Micrurus tikuna, Feitosa, Darlan Tavares, Jr, Nelson Jorge Da Silva, Pires, Matheus Godoy, Zaher, Hussam & Prudente, Ana Lúcia Da Costa, 2015

Feitosa, Darlan Tavares, Jr, Nelson Jorge Da Silva, Pires, Matheus Godoy, Zaher, Hussam & Prudente, Ana Lúcia Da Costa, 2015, A new species of monadal coral snake of the genus Micrurus (Serpentes, Elapidae) from western Amazon, Zootaxa 3974 (4), pp. 538-554 : 539-548

publication ID	https://doi.org/ 10.11646/zootaxa.3974.4.5
publication LSID	lsid:zoobank.org:pub:3D4D0400-6B17-4EDB-ABED-D3F88D4E5ABB
DOI	https://doi.org/10.5281/zenodo.5665652
persistent identifier	https://treatment.plazi.org/id/916887D7-7F6E-FF94-FF0D-0B8AFD17002A
treatment provided by	Plazi
scientific name	Micrurus tikuna
status	sp. nov.

Treatment

Micrurus tikuna sp. nov.

Figs. 1–2 View FIGURE 1 View FIGURE 2 .

Micrurus ornatissimus — Silva Haad 1994: 82.

Micrurus ornatissimus — Campbell & Lamar 2004; Plate 159.

Holotype. Adult female, MPEG 18199 (formerly Hospital Regional de Leticia-HRL 10101), collected by Juan Silva Haad, on 1991 at INCRA neighborhood, municipality of Tabatinga (04º14’36’’S, 69º54’15’’W; ca. 80 m above sea level, hereafter asl), state of Amazonas, Brazil ( Figs. 1–2 View FIGURE 1 View FIGURE 2 ).

Paratype. Adult male, ICN 10853, collected by Maria Cristina Ardila , (field number MC 8531), on November 23 1996 at Km 9.5 from Leticia-Tarapacá road, Quebrada La Arenosa (02º57’58’’S, 69º48’58’’ W, ca. 110 m asl), municipality of Leticia, department of Amazonas, Colombia.

Diagnosis. Micrurus tikuna can be distinguished from all congeners by the combination of the following characters: (a) white scales or a white transversal band posterior to parietal scales present; (b) dorsum of head black, forming a conspicuous cephalic-cap; (c) black nuchal collar absent; (d) ventral part of the head black with irregular white blotches followed by red scales on the gular region; (e) ventral scales 205 in the single male and 225 in the single female; (f) subcaudal scales 47 in the male and 38 in the female; (g) 27 to 31 black body rings in both sex (with 3 to 4 dorsal scales long) bordered by narrow, black tipped white rings (with 1/2 to one dorsal scale long), alternated by 27 to 31 wider red body rings (4 to 6 dorsal scales long); (h) tricolor tail with six to seven black rings (four to six dorsal scales long) bordered by narrow irregular white rings (1/2 dorsal scale long) alternated by six to seven red rings of the same length as the black rings; (i) lateral view of head with black coloration covering first four supralabials and postoculars and the last three supralabials, temporal and occipital regions red ( Figs. 1 – 2 View FIGURE 1 View FIGURE 2 ).

Comparison with other congeners from western Amazon ( Figs. 3–7 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 , Table 1 View TABLE 1 ). Twenty-four species of Micrurus are known to occur in western Amazon. Micrurus filiformis (Günther, 1859) , M. hemprichii ortoni Schmidt, 1953 , M. lemniscatus helleri Schmidt & Schmidt, 1925 , M. spixii spixii Wagler, 1824 , M. spixii obscurus Jan, 1872 , and M. surinamensis (Cuvier, 1817) are readily distinguishable from M. tikuna by their triadal pattern (vs. monadal pattern) ( Table 1 View TABLE 1 ).

