Amazochroma carvalhoi, gen. et comb. nov.
Creators: name: Rafael N. Carvalho
name: Adriano B. Kury
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Opiliones
Gonyleptidae
Amazochroma
Amazochroma carvalhoi

description: Amazochroma carvalhoi (Mello-Leitão, 1941) gen. et comb. nov.
Figs 1 A–D, 5–6
Discocyrtus carvalhoi Mello-Leitão, 1941: 437.
Discocyrtus carvalhoi – Soares & Soares 1954: 247; Kury 2003: 161.
Material examined
Holotype
BRAZIL: ♂, MT, Santa Terezinha, Barra do Tapirapé, 10.683° S, 50.633° W, A.L. Carvalho leg. (MNRJ 5143).
Other material examined
BRAZIL: 1 ♀, AM, Manaus, Reserva Florestal ZF-3, 2.21° S, 59.81° W, Reserva do km 41, 28–31 Jul. 2002, G. Machado leg. (MNRJ 9067); 1 ♂, 1 ♀, PA, Belém, Parque Ambiental de Belém (Utinga), 1.424827° S, 48.438016° W, Feb. 2010, G.H.F. Azevedo et al. leg. (UFMG 9382); 1 ♀, PA, Monte Alegre, Instituto de Pesquisas Ecológicas da Amazônia (IPEAm), 0.84467° S, 54.45327° W, 1970, Mário leg. (MNRJ 8811).
FRANCE: 1 ♂, French Guiana, Arrondissement of Saint-Laurent-du-Maroni, Commune de Maripasoula, Monts Atachi Bakka, 3.54463° N, 53.91278° W, 632 m asl., 6 Feb. 2015, S. Cally leg. (MNRJ 8801); 1 ♂, 1 ♀, French Guiana, Arrondissement of Saint-Laurent-du-Maroni, Commune de Maripasoula, Monts Atachi Bakka, 3.56714° N, 53.96177° W, 127 m asl., 8 Feb. 2015, S. Cally leg. (MNRJ 8799).
SURINAME: 1 ♀, Sipaliwini District, Apalagadi Mounts, 2.17064° N, 56.09961° W, 16 Apr. 2014, A. Fouquet and J.P. Vacher leg. (MNRJ 8800); 1 ♂, Sipaliwini District, Apalagadi Mounts, 2.17064° N, 56.09961° W, SR 140416 HC001-22, 16 Apr. 2014, A. Fouquet and J.P. Vacher leg. (NZCS); 1 ♀, Sipaliwini District, Apalagadi Mounts, 2.17064° N, 56.09961° W, SR 140416 HC001-23, 16 Apr. 2014, A. Fouquet and J.P. Vacher leg. (NZCS).
Etymology
Patronymic in honor of Brazilian zoologist Antenor Leitão de Carvalho (1910–1985), who collected the holotype of this species.
Diagnosis
Spines of ocularium higher than in Amazochroma pedroi gen. et sp. nov. (Fig. 5C); areas II–IV not divided by a median groove (divided in A. pedroi gen. et sp. nov.) (Fig. 5A); area III with a pair of high, paramedian acuminated spines curved backwards (higher than the pair of low, paramedian rounded, tubercles of A. pedroi gen. et sp. nov.) (Fig. 5B, D); Cx IV with retrodorsal spiniform apophysis (absent in A. pedroi gen. et sp. nov.) (Fig. 5A); Tr IV with prolateral, distal, higher apophysis, forming a bifurcated bar ending in two spines (instead the aborted hook form in A. pedroi gen. et sp. nov.) (Fig. 5A); Fe IV without spines, only tubercles (instead of higher spines on the prolateral and retrolateral axes of A. pedroi gen. et sp. nov.) (Fig. 5E–H).
Redescription
Holotype (male)
MEASUREMENTS. CW 3.3, CL 2.0; AW 6.1, AL 3.6. Leg measurements in Table 3, tarsal counts in Table 4.
