Ityphilus bonatoi

Description. Female holotype. Forty-one leg-bearing segments, body length 13 mm. Trunk attenuate in anterior and posterior regions. Width of selected leg-bearing segments as follows: 1 (0.30 mm); 2 (0.30 mm); 3 (0.28 mm); 6 (0.32 mm); 12 (0.40 mm); 18 (0.45 mm); 22 (0.49 mm); 27 (0.51 mm); 32 (0.48 mm); 38 (0.39 mm); 40 (0.33 mm); 41 (0.36 mm). Width of cephalic plate 0.32 mm. Width of forcipular coxosternite 0.32 mm. Ground color (of preserved specimen in alcohol) pale ocher. Antennae. About 2.6 times as long as the cephalic plate, conspicuously geniculate, distally clavate (Figs. 53, 54). Basal a. a. slightly overlapping medially (Fig. 62). Ratio of width of a. a. X (= widest a. a. of distal antennal half) / width of a. a. V (= narrowest a. a. of basal antennal half) 1.66: 1. Apical club extending over a. a. IX to XIV, a. a. VIII transitional, being narrow basally and widened distally (Figs. 1, 2). A. a. XIV apically blunt, shorter than the three previous a. a. taken together (ratio of length of a. a. XIV / length of a. a. XI – XIII, ca. 0.87: 1). Length / width ratio of left a. a. I – XIV (in dorsoventral position) as follows: I (0.69: 1); II (0.77: 1); III (0.80: 1); IV (0.88: 1); V (1.04: 1); VI (0.86: 1); VII (0.56: 1); VIII (0.35: 1); IX (0.28: 1); X (0.29: 1); XI (0.36: 1); XII (0.37: 1); XIII (0.40: 1); XIV (1.35: 1). Ventral chaetotaxy: setae on a. a. I to VIII of various lengths, and relatively few in number, those of a. a. IX to XIV much shorter and very numerous (Fig. 53). Dorsal chaetotaxy: setae on a. a. I to VIII similar to those on ventral side, setae on a. a. IX to XIV much longer and less numerous than those on ventral side (Fig. 54). A. a. XIV with ca. 11 claviform sensilla on the external border, and ca. 6 on the internal border (Fig. 55); distal end of this a. a. with ca. 11 very small hyaline specialized sensilla apparently not split apically (Fig. 55). Ventral and dorsal surface of a. a. II, V, IX, and XIII with very small specialized sensilla. Ventrally, specialized sensilla distributed apically (Figs. 56, 57), and represented by two different types: a and b. Type a sensilla very thin and not split apically (Fig. 56: a); type b sensilla (Fig. 56: b) very similar to those on the apex of a. a. XIV. Specialized sensilla on dorsal side distributed apically (Figs. 58 – 60) and represented by three different types: a and b similar to a and b of ventral side (Fig. 60: a, b), and type c sensilla “ spine-like, larger, not divided apically, and slightly darker (pale brownish – ochreous) (Fig. 60: c). Number and distribution of specialized sensilla on ventral and dorsal sides of a. a. II, V, IX, and XIII as in Table 3. Cephalic plate. About as wide as the forcipular tergite; slightly wider than long (width / length ratio, 1.13: 1); shape and chaetotaxy as in Figure 61. Clypeus. With 7 + 5 setae distributed as in Figure 62. Labrum. Poorly pigmented; mid-piece membranous, smooth, slightly concave; sidepieces with 2 + 2 diminutive sharply pointed denticles (Fig. 63). Mandibles. Dentate lamella not subdivided into blocks, 9 teeth in the right mandible (Fig. 64), 7 teeth in left mandible; pectinate lamella with ca. 17 hyaline teeth. First maxillae. Coxosternite apparently without lappets, telopodites bearing lappets (Fig. 65). Coxosternite devoid of setae; coxal projections subtriangular, round tipped and provided with 1 + 1 setae (Fig. 65). Telopodites without visible suture between presumptive basal and distal articles, ventral surface with 1 + 1 setae near the central part of the medial edge (Fig. 65), dorsal surface with 1 + 1 sensilla. Second maxillae. Coxosternite without any trace of suture along the sagittal plane and provided with 4 + 5 setae arranged as in Figure 65. Apical claw of telopodites well developed, bipectinate, dorsal and ventral edges with 7 teeth (Figs. 66, 67). Forcipular segment. When closed, telopodites not reaching the anterior margin of the head (Fig. 61). Forcipular tergite slightly wider than the tergite of the first leg-bearing segment (ratio 1.10: 1), chaetotaxy represented by two irregular transverse rows each of ca. 11 – 13 setae (Fig. 61). Coxosternite: with complete chitinlines (Fig. 68: a); maximum width / length at the middle ratio, 1.83: 1; central part of anterior margin as in Figure 68. Telopodites: all articles without teeth; trochanteroprefemur with greatest length / greatest width 1.12: 1; internal edge of tarsungula expanded inwards, bearing 6 – 7 strong teeth occupying the middle and apical thirds (Figs. 68 – 70). Calyx of poison gland with shape and relative size as in Figures 69, 70. Shape and chaetotaxy of coxosternite and telopodites as in Figure 68. Tergites. Surface of pretergites and metatergites smooth, sulci not evident. Sternites of leg-bearing segments 1 to penultimate. Pore-fields present in an uninterrupted series from sternite 2 to penultimate (40) inclusive. All pore-fields undivided and located on raised prominences. Form and relative size of pore-fields changing along the trunk as in Figures 71 – 93. Number of pores on selected sternites as follows: sternite 2 (7); 4 (26); 5 (34); 8 (52); 9 (64); 12 (72); 13 (76); 14 (66); 15 (71); 16 (70); 17 (72); 18 (64); 20 (57); 23 (45); 26 (29); 27 (28); 31 (16); 35 (13); 36 (12); 37 (6); 38 (4); 39 (3); 40 (2). Legs (pair 1 to penultimate). First pair slightly shorter than second pair (ratio 0.90: 1), aspect and relative size as in Figures 94, 95. Chaetotaxy of legs similar throughout the entire body. Distribution, number and relative size of setae as in Figures 94 – 99. Claws with three thin pale accessory spines ventrobasally, arrangement and relative size as in Figure 100. Ultimate leg-bearing segment. About 1.10 times as wide as the penultimate; intercalary pleurites present at both sides of ultimate pretergite; ultimate presternite divided along the sagittal plane; length / width ratio of tergite 0.72: 1; length / width ratio of sternite 1.0: 1. Shape and chaetotaxy of tergite and sternite as in Figures 102, 103. Coxopleura very slightly protruding at distal-internal ventral ends, setae distributed on almost the whole ventral and lateral surfaces, dorsal side with setae on the external half only (Figs. 102, 103). Two single (“ homogeneous ”) coxal organs in each coxopleuron, the anterior being smaller than the posterior, shape as in Figure 105. Coxal pores opening on the membrane between coxopleuron and sternite, partially covered by the latter (Fig. 105), internal cuticular structure of coxal organs as shown in Figure 105 (a: mucous layer). Ultimate legs with seven articles. Articles strongly thickened, subconically narrowing from base to distal end, width of trochanter / width of tarsus 2 ca. 2.66: 1. Length of telopodites of ultimate legs / length of sternite 1.71: 1. Length of telopodites of ultimate legs / length of legs of the penultimate pair 0.72: 1. Shape and chaetotaxy of ultimate legs as in Figures 102, 103. Postpedal segments. Intermediate tergite with posterior margin convex (Fig. 102); intermediate sternite with posterior margin straight to very slightly convex, posterior margin of first genital sternite slightly concave in midline (Fig. 103). Gonopods uniarticulate, without setae (Fig. 103).