Comparisons between Micrurus tikuna and the other 18 monadal species (including the two of the three currently recognized subspecies M. annellatus which present geographical distribution simpatric with M. tikuna ) are given below with meristic characters summarized in Table 1 View TABLE 1 (character states for M. tikuna are shown in parenthesis). M. albicinctus Amaral, 1925 , M. a. annelatus ( Peters, 1871), M. margaritiferus Roze, 1967 , M. medemi Roze, 1967 and M. putumayensis Lancini, 1962 ( Fig. 3 View FIGURE 3 ) differ from M. tikuna by having bicolor dorsal aspect on the body and tail (vs. tricolor dorsal aspect on the body and tail). Micrurus steindachneri steindachneri (Werner, 1901) , M. s. orcesi Roze, 1967 and M. petersi Roze, 1967 differ from M. tikuna by having cephalic-cap surrounded by red scales, yellowish rings on the body, and heavily melanic dorsum (vs. cephalic-cap surrounded by white scales; white rings on the body and tail; and light colored dorsum). Micrurus mertensi Schmidt, 1936 and M. peruvianus Schmidt, 1936 differ from M. tikuna by having bicolor tail, black nuchal collar, and white rings with two scales long (vs. tricolor tail; nuchal collar absent; and white rings with one scale long) ( Figs. 3 View FIGURE 3 J, 5B). Micrurus annellatus bolivianus Roze, 1967 differs from M. tikuna by having 15–24 black rings on the body, prefrontal scales completely black, white rings on body up to two scales long, and white transversal cephalic band (vs. 27–31 black body rings; white-spotted prefrontal scales; narrow white body rings 1/2 scales long; and absence of transversal white cephalic band) ( Fig. 5 View FIGURE 5 C). Micrurus averyi Schmidt, 1939 differs from M. tikuna by having head completely black, 8–12 black rings on the body, and bicolored tail (vs. black and white head; 27–31 body black rings; and tricolor tail) ( Fig. 5 View FIGURE 5 D). Micrurus catamayensis Roze, 1989 differs from M. tikuna by having black accessory rings isolating white rings from red rings on the body (vs. white rings contacting red rings) ( Fig. 5 View FIGURE 5 E). Micrurus langsdorffi (Wagler, 1824) differs from M. tikuna by having a black nuchal collar, yellow body rings, and red body rings up to four scales long (vs. absence of nuchal collar; white body rings; and red rings more than four scales long) ( Fig. 5 View FIGURE 5 F). Micrurus ornatissimus ( Jan, 1858) differs from M. tikuna by having black rings 2–3 and red rings 3–6 scales long on the body and tail, 32–66 black rings on the body, 3–15 black rings on the tail, and black nuchal collar (vs. black and red body rings with 4–6 and 4–8 scales long, respectively; 27–31 black rings, 6–7 black tail rings; and absence of black nuchal collar) ( Fig. 5 View FIGURE 5 G). Micrurus pacaraimae Carvalho, 2002 differs from M. tikuna by having a black nuchal collar, snout region stained with white, and red rings 8–12 scales long (vs. nuchal collar absent; snout entirely black; red rings 4–6 scales long) ( Fig. 5 View FIGURE 5 H). Micrurus paraensis Cunha & Nascimento, 1973 differs from M. tikuna by having a black nuchal ring, prefrontal scales completely black, and first white ring on the cervical region (vs. absence of black nuchal ring; white-spotted prefrontal scales; red cervical region, with first white ring far caudally placed beyond neck) ( Fig. 5 View FIGURE 5 I). Micrurus remotus Roze, 1987 differs from M. tikuna by having a mostly bicolor tail, black nuchal collar, entirely black prefrontal scales, and the region between cephaliccap and nuchal collar (vs. tricolor tail; absence of black nuchal collar; white spotted prefrontal scales; and region between cephalic-cap and nuchal collar uniformly red) ( Fig. 5 View FIGURE 5 J).

Description of the holotype ( Figs. 1–2 View FIGURE 1 View FIGURE 2 ). Adult female, 633 mm (SVL) and 66.5 mm (TL), tail length 9.5% of SVL; head length 17.11 mm, distinct from body, corresponding to 2.8% SVL; body slightly wider than high. Rostral shield visible from above (width 4.5 mm and length 2.3 mm); internasals wider than long; prefrontals wider than long, in contact with nasals, internasals, supraoculars, preoculars, and frontal; left prefrontal contacting both internasals; frontal pentagonal, nearly as long as wide, 1.5 times longer than its greatest width; parietal longer than wide, corresponding to 18.9% of head length; supraoculars longer than wide; nasal shield divided above nostril and below in contact with first two supralabials, internasals, prefrontals, and preocular; preocular in contact with supraocular, prefrontal, nasal, and third supralabial; two postoculars, upper postocular longer than lower; temporals 1+2; supralabial seven, with third and fourth bordering the orbit; infralabial seven, first pair in broad contact behind symphysial; first four infralabials contacting chinshields; posterior chinshields longer and wider than the anterior chinshields. Dorsal scales rows 15/15/15, smooth, without apical pits; three preventrals, ventrals 225, cloacal plate divided, and paired subcaudals 38.

