Cryptocellus iaci Tourinho, Lo Man-Hung & Bonaldo, 2010

Salvatierra, Lidianne, Tourinho, Ana Lúcia & Giribet, Gonzalo, 2013, Description of the male, larva and nymphal stages of Cryptocellus iaci (Arachnida, Ricinulei), with an overview of tarsal sensilla and other integumental structures, Zootaxa 3709 (2), pp. 149-161 : 151-156

Cryptocellus iaci Tourinho, Lo Man-Hung & Bonaldo, 2010

( Figs. 1–9 )

Type material examined: female holotype ( INPA 086), community of Caicubi (-1.0089º, -62.1196º), municipality of Caracaraí, state of Roraima, Brazil, visual nocturnal search, 25.x.2008, A.L. Tourinho leg.

New material examined: 1 larva ( INPA 087), 1 protonymph ( INPA 088), 1 deutonymph ( INPA 089), 1 tritonymph ( INPA 090) and 2 males ( INPA 0 91, 092) from “Bacaba” (-0.97799º, -62.10292º), community of Caicubi, municipality of Caracaraí, state of Roraima ( Brazil), leg. A.L. Tourinho, 25.v.2012, leaf litter sifting; 3 protonymphs, 3 tritonymphs (one leg used for DNA extraction) ( MCZ DNA 107039; IZ- 130037) from trail leading East of Caicubi (G. Giribet’s loc. 984: -1.02897º, -62.08722º), Rio Jufari, municipality of Caracaraí, Arquipélago de Mariuí e Baixo Rio Branco, Médio Rio Negro, Roraima ( Brazil), leg. L.R. Benavides, G. Giribet, G. Hormiga, 26.v.2012, leaf litter sifting; 1 male (on SEM stub), 1 female, 2 protonymphs, 1 deutonymph, 5 tritonymphs ( MCZ DNA 107040; IZ- 130038) from “Barreira Branca” (G. Giribet’s loc. 987: -1.01113º, -62.11409º), same locality and collection method, leg. O. Ferreira da Silva, L.R. Benavides, G. Giribet, G. Hormiga, W. Porto, A. Tourinho, 26.v.2012; 2 protonymphs ( MCZ IZ- 127855) from “Bacaba” (G. Giribet’s loc. 989: -0.97799º, -62.10292º), same locality and collection method, leg. L.R. Benavides, G. Giribet, G. Hormiga, 27.v.2012; 1 protonymph ( MCZ IZ- 127856), 1 male ( MCZ DNA 107041; IZ- 130039) from “Pupunha” (G. Giribet’s loc. 991: -0.98905º, -62.09831º), same locality and collection method, leg. G. Giribet, O. Ferreira da Silva, 28.v.2012; 1 protonymph, 2 females ( MCZ DNA 107042; IZ- 130040) from trail leading East of Caicubi (G. Giribet’s loc. 993: -1.02868º, -62.08985º), same locality and collection method, leg. L.R. Benavides, J. Ballesteros, G. Giribet, G. Hormiga, R. Indicatti, W. Porto, C. Rheims, 29.v.2012; 1 tritonymph ( MCZ IZ- 127857) [with a teratological right leg II: with an undivided tarsus (instead of 5 tarsomeres), but with a functional claw] from “Tucano” (G. Giribet’s loc. 997: -1.01460º, - 62.10589º), same locality, leg. L.R. Benavides, J. Ballesteros, T. da Silva, G. Giribet, G. Hormiga, 31.V.2012, on a tree trunk during night collecting by boat in inundated forest.

Revised diagnosis. Cryptocellus iaci can be readily recognized by the following combination of characters: carapace of male with tubercles concentrated in the grooves, forming five groups ( Fig. 6 ), one group positioned in lateral carapacal grooves, a group following the median line, and three groups on posterior margin of carapace ( Figs. 5 a, 6, 7c), female carapace virtually smooth, thus differing from those of C. abaporu , C. becki , C. foedus and C. simonis , which are tuberculate. At least two distinct tarsal pits lined by microtrichia present on male pedipalpal tibia ( Figs. 4 c, d), one dorsal and one lateral; females with proximal apophysis present dorsally on femur of leg I, blunt and as long as wide, apophysis present on leg II in males and females; proximal apophysis similar in size to that of C. abaporu , but not rounded as in the latter species (see Bonaldo & Pinto-da-Rocha 2003: fig. 14). The male resembles those of C. whitticki Platnick & Shadab 1977 and C. icamiabas in having a large concavity in the distal teleotarsus II of tarsus III, a large inner apophysis, and a large and rounded apophysis on trochanter IV. The female resembles that of C. becki (see Platnick & Shadab 1977: fig. 38) in having few tubercles on the cucullus, concentrated in the distal region ( Figs. 5 d, 7b), but differs in having the opisthosoma with two ventral pairs of shallow lateral pits containing tubercles, the anterior pair smaller than the posterior one. Spermathecae similar to those of C. simonis , but with ducts more coiled.

