Microcaecilia rochai, Maciel, Adriano O. & Hoogmoed, Marinus S., 2011

Maciel, Adriano O. & Hoogmoed, Marinus S., 2011, Taxonomy and distribution of caecilian amphibians (Gymnophiona) of Brazilian Amazonia, with a key to their identification, Zootaxa 2984, pp. 1-53 : 23-26

Microcaecilia rochai sp. nov.

Holotype. MPEG 14596 ( Fig. 12 ), mature male, ( TL 187; PA 125; SG 51) from Reserva Pacanari (S 00°38’ W 52°34’), District of Monte Dourado, Municipality of Almeirim, State of Pará, Brazil, 4-XII-2001, collected by A. L. Prudente and R. R. Silva.

Paratypes. MPEG 14597, mature male, ( TL 113; PA 129; SG 49), same data as for holotype. IEPA /TQ 233, mature male, ( TL 227; PA 126; SG 51) from the Parque Nacional Montanhas do Tumucumaque (TQ), Igarapé Mapaoni, Municipality of Laranjal do Jari, State of Amapá, Brazil (N 2°11’ W 54°35’), January 2005 and IEPA /TQ 721, female ( TL 205; PA 122; SG 42), from the Parque Nacional Montanhas do Tumucumaque, Igarapé Mutum, Municipality of Pracuúba, State of Amapá, Brazil (N 1°23’ W 51°53’), between October and November 2005, both collected by Jucivaldo Lima.

Diagnosis. Maximum TL 227 mm. PA 122–129. SG 42–51. Eye not visible. PPT bicuspid; maxillary teeth extending posteriorly of choanae. Small terminal shield present, at most three annular grooves posterior to vent. Weak vertical keel may be present on terminus. Scales starting between PA 23 and 56.

Microcaecilia rochai sp. nov. differs from M. albiceps (Boulenger, 1882) , M. grandis Wilkinson, Nussbaum & Hoogmoed, 2009 , M. rabei ( Roze & Solano, 1963) , M. unicolor ( Duméril, 1863) , and M. iyob Wilkinson & Kok, 2010 in having more PA (122–129 versus 112–123, 121, 105–116, 107–117, and 97 respectively) and from M. supernumeraria Taylor, 1969 in having fewer PA and SG (122–129 and 42–51, versus 143 and 93); it has more SG than M. taylori Nussbaum & Hoogmoed, 1979 (42–51, instead of 0–21). Microcaecilia rochai sp. nov. is distinct from M. albiceps , M. unicolor , and M. supernumeraria in having bicuspid instead of monocuspid PPT.

Microcaecilia rochai sp. nov. is distinct from M. supernumeraria in having a small terminal shield, and distinct from M. taylori in having a smaller terminal shield. Microcaecilia rochai sp. nov. may have one to three annular grooves posterior to level of vent instead of at most one in M. taylori . Microcaecilia rochai sp. nov. differs from M. grandis by its smaller size, in not having the top of the head slightly convex, in not having concave upper jaw margins, in reaching higher PMT counts (31 in a specimen of TL 227 mm [IEPA/TQ 233] versus 29 teeth in the 318 mm holotype of M. grandis ), in having fewer PPT (maximally 22 instead of 28 in M. grandis ), in reaching higher DT counts (22 instead of 20 in M. grandis ), in having at most 6 rows of dermal scales per annulus, instead of 7–9 in M. grandis , and in having a scale inception of 23–56, instead of 12 in M. grandis ( Wilkinson et al., 2009) . For further comparisons see Table 9 .

continued next page Description. TL 35.7–48.3 times (41.1 ± 4.6; n = 4) BW. Head slightly narrower than body. Snout projecting distinctly beyond mouth. Eyes not visible, not even in smallest specimens. Nuchal grooves may be distinct dorsally, laterally and ventrally, except third groove which ventrally is incomplete; second nuchal collar ventrally partially fused with first primary annulus; a dorsal transverse groove on each collar, shorter and less distinct on first. Body subcylindrical, slightly wider than deep. Width along body may vary slightly. Primary annular grooves completely encircling body, except for at most three anterior annular grooves, which are ventrally incomplete, as well as some grooves at midbody and some interrupted by vent. At most 11 secondary grooves complete. Vent transverse, sometimes slightly irregularly shaped. AD 10–13; generally about as many on anterior as on posterior edge of vent (e.g. five anterior, five posterior in MPEG 14597). Paired anal papillae may be present; found in one of three male types, absent in the unique female type. Small terminal shield on posteriormost part of body; at most three annular grooves posterior to level of vent. Dermal scales start between annulus 23 and 56; at most six rows of dermal scales per fold. PMT monocuspid, maximally 31, with little variation in size, but posterior maxillary teeth slightly smaller, extending to level of posterior border of choanae or posteriorly beyond them. Maximally 22 bicuspid PPT with no apparent variation in size; smaller than PMT. DT monocuspid, maximally 22, approximately same size as PMT.

Colour. In preservative grayish or brownish with lateral and ventral surfaces of body slightly paler than dorsum. Grooves on sides of body may be slightly darker than general body colour.

Variation. For variation see description and Table 9 .

Distribution. Only known from localities where holo- and paratypes were collected in eastern part of Pará north of the Amazon and adjacent western Amapá, Brazil ( Fig. 13 ).

Etymology. The species is named in honor of Mr. Reginaldo Augusto Trindade Rocha, a technician in the herpetological laboratory of the Museu Paraense Emílio Goeldi for the past 25 years. He has participated in numerous fieldtrips throughout Amazonian Brazil and assisted many researchers and students.

Figures

FIGURE 12. Holotype of Microcaecilia rochai sp. nov. (MPEG 14596). Left column posterior part of body, laterally (above), dorsally (middle), and ventrally (below). Right column head, laterally (above), dorsally (middle), and ventrally (below). White bar represents 4 mm.

FIGURE 13. Distribution of Microcaecilia spp. in Brazilian Amazonia. Circles are M. taylori. Squares represents Microcaecilia rochai sp. nov. 1. Type locality of M taylori, Sipaliwini, Suriname; 2. Parque Nacional Montanhas do Tumucumaque, Igarapé Mapaoni, Laranjal do Jari, Amapá, Brazil; 3. Parque Nacional Montanhas do Tumucumaque, Pracuúba, Amapá, Brazil; 4. Holotype locality of M. rochai sp. nov. Reserva Pacanari, Almeirim, Pará, Brazil; 5. Caxiuanã, Melgaço + Portel, Pará, Brazil; 6. Vitória do Xingú, Pará, Brazil; 7. Tucuruí, Pará, Brazil; 8. Parauapebas, Pará, Brazil.

Tables

TABLE 9. Morphometric (in mm) and meristic data (range, mean ± standard deviation and sample size in parenthesis) of Microcaecilia spp. from Brazilian Amazonia.

	M. rochai sp. nov.	M. taylori
TL	113–227 183±42.8 (4)	77–225 169.7±48.2 (120)
HW	3–4.4 3.9±0.5 (4)	2.6–4.7 3.7±0.8 (122)
HL	3.9–6.2 5.4±0.9 (4)	3.7–7 5.3–1.1 (122)
HH	2.6–3.6 3±0.3 (4)	1.8–4.2 2.8±0.7 (121)