tip or vice versa. They are 1.2 mm apart, visible dorsally, anteriorly and laterally, but not ventrally. Each naris lies in the anteromedial part of a 0.7 mm wide whitish spot. The tip of the snout lies 0.8 mm in front of the anteriormost margin of the upper lip. The underside of the rostrum is essentially flat. In ventral view, the tip of the lower jaw is broadly rounded, more so than the tip of the snout.

The jaw angles are not cut and tooth counts are approximate. We counted 25 premaxillary­maxillary, 24 vomeropalatine, 20 dentary, and 4 splenial teeth (including empty ‘sockets’). The tooth crowns of all series are gently recurved and, as far as can be ascertained, all are bicusped with smaller labial cusps. The dentary teeth are the largest, followed by those of the premaxillary­maxillary (PMM) series. The teeth of the splenial, and vomeropalatine (VP) series are the smallest. The PMM, VP and splenial teeth show little variation in size within each series. The largest teeth in the dentary series are in the third position behind the anterior tip (symphysis) of the mandible, where they are twice the size of the largest in the PMM series. Behind this, the dentary teeth gradually decrease in size, being very small posteriorly. The VP series lacks diastemata, and is masked in lateral view by the outer, PMM series. The splenial teeth are less than one third the size of the largest dentaries.

The subcircular choanae are large and separated by a distance that is approximately equal to the width of each choana. Choanal valves are not clearly visible. The fleshy tip of the tongue is unattached anteriorly and does not overlie the splenial teeth. Laterally it is separated from the gingivae by a deep groove. There is a pair of large, prominent narial plugs. Their anterior and medial margins are clearly demarcated by a groove, but posteriorly they are smoothly continuous with the surface of the rest of the tongue. The tongue lacks a midline longitudinal groove. Posterior to the narial plugs, and separated from the plugs by a gap, are a pair of grooves close, and parallel, to the lateral edges of the tongue. There are some longitudinal plicae between these grooves and the posteromedial edge of the plugs. The tongue tip is pink, the narial plugs are dark, and the region between them whitish.

The nuchal region is slightly broader than the adjacent areas. The two nuchal collars are marked clearly by three nuchal grooves that have the same whitish colour (laterally and ventrally) as the following annular grooves. The second collar (2.1 mm, measured laterally) is longer than the first (1.5 mm). The first (anteriormost) nuchal groove is narrowly incomplete ventrally and more broadly incomplete middorsally. It curves forwards slightly midventrally. The second nuchal groove (between the first and second collars) is incomplete only middorsally. It is marked ventrally by a slight fold and is notably paler than the adjacent area. The third nuchal groove, marking the end of the nuchal collar region, is broadly incomplete midventrally and narrowly incomplete middorsally. The first collar bears a faint, short middorsal transverse groove. The second collar bears a faintly indicated, broad, middorsal transverse groove, more pronounced on the left and seemingly incomplete across the midline. A fainter, more superficial crease lies between this transverse groove and the back of the second collar. Neither collar bears transverse grooves ventrally or laterally. A midventral longitudinal groove extends from about halfway between the tip of the lower jaw and the first nuchal groove to the second nuchal groove.

The nuchal and annular grooves are mostly perpendicular to the long axis of the body. The annuli are marked by whitish coloured (more pronounced laterally) grooves that are increasingly conspicuous posteriorly. There are 127 primary annuli. The annular grooves are mostly incomplete dorsally for the first two thirds or so of the body, and this incompleteness decreases posteriorly. Ventrally, they are mostly complete but faintly indicated. The first, second and third primary annuli bear short, faint, dorsolateral transverse grooves, clear only on the left side. These are in a position that might be expected of secondary annular grooves, but the first clear indication of a secondary annular groove behind this (which we consider the first secondary), is dorsolaterally on the left of the 70th primary annulus. The next five primaries (71–75) also bear dorsolateral secondary grooves on the left side only, but secondary grooves are on both sides of the body behind this. The anteriormost secondary annular groove that extends across the dorsal midline is on the 87th primary annulus, and all primary and secondary grooves posterior to this also cross the dorsum. Secondary annular grooves extend across the midline of the ventral surface from the 111th primary annulus backwards. However, the annular groove is interrupted midventrally by the vent and surrounding disc. There are no annular grooves posterior to the vent, and there is a short terminal cap.