Description of male. Total body length, excluding pygidium, 5.63; cucullus length 0.73, greatest width 1.22; prosomal length 2.40, maximum width 1.97, between legs II and III; opisthosomal length 3.23, maximum width 2.42, near middle of tergite XI; legs I 0.61/ 0.56/ 1.64/ 0.47/ 0.96/ 1.06/ 0.64 (total: 5.9); leg II 1.16/ 0.44/ 1.85/ 0.77/ 1.69/ 1.81/ 1.72 (total: 9.44); leg III 1.11/ 0.31/ 0.69/ 1.39/ 0.68/ 0.91/ 1.15/ 1.70 (total: 7.9); leg IV 0.97/ 0.54/ 0.43/ 1.60/ 0.55/ 0.95/ 0.82/ 1.14 (total: 7.0).

General body color dark reddish-brown or black ( Figs. 2 , 3 , 4 ), prosomal venter lighter than dorsum, arthrodial membranes orange; cucullus dark red, darker at anterior margin and towards the middle. Type-11 tubercles present on DT I–IV, microtrichia present on DT I–IV ( Figs. 3 a, g) and covering all body ( Figs. 5 a, c, d). Cucullus with tubercles distributed as in Figs. 5 d and 7b. Opisthosomal tubercles mostly present on median tergites, sometimes absent on lateral tergites, tubercles concentrated in lateral concavity of median tergites and at their margins; intersegmental arthrodial membranes without tubercles ( Fig. 7 e). Legs densely covered with tubercles dorsally. Iridescent tubercles, showing shades of purple and blue, only present on opisthosomal venter. Surface of body entirely covered by two types of white setae, short and curved or long and straight ( Figs. 5 a–c). Prosoma longer than wide ( Fig. 5 a). Prosoma and opisthosoma covered with both long and short setae. Opisthosoma with high concentration of short, curved setae, appendages with short, curved setae more numerous than long, straight ones ( Fig. 5 c). Tergal tubercles concentrated on anterior lateral and central regions. One pair of lateral eye fields with translucent cuticle. Sternal region with coxae I not meeting tritosternum; left and right coxae II–IV meeting along midline; coxae IV free, not fused to coxae III ( Figs. 5 b, 7f). Pygidium with distal dorsal notch on basal segment; lacking ventral notch ( Figs. 5 c, 7e). Chelicerae small (880 µm long), with 4 or 5 large teeth on fixed finger and 7 large teeth on movable finger, covered by a brush of long plumose setae ( Fig. 4 a). Pedipalpi orange, without tubercles ( Figs. 4 b, c); long slit organ present on tibia ( Fig. 4 c); a dorsal and a lateral deep tarsal pit on tibia of pedipalpus ( Fig. 4 d), chela with 6 conspicuous teeth on fixed finger and 7–8 small teeth on movable finger (tarsus) ( Fig. 4 c). Pedipalpal setae uniform in shape ( Figs. 4 b–c). Leg formula II>IV>III>I. Tarsal formula 1,5,4,5. Sensillum of type 1 present on DT I–IV, a pair on DT-III; sensillum of type 2B absent; sensilla of types 3, 8, 9A and 10A present on DT I–IV; sensillum of type 9C present on DT III, pedipalpi and cucullus.

