(Figs. 1–14)
Types. Male holotype from Parque Estadual da Cantareira (23° 25’ S; 46° 37’ W), São Paulo, São Paulo, Brazil, 12–17.V.2005, F. Yamamoto col. with pitfall traps, deposited in IBSP 61393. Paratypes: 1 female (IBSP 62402); 1 male and 1 female (IBSP 62404); same data as holotype, 14–19.XI.2004.
Etymology. The species name is a noun in apposition, derived from the Latin word for jar, in reference to the jar (cântaro) commonly used to carry and store water from streams and riverheads in the 16 th and 17 th centuries at the type locality.
Diagnosis. The male is distinguished from the congeners by the shape of the cheliceral apophyses (large with a curved end: Figs. 3–5) combined with the shape of the procursus, very curved (Figs. 6–7) and the tip with a prolateral projection (Fig. 7) and a retrolateral membranous projection (Fig. 8). The female is distinguished by the projecting epigynum with a rounded, relatively large and shallow epigynal pocket (Fig. 12).
Description. Male (Holotype). Total length 2.4, carapace width 1.0; leg I: 18.2 (5.0 + 0.4 + 5.2 + 6.3 + 1.3), tibia II: 2.5, tibia III: 2.1, tibia IV: 3.1, tibia I L/d: 40. Habitus as in figs. 1–2. Carapace light brown, very similar in shape to M. forceps Machado, Brescovit, Candiani & Huber, 2007; sternum light ochre. Distinct thoracic groove. Eight eyes on slightly elevated ocular area (Fig. 2); distance PME–ALE about 60% of PME diameter. Chelicerae light brown, basal segment with a pair of large parallel frontal apophyses with strongly curved ends (Figs. 3–5). These apophyses are approximately perpendicular to the chelicerae (Fig. 3). Palps as in figs. 6–10. Coxa with prominent and approximately rectangular retrolateral apophysis (Fig. 6). Femur proximally with distinct round retrolateral apophysis and small proximal dorsal hump (Fig. 6). Procursus dark brown, strongly curved proximally, with strong proximal-prolateral hair (Figs. 6–7). Distinct tip of procursus, enlarged laterally and strongly sclerotized, with a prolateral apophysis (Figs. 7–8) and a retrolateral semitransparent membranous projection (Figs. 6–8). Bulb with small transparent projection (Figs. 9–10), embolar division of bulb long and dorsally bent, membranous ventrally. Legs light brown; without spines, vertical or curved hairs. Tarsus I with approximately 24 pseudosegments. Opisthosoma globular, pale green, with several lateral bluish-green spots (Figs. 1–2).
Female (Paratype IBSP 62402). Total length 2.4, carapace width 0.93; leg I: 10.4 (1.4 + 0.4 + 3.1 + 4.4 + 1.1), tibia II: 2.0, tibia III: 1.6, tibia IV: 2.6, tibia I L/d: 28. Habitus as in fig. 1. In general very similar to male. Epigynum dark brown, elevated, ventral region bulging, with rounded and shallow medium-sized median pocket, without apophyses or humps (Figs. 11–13), with two pairs of short and strong hairs on membranous area behind gonopore (Fig. 13). Internal genitalia with two pore plates, longer than wide (Fig. 14).
Variation. Three males: carapace width 0.9–1.0; tibia I: 4.2–5.2. Two females: carapace width 0.93; tibia I: 3.1–3.3.
Other material examined. Brazil, São Paulo: São Paulo (Parque Estadual da Cantareira, 23° 25’ S; 46° 37’ W), 1♂, 14–19.XI.2004 (IBSP 62405); 1♂, 12–17.V.2005 (IBSP 62406).
Distribution. Known only from type locality.