DORSUM. Dorsal scutum almost as long as wide, abdominal scutum with lateral margins strongly convex, widest at area II and highest at area III (Fig. 5A, D). Carapace with several tubercles on posterior region (Fig. 5A, D). Cheliceral sockets shallow, with a small apophysis in the center. Ocularium elliptical, high, inclined frontwards, placed in middle of carapace, armed with a pair of divergent high spines fused at baseline and inclined frontwards (Fig.5A, C–D). Mesotergum divided into four clearly defined areas. Area I divided into left and right halves by median groove. Area II anterior lateral border invading slightly space of area I and posterior lateral border invading the space of area III. AS lateral borders with tubercles on full extent, gradually growing to height of area III. All areas with many tubercles. Area I with a pair of paramedian tubercles higher than the others. Area II with one main transverse row of tubercles, replaced in middle by two pairs (one anterior and one posterior) of moderate-sized tubercles forming a trapezoid. Besides those, several others minor tubercles. Area III with a pair of high paramedian acuminated spines curved backwards, with the base covered by small tubercles (Fig. 5A–B, D). Area IV with horizontal row of 3 highlighted tubercles. Posterior border of dorsal scutum and free tergites with a horizontal row of tubercles with same height as highlighted on area IV.
VENTER. Cx I–III parallel to each other; each with ventral transverse rows of 9–10 setiferous tubercles (Cx I main row with higher and sharper tubercles). Cx IV much larger than the others, directed obliquely. Stigmatic area Y-shaped, clearly sunken relative to distal part of coxa IV. Intercoxal bridges well marked. Stigmata clearly visible. Free sternites and anal operculum each with a transverse row of small tubercles.
CHELICERA. Basichelicerite elongate, bulla well marked, with marginal setiferous tubercles – three ectal, three posterior, one mesal and one dorso-basal; hand not swollen (Fig. 5A).
PEDIPALPUS. Tr with two dorso-ectal, dorso-mesal and medio-ventral setiferous tubercles. Fe with one meso-distal and one mesal ventro-basal setiferous tubercles. Pa with one meso-distal setiferous tubercle. Ti with two rows of setiferous tubercles; four (IiIi) ventro-mesal and four (Iiii) ventro-ectal, of which the two distal are geminated. Ta with two rows of setiferous tubercles; three (IIi) ventro-mesal and four (IiIi) ventro-ectal.
LEGS. Tr I–III each with several ventral tubercles. Fe I and II straight. Fe I retrolateral proximal tubercle higher than the others, not forming a spur. Tr I with prodorsal, proventral, retroventral and retrodorsal rows of small tubercles. Fe II with prodorsal, prolateral, proventral, retroventral, retrolateral and retrodorsal rows of small tubercles. Fe II with a small retrodorsal distal tubercle higher than the others, not forming a spur. Tr II with prodorsal, proventral, retroventral and retrodorsal rows of small tubercles. Fe III substraight. Fe III and Ti III with prodorsal, prolateral, retrolateral and retrodorsal rows of small tubercles, with proventral and retroventral rows of tubercles gradually growing to the distal portion. Fe III and Mt III with a well-developed retrodorsal distal spur. Posterior border of Cx IV not reaching longitudinally the posterior border of dorsal scutum. Cx IV with a prolateral apical caniniform apophysis, moderately elongate and a retrodorsal spiniform apophysis (Fig. 5A). Cx IV with prodorsal, prolateral and proventral rows of tubercles. Tr IV prolaterally with three conical apophyses: two proximal, unequal ones and one distal, longer, bifurcated. Tr IV distally and retrolaterally with one spearhead apophysis. Tr IV ventrally with several tubercles along its entire length. Fe IV substraight, curved from the medial region toward dorsal. Fe IV with prodorsal, prolateral, retroventral and retrodorsal rows of small tubercles, dorsal tubercles only in proximal portion (Fig. 5E–H). Fe IV prodorsally (entire length) and retrolaterally (proximal-medial portion) with a row of setiferous tubercles (Fig. 5E–F, H). Fe IV proventrally and retrodorsally with one distal spine forming a spur (Fig. 5E–H). Pa IV covered by tubercles in dorsal view; also with proventral and retroventral rows of three tubercles each. Ti IV with prodorsal, prolateral, proventral, retroventral, retrolateral and retrodorsal rows of tubercles. Ti IV with proventral and retroventral distal spurs. Tarsal counts: 6(3)-6(3)/9(3)-9(3)/7-7/7-7.