Description of larva ( Figs. 9 a, b). Carapace slightly longer than wide; cucullus and opisthosoma wider than long. Carapace and cucullus more densely covered with tubercles than adult. Body covered with fine translucent setae. Leg formula II>III>I. Tarsal formula 1,2,2. General body color (in 96% ethanol) pale yellow, opisthosoma yellowish-orange (dorsal and ventral view). Cucullus, legs, sternal region and pedipalpi pale yellow, tibia of pedipalpus light orange. Measurements (n = 1): total body length, excluding pygidium, 1.36; cucullus length 0.32, maximum width 0.41; prosomal length 0.71, maximum width 0.8, between legs II and III; opisthosomal length 0.61, maximum width 0.9, near anterior margin; leg I 0.29/ 0.14/ 0.30/ 0.16/ 0.23/ 0.31/ 0.13 (total: 1.56); leg II 0.38/ 0.19/ 0.48/ 0.25/ 0.31/ 0.40/ 0.37 (total: 2.38); leg III 0.31/ 0.16/ 0.15/ 0.16/ 0.34/ 0.17/ 0.25/ 0.16 (total: 1.7).

Description of protonymph ( Figs. 9 c, d). Carapace, cucullus and opisthosoma wider than long. Carapace and cucullus more densely covered with tubercles than larva; body covered with fine translucent setae, as in larva. Leg formula II>III>IV>I. Tarsal formula 1,4,3,2. General body color (in 96% ethanol) pale yellow, opisthosoma yellowish-orange (dorsal and ventral view). Cucullus, legs, sternal region and pedipalpi yellow; tibia of pedipalpus darker. Measurements (n = 1): total body length, excluding pygidium, 2.29; cucullus length 0.42, maximum width 0.54; prosomal length 0.89, maximum width 1.04, between legs II and III; opisthosomal length 1.42, maximum width 1.60, towards middle of tergite XI; leg I 0.40/ 0.16/ 0.43 /0.29/0.36/0.38 /0.21 (total: 2.2); leg II 0.54/ 0.25/ 0.70/ 0.35/ 0.42/ 0.65/ 0.64 (total: 3.6); leg III 0.46/ 0.29/ 0.25/ 0.49/ 0.28/ 0.35/ 0.32/ 0.28 (total: 2.7); leg IV 0.38/ 0.24/ 0.22/ 0.39/ 0.22/ 0.35/ 0.37/ 0.23 (total: 2.4).

Description of deutonymph ( Figs. 9 e, f). Carapace longer than wide; cucullus and opisthosoma wider than long. Carapace and cucullus densely covered with tubercles, body covered with fine translucent setae, as in the previous stages. Leg formula II>IV>III>I. Tarsal formula 1,5,4,4. General body color (in 96% ethanol) orange, arthrodial membranes of opisthosoma dark yellow (dorsal and ventral view). Cucullus and legs orange, sternal region dark yellow, pedipalpi pale yellow with distal segment orange. Measurements (n = 1): total body length, excluding pygidium, 3.35; cucullus length 0.59, greatest width 0.73; prosomal length 1.38, maximum width 1.27, between legs II and III; opisthosomal length 1.93; maximum width 2.02, towards the middle of tergite XI; leg I 0.61/ 0.36/ 0.59/ 0.44/ 0.37/ 0.46/ 0.22 (total: 3.1); leg II 0.73/ 0.37/ 1.03/ 0.54/ 0.98/ 0.95/ 0.86 (total: 5.5); leg III 0.67/ 0.27/ 0.33/ 0.66/ 0.47/ 0.50/ 0.47/ 0.47 (total: 3.8); leg IV 0.62/ 0.31/ 0.29/ 0.71/ 0.50/ 0.56/ 0.47/ 0.41 (total: 3.9).

Description of tritonymph ( Figs. 9 g, h). Carapace longer than wide; cucullus and opisthosoma wider than long. Carapace and cucullus with fewer tubercles than previous nymphal stages. Leg formula II>IV>III>I. Tarsal formula 1,5,4,5. Body covered with fine translucent setae. Coloration as in deutonymph. Measurements (n = 1): total body length (excluding pygidium) 4.97; cucullus length 0.78, greatest width 0.93; prosomal length 1.74, maximum width 1.66, between legs II and III; opisthosomal length 3.17, maximum width 2.97, towards the middle of tergite XI; leg I 0.72/ 0.47/ 0.98/ 0.51/ 0.71/ 0.86/ 0.34 (total: 4.6); leg II 0.94/ 0.53/ 1.32/ 0.87/ 1.12/ 1.47/ 1.36 (total: 7.6); leg III 0.78/ 0.37/ 0.51/ 0.90/ 0.61/ 0.56/ 0.46/ 0.82 (total: 5.0); leg IV 0.73/ 0.46/ 0.41/ 0.96/ 0.69/ 0.73/ 0.72/ 0.62 (total: 5.3).