Color Scales Coloration of the holotype in preservative ( Figs. 1–2 View FIGURE 1 View FIGURE 2 ). Dorsum of body with 31 black rings (three to four scales long) bordered by narrow black tipped white rings (four to six dorsal scales), alternated by 31 wider red rings (four to five scales long); tricolor tail with six black rings bordered by narrow irregular white rings, alternated by six red rings slightly narrower than black rings ( Fig. 1 View FIGURE 1 A); ventral surface of body and tail with immaculate red rings (four to five ventral scales long) ( Fig. 1 View FIGURE 1 B); head black dorsally (from rostral to first dorsal scale), forming a conspicuous black cephalic-cap; prefrontal scales with white spots posteriorly; white scales bordering posterior margin of black cephalic-cap; region between cephalic-cap and first white body ring red ( Fig. 2 View FIGURE 2 A); laterally, black coloration entirely covers first three supralabials, dorsal portion of fourth supralabial, and postocular scales; ventral portion of fourth to seventh supralabial red; temporal and occipital regions, towards the first white body ring, red with scales mostly black tipped ( Fig. 2 View FIGURE 2 C). Symphysial and first four infralabial scales black with irregular white markings; first pair of chin shields white with irregular black markings; second pair black with white spots on the anterior one-fourth. Gular region red mostly scattered with black spots ( Fig. 2 View FIGURE 2 B).

Color of the holotype in life ( Fig. 8 View FIGURE 8 ). The description of color in life was based on drawings and photographs from the holotype provided by Silva Haad (1994). Head with black cephalic-cap covering parietals, frontal, prefrontals, internasals, rostral, preoculars, postoculars and from first to fourth supralabial scales, may reach up to the first dorsal scales. Some specimens may have a narrow white strip separating this region's red hooded head post parietal. Prefrontal scales with white mark. Black cap separated from first white body ring by four to six dorsal scales. Laterally, head black from first to third supralabials and postocular, with black coloration including upper portion of fourth supralabial; head red from fourth supralabial until first white body ring, with most scales black tipped. In some specimens this red region is interrupted ventrally with prolonged white coloration on the gular region; anterior region of chinshields white, irregularly marked with black (including infralabial scales); posterior chinshields region mostly black; in some specimens red ring incomplete ventrally by invasion of white pigment on gular and first ventral scales; black body rings (three to four dorsal scales in length) followed by narrow white rings (0.5 scale in length) with black tipped scales and wider red rings (four to six dorsal scales in length); tricolor tail with black rings (four to six dorsal scales in length) followed by narrow white rings (0.5 scale in length), and red rings with same width or narrower than black rings. Ventrally red rings on the tail are incomplete.

Description of the paratype ( Fig. 9 View FIGURE 9 ). Adult male, 540 mm (SVL) and 94.5 mm (TL), tail length is about 14.8% of SVL; head length 16.64 mm, distinct from body, corresponding to 2.62% of SVL; frontal pentagonal, nearly as long as wide, 1.4 times longer than its greatest width, parietal longer than wide, corresponding to 21.3 % of the head length. Preventrals three, ventrals 205, and paired subcaudals 47. The other body and cephalic characters were invariable with respect to the holotype.

Hemipenis morphology (ICN 10853). Both hemipenes were everted in situ. Fully everted but partially expanded right hemipenis is slender, deeply bilobed and non-capitate. Sulcus spermaticus deep, bifurcated at base of lobes and running centripetally along lobes and reaching apexes; long lobes (about 40% of total hemipenial length), tapering distally into pointed tips; distal half of lobes ornamented by small to medium-sized spines densely arranged in irregular longitudinal rows, decreasing in size toward apex of lobes; proximal half of lobes less densely ornamented by dispersed larger and slender spines; lobular spines thinner and more numerous on the asulcate side of the organ; distal half of hemipenial body ornamented by small, irregularly arranged, spines, gradually increasing in size proximodistally; proximal region of hemipenis naked, except for presence of large basal pocket, extending along most of lateral surface of hemipenial body; asulcate surface of hemipenial body with spines restricted near lobes bifurcation.

Etymology. The specific epithet “ tikuna ” is a name in apposition derived from Tupi indigenous word “tacouma,” meaning a men with their face or nose painted with black ( Gregório 1980). Tikuna also refers to the native Indian nation that originally occupied the western Amazon region along the upper Solimões River near the boundaries between Brazil, Colombia and Peru. Similar to the Tikuna Indians, the new species of Micrurus has a head predominantly black.

Geographic distribution ( Fig. 10 View FIGURE 10 ). Micrurus tikuna is only known from Leticia, department of Amazonas, Colombia and Tabatinga, state of Amazonas, Brazil.