Diagnosis. An Ityphilus species with internal edge of forcipular tarsungulum serrate. Among the other Neotropical members of the genus having the same trait it only shares with I. donatellae Pereira, 2012 a very small body size and a low number of leg-bearing segments. Ityphilus bonatoi sp. nov. can be differentiated from I. donatellae by means of the following selected traits (the corresponding traits in the latter are given in parentheses): body length of the female 13 mm (female: 11 mm, male: 8.5 mm); female with 41 leg-bearing segments (female with 43, male with 41); shape of the antennae as in Figures 53, 54 (as in Figure 107); a. a. XIV conspicuously longer than wide, length / width ratio ca. 1.34: 1 (about as wide as long); a. a. XIV shorter than a. a. XI – XIII taken together, ratio ca. 0.87: 1 (a. a. XIV longer than a. a. XI – XIII taken together, ratio ca. 1.25: 1); shape of type c sensilla on dorsal side of a. a. IX and XIII as in Figure 60: c (as in Figure 108: c); internal edge of forcipular tarsungulum expanded inwards bearing 6 – 7 strong teeth occupying the middle and apical thirds, Figs. 68 – 70 (internal edge of forcipular tarsungulum not expanded inwards bearing ca. 7 small teeth occupying the middle third, Fig. 109); shape of pore-fields as in Figures 71 – 93 (as in Figures 110 – 117); sternite 5 with ca. 34 pores, 8 (ca. 52), 17 (ca. 72), 27 (ca. 28) (sternite 5 with ca. 21 pores, 8 (ca. 30), 17 (ca. 24), 27 (ca. 9 )).

Remarks. I. bonatoi can be separated from all the other Neotropical species of Ityphilus with internal edge of forcipular tarsungulum serrate, by using the key presented below. For characters differentiating I. bonatoi from other Neotropical species of Ityphilus, see Discussion below.

Remarks. The adult condition of the female holotype is indicated by the presence of spermatozoa in both spermathecae (Fig. 103: a).

Etymology. The species is dedicated to my distinguished colleague Lucio Bonato (Dipartimento di Biologia, University of Padova, Italy) in recognition of his extraordinary skill, dedication, and hard work as a leader in analysing and establishing a common terminology for the external anatomy of all centipede orders.

Type locality. BRAZIL: RJ: Ilha Grande, Enseada das Palmas. Known range. Only known from the type locality.

Type material examined: BRAZIL: RJ: Ilha Grande, Enseada das Palmas, 2 – 12 February 1997, M. J. Ramírez leg.: holotype female, 41 leg-bearing segments, body length 13 mm. Depository of type: MZUSP.