Notes on biotope. See Tourinho et al. (2010) for details of the locality. All specimens were collected from leaf litter sifting, except for one specimen, which was collected on the trunk of a tree in an inundated forest and would not have been able to get to the soil without submerging in water.

Distribution. Known only from the type locality, in the state of Roraima, northern Brazil ( Fig. 1 ).

Figures

FIGURE 1. Type locality of Cryptocellus iaci: Community of Caicubi, municipality of Caracaraí, Roraima State, Brazil.

FIGURE 2. Cryptocellus iaci, live habitus: a, Male and deutonymph; b, Tritonymph; c, Male; d, Female.

FIGURE 3. Cryptocellus iaci, integumentary structures on legs of male MCZ IZ- 130038: a, Detailed view of sensilla of types 3 and 7, micropore, and microtubercles on tarsus of left leg II (scale bar = 10 µm); b, Type 9 A sensillum on tarsus III (scale bar = 100 µm); c, Type 11 tubercles surrounded by sensilla of types 5 and 10 A, and microtrichia on the proximal part on tarsus I (scale bar = 10 µm); d, Close-up of a type 2 A sensillum on tarsus I (scale bar = 10 µm); e, Detail of the ventral distal setae of type 9 C on tarsus II (scale bar = 20 µm); f, Type 8 sensilla on tarsus III (scale bar = 10 µm); g, Dome-like tubercles on tarsus II (scale bar = 10 µm); h, Micropore with microbarbs on tarsus of left leg II (scale bar = 2.5 µm); i, A pair of type 1 sensilla on DT III (scale bar = 10 µm). Abbreviations: Cr = curved seta with recurved fine tip, Cs = curved smooth seta with fine tip, DT = Dome-like tubercles, MM = micropore with microbarbs, Mic = microtrichia, ScM = Sculptured surface microtubercles, SM = Smooth surface microtubercles.

FIGURE 4. Cryptocellus iaci, left chelicera and pedipalpus of male MCZ IZ- 130038: a, Left chelicera, retrolateral view (scale bar = 100 µm); b, Left pedipalpus, prolateral view (scale bar = 100 µm); c, Detail of left pedipalpal claw, with mechanoreceptor long slit organs (*) (scale bar = 20 µm); d, Detail of guarded pit on left pedipalpal tibia (scale bar = 2 µm).

FIGURE 5. Cryptocellus iaci male MCZ IZ- 130038: a, Dorsal view of prosoma (scale bar = 200 µm); b, Sternal view of prosoma illustrating the separation of coxae IV from the other set of fused coxae and the large apophysis of trochanter IV (scale bar = 200 µm); c, Dorsal view of opisthosoma (scale bar = 200 µm); d, Cucullus (scale bar = 100 µm).

FIGURE 6. Cryptocellus iaci, male INPA 091: Prosoma, dorsal view. Scale bar = 100 µm.

FIGURE 7. Cryptocellus iaci, male INPA 091: a, Habitus, dorsal view (scale bar = 2 mm); b, Cucullus, frontal view (scale bar = 1 mm); c, Prosoma, dorsal view (scale bar = 1 mm); d, Right femur I showing apophysis, prolateral view (scale bar = 1 mm); e, Opisthosoma, dorsal view (scale bar = 1 mm); f, Whole body, ventral view (scale bar = 1 mm).

FIGURE 8. Cryptocellus iaci, male INPA 0 91, right leg III: a, Prolateral view; b, Retrolateral view; c – d, Spatular apophysis of basitarsus in retrolateral (c) and prolateral (d) views; e – g, Apophysis of tibia in retrolateral (e), anterior (f), and antero-lateral (g) views. All scale bars = 0.5 mm.

FIGURE 9. Cryptocellus iaci, larva and nymphal stages: a – b, Larva in dorsal (a) and ventral (b) views (scale bars = 0.5 mm); c – d, Protonymph in dorsal (c) and ventral (d) views (scale bars = 1 mm); e – f, Deutonymph in dorsal (e) and ventral (f) views (scale bars = 1 mm); g – h, Tritonymph in dorsal (g) and ventral (h) views (scale bars = 1 mm).