Joseph's Racer

biology_ecology

Habitat and natural history. Platyceps josephi sp. nov. mostly inhabits open habitats with sandy or rocky patches in grasslands and scrublands in both inland and coastal areas of Tamil Nadu from elevations between 10 and 580 m a. s. l. (see Fig. 21 and Appendix 9). Most of the areas where they occur receive less than 500 mm annual rainfall except locations near the rain shadowed areas close to the Western Ghats receives higher rainfall (Anaikatti and Megamalai) (http: // www. tnsccc. in / rainfall. php). Sagadevan et al. (2019) report a sighting from the dry evergreen forest in Auroville, Villupuram district, but it is pertinent to mention here that this region was originally a scrub jungle and the current dry evergreen forest is an anthropogenic habitat created a few years ago (Blanchflower 2005). Platyceps josephi sp. nov. is usually observed under thorny bushes, rock boulders, paddy fields, heaps of dry coconut fronds and seen crossing roads (Rajendran 1986; NJ and MS personal observation). The holotype (NCBS-AU 732) and the paratype (BNHS 3156) were both collected from human habitations. ZSI-CZRC- 6639 was found under heaps of coconut fronds within a plantation surrounded by dr

Revealing two centuries of confusion: new insights on nomenclature and systematic position of Argyrogena fasciolata (Shaw, 1802) (auctt.), with description of a new species from India (Reptilia: Squamata: Colubridae)

description

Description of the holotype. Morphometric and merestic data are provided in Table 2. Female. Specimen in good condition with three incisions into coelom at 80 th, 106 th and 123 rd ventral respectively. Body subcylindrical, dorsoventrally flattened. Head ovate, barely wider than the anterior end of body. Total lenghth 934 mm; snout-vent length 758 mm; tail length 176 mm; ratio tail length / total length 0.19; head length 24.0 mm; rostral large, 2.2 times broader than high, not protruding, rounded in dorsal view, and wedged in between internasals; the latter smaller (1.5 mm) and distinctly shorter along median suture than prefrontals (2.5 mm); mid-line suture between internasals and pre-frontals in straight line; distance from posterior tip of rostal to anterior edge of frontal 4.2 mm, the latter bell-shaped, 6.4 mm long with a maximum width of 4.7 mm; interocular width 7.0 mm; parietals 6.3 mm long, outer lateral and posterior margins of parietals surrounded by 13 scales between the upper postoculars; nasal completely divided, in contact with first and anterior half of second supralabial; nostril large in anterior shield; distance between posterior margin of nostril and anterior bo

Revealing two centuries of confusion: new insights on nomenclature and systematic position of Argyrogena fasciolata (Shaw, 1802) (auctt.), with description of a new species from India (Reptilia: Squamata: Colubridae)

diagnosis

Diagnosis. A medium sized (maximum total length 951 mm) snake with countersunk lower jaw; dark brownish dorsum; head with irregular white spots, two slanting roughly " ∏ " shaped white markings with black edges on either side, starting on the back of the head (behind parietals) extending into the body, almost the length of head; 13 - 18 prominent white bands in the anterior region of the dorsum in both juveniles and adults; 34 - 48 total bands on the body in both juveniles and adults; 23: 21 (exceptionally 23): 16 - 18 smooth dorsal scale rows; 189 - 218 ventrals (males: 192 - 197; females: 189 - 216); 76 - 88 subcaudals (males: 83 - 88; females: 76 - 88); cloacal plate divided; tail without bands and underside creamish. Its dentition is characterized by 12 - 16 maxillary teeth, the last two enlarged and separated by a diastema, 9 - 11 palatine teeth, 14 - 15 pterygoid teeth and 15 - 16 mandibular teeth. Platyceps josephi sp. nov. shows most similarities with its sister taxon P. plinii in regard to pholidosis and colour pattern but can be distinguished from the latter by its lower number of midbody dorsal scale rows (21 vs. 23), its lower mean value of ventral scales (202 vs. 214),

Revealing two centuries of confusion: new insights on nomenclature and systematic position of Argyrogena fasciolata (Shaw, 1802) (auctt.), with description of a new species from India (Reptilia: Squamata: Colubridae)

discussion

Differences between Platyceps josephi sp. nov. and South Asian congeners. Platyceps josephi sp. nov. is distinguished clearly from P. bholanathi, P. mintonorum, P. noeli, P. rhodorachis, P. sindhensis and P. ventromaculatus by its higher number of midbody dorsal scale rows (21 vs. 19) and from P. gracilis by its lower mean value of ventral scales (202 vs. 214), its lower value of subcaudal scales without overlapping (88 maximum vs. 118 minimum), its different neck pattern (whitish ∏ - shaped marking vs. a yellowish-cream and black edged V-shaped marking), and by differing dorsal body pattern (irregular whitish transverse bars stippled with black vs. dorsal yellowish-cream and black-edged transverse bars). Platyceps josephi sp. nov. shows similarities with P. plinii with regard to pholidosis and colour pattern but can be distinguished from the latter by its lower number of midbody dorsal scale rows (21 vs. 23), its lower mean value of ventral scales (202 vs. 214), its lower mean value of subcaudal scales (82 vs. 87), and its lower mean of the sum of ventral and subcaudal scales (285 vs. 304). Comparision of Osteology. The first detailed description of osteological features of Platyc

Revealing two centuries of confusion: new insights on nomenclature and systematic position of Argyrogena fasciolata (Shaw, 1802) (auctt.), with description of a new species from India (Reptilia: Squamata: Colubridae)