Searches for annular scales were made at three points along the body. At the posterior groove of the 10th primary annulus anterior to the posterior terminus, there are four scale rows dorsally. Two rounded but subquadrangular scales removed from here measured 0.6 x 0.9 mm and 0.5 x 0.6 mm. The fold or pocket holding these scales is about as deep as the length of each primary annulus in this region. Ventrally at this point, one or two scale rows lie in a fold that is less than one secondary annulus deep. At about the 75th primary annulus (just behind where secondary grooves begin), the fold in the dorsal part of the annular groove is not well developed. It contains a single row of subcircular scales, one of which measured 0.3 x 0.2 mm. There are no scales ventrally at this position. At the 50th primary annulus, there are no pockets or scales.

The body terminus is bluntly rounded in dorsal view. In lateral view, the ventral surface appears flat, the short terminal cap tapers more steeply from the dorsum, and is upturned only slightly on its ventral surface. There is no indication of a terminal keel. The subcircular vent lies just 1.7 mm from the body terminus within a small subcircular disc. The vent is slightly irregular, but the disc has a pattern of five posterior and four anterior denticles, the posteromedial of which is the largest. No papillae are evident on any of the denticulations. The subterminal area around the disc and onto the terminal cap is flattened. There is a long (c. 6 mm), progressively narrowing and slightly depressed, mid­ventral preanal strip ( Fig. 1 D) in which granular glands are conspicuously absent so that superficially annular grooves appear (but are not) incomplete.

In preservative and in life the ground colour of the dorsal surface of the body is mostly brownish, but more grey/lavender posteriorly, and paler laterally and ventrally. Granular glands are visible as white flecks scattered over much of the body. Alignment of granular glands along annular grooves makes the grooves conspicuous laterally throughout. The extent to which annuli are marked by glands, both dorsally and ventrally, increases gradually towards the posterior of the body as the annular grooves become more complete. Granular glands are much less abundant or absent on the head and the preanal strip.

There is a paler, triangular gular patch on the underside of the first collar and onto the lower surface of the head between the mandibular rami. Here the longitudinal groove is enveloped by this patch. The paler patch (not visible laterally) is separated from the whitish lower lips by a darker ground colour. In dorsal view, the head is darker and more laven­ der than the nuchal region (and body), except for pale, broad eye­tentacle stripes, halos surrounding the nares, and patches in the position of the slightly bulging depressor mandibulae muscles. The snout tip is also pale, but less so than the halos around the nares, from which it is incompletely separated. The lips are edged in a whitish colour, more broadly on the lower jaw, particularly anteriorly. In dorsal and lateral views, the eye­tentacle stripes are subparallel to the longitudinal axis of the head. In dorsal view, these stripes reach the margins of the head. In life, the paler regions of the head are infused with blood and pinkish. Dorsally, the terminal cap is a darker lavender than the preceding annuli. It has a whitish tip that is continuous with pale patches extending lateral and anterior to the disc. The preanal strip is lavender grey and this extends back as a narrow area surrounding the white disc ( Fig. 1 D). Areas either side of this and back onto the underside of the terminal cap are white.

Etymology: The species is named for Maharashtra, the Indian State within which the type locality lies.

Figures

FIGURE 1. Figures (from camera lucida drawings) of the head and posterior terminus of Indotyphlus maharashtraensis. For the holotype (BNHS 4217, an adult female), the head and nuchal region are shown in A) dorsal, B) lateral, and C) ventral views, with paler regions at the snout tip, eye­tentacle stripe, margins of the lips, superficial to the depressor mandibulae muscles, and gular patch indicated by dotted lines. Ventral views of the posterior terminus are shown for D) the holotype, and E) a paratopotype (BNHS 4223, an adult male). In both specimens, the disc surrounding the vent and the tip of the terminus are whitish. The preanal strip extending anteriorly from immediately around the disc is an even lavender­grey colour, while the background colour of the rest of the underside of the posterior of the body is lavender­grey, flecked with large white glands. For dimensions of these two specimens, see Table 1.

FIGURE 2. Photographs of Indotyphlus maharashtraensis, showing whole adult (upper) and lateral view of head of same specimen (lower left) in life, and ventral view of terminus of paratopotype male BNHS 4223 in preservation (lower right).

FIGURE 4. Photographs of the habitat at the type locality for Indotyphlus maharashtraensis. This locality has strongly demarcated dry (left, seen in January 2003) and monsoon (right, September 2003) seasons.