PENIS. VP sharply divided into two regions: distal part rectangular, proximal part elliptical (Fig. 6A–C). Ventral surface of VP entirely covered with microsetae of type 1 (Fig. 6C). All macrosetae inserted on lateral of VP: A1–A3 cylindrical, thick, on basal third of VP, A1 oriented dorsally, A2 oriented sidewards, A3 oriented ventrally (Fig. 6A–E); B1 inserted ventrally, below the line of A3 (Fig. 6C–D); C1–C3 slender, only moderately elongate, forming an almost longitudinal row on the distal part of VP, C1–C2 close together on distal portion, C3 on medial basal portion (Fig. 6A–E); D1 medium, midway between C3 and A1 (Fig. 6A–E); E1–E2 inserted ventrally, E1 between the height of C1–C2, E2 beside C3 (Fig. 6C–D). Glans sac long, arising from middle bulge on podium, extended as a dorsal process to height of central sinuosity of stylus (Fig. 6A–B, D–E). Stylus stout, cylindrical and S-curved to dorsal, without any processes (Fig. 6A–B, D–E). Apex of stylus flattened dorsoventrally, with three barbs on each side, one on middle of ventral portion, two on marginal part of medium-basal ventral portion (Fig. 7F–G).
COLOR (in vivo). Color background of scutum, coxae and trochanters Strong Reddish Brown (40), with spines of ocularium, paramedian tubercles of areas I and III and main apophyses of coxae and trochanter IV Brownish Black (65). Dry marks Very Pale Purplish Blue (202), distributed on Cx and Tr I–IV, free tergites I–III and all over dorsal scutum encircling tubercles, excepted in two crescent-shaped stripes extending from carapace to area III. Chelicerae, pedipalps (glossier than legs) and most of legs I–IV (excepting femora) Strong Yellow (84). Femora 3-banded: basal 40% as scutum, median 50% as apophyses and distal 10% as rest of legs.
VARIATION. Besides the variation in tarsal counts, shown in Table 4, the distribution and development of tubercles, apophyses and spines in our sample was fairly uniform. No minor (“beta”) males were detected.
Female (MNRJ 8811)
CW 4.2, CL 2.7; AW 7.6, AL 4.7. Cx IV with much weaker armature compared to male, main apophysis reduced to a simple spine. Fe IV thinner, less curved and armed when compared to male. Fe IV with fewer spines on distal proventral axis and a retrolateral distal spur.
Distribution
BRAZIL, Amazonas (NT 0 173 – Uatuma-Trombetas Moist Forests), Mato Grosso (NT 0 140 – Mato Grosso Seasonal Forests), Pará (NT 0 170 – Tocantins-Pindaré Moist Forests); FRENCH GUIANA, Maripasoula; SURINAME, Sipaliwini (NT 0 125 – Guianan Moist Forests) (Fig. 2).
Remarks
This species was described in Discocyrtus, and never illustrated. In a catalogue of the Pachylinae, Soares & Soares (1954) merely listed the name. Its generic assignment has never been challenged.
description: Published as part of Rafael N. Carvalho & Adriano B. Kury, 2018, Further dismemberment of Discocyrtus with description of a new Amazonian genus and a new subfamily of Gonyleptidae (Opiliones, Laniatores), pp. 1-32 in European Journal of Taxonomy 393 on pages 17-22, DOI: 10.5852/ejt.2018.393, http://zenodo.org/record/1143721