Eusarcus pusillus Sørensen

Hara, Marcos Ryotaro & Pinto-Da-Rocha, Ricardo, 2010, Systematic review and cladistic analysis of the genus Eusarcus Perty 1833 (Arachnida, Opiliones, Gonyleptidae) 2698, Zootaxa 2698, pp. 1-136 : 94-97

Eusarcus pusillus Sørensen

( Figs. 29, 42C,D, 50B)

Eusarcus pusillus Sørensen 1884: 624 (key), 625; Mello-Leitão 1945: 155 (cat), 156 (cit); Soares & Soares 1954b: 261

(cat); Kury 2003a: 170 (cat); (2 fe syntypes; “ Rio de Janeiro; Reinhardt leg.; ZMUC”; examined from pictures). Eusarcoides pusillus: Roewer 1913: 73 (rdesc); 1923: 420 (rdesc); Mello-Leitão 1923b: 122 (cat); 1932: 162 (rdesc). Eusarcus vervloeti B. Soares 1944c: 145 (cit), 152, figs. 7, 8; Mello-Leitão 1945: 156 (cat), 157 (key), fig. 22; B. Soares

1946: 520 (cat); Soares & Soares 1946a: 202 (syst); 1954a: 496 (syst, diag); 1954b: 262 (cat); Kury 2003a: 170

(cat); (ma holotype & 1 fe “ allotype ”; “Chaves, Santa Leopoldina, Espírito Santo, Brazil; B.A.M. Soares leg.;

28.viii.1942; MZSP 286”; examined). Syn. n. Eusarcus hastatus : [misid] B. Soares 1945c: 375 (cat [pars]); Soares & Soares 1946a: 196 (cit). Eusarcus oxyacanthus : [misid] B. Soares 1945c: 376 (cat [pars]); Soares & Soares 1946a: 196 (dist).

Material examined: BRAZIL. Rio de Janeiro: Reinhardt leg., without date, 2 fe syntypes ( ZMUC); examined from pictures. Espírito Santo: Santa Leopoldina (Fazenda Chaves) , B.A.M. Soares leg., 28.viii.1942, ma holotype & 1 fe “ allotype ” of E. vervloeti ( MZSP 286). Bahia: Una, A.D. Brescovit et al. leg., 13–16.iv.1998, 1 fe ( IBSP 2293). Espírito Santo: without name of collector and date, 1 ma & 2 fe ( MNRJ 102); Colatina, M. Rosa leg., 1 fe ( MNRJ); Linhares, Schubart leg., 20.x.1944, 1 fe ( MZSP 1741); idem (Reserva Florestal Vale do Rio Doce), A. & M. Peracchi & B.O. Fraga leg., 6.xii.1978, 2 fe ( MNRJ 4554); idem (Fazenda Goitacazes), M. Rosa leg., without date, 1 ma ( MNRJ 58215); Santa Leopoldina, 1942, 4 ma ( MZSP 287); idem, 3 ma & 4 fe ( MZSP 288); idem, 3 ma & 2 fe & 2 im ( MZSP 557); idem, 29.viii.1942, 2 ma, 3 fe & 6 im ( MZSP 548); idem, ix.1942, 1 ma ( MZSP 559); idem, F.J. Vervloet leg., 10.iii.1945, 2 ma & 2 fe ( MZSP 1736); idem, F.J. Vervloet & R.H. Vervloet leg., x.1945, 2 ma & 2 fe ( MZSP 1737); idem, Vervloet leg., 1944– 1945, 3 fe ( MZSP 1718); idem, B.A.M. Soares leg., 29.viii.1942, 1 ma & 2 fe ( MZSP 554); Santa Teresa, J. Schubart leg., 2.xi.1944, 1 ma ( MZSP 1744); idem (Cachoeira São Lourenço), J. Schubart leg., 2.xi.1944, 1 fe ( HEMS 1003); idem, J. Schubart leg., 2.xi.1944, 1 ma & 1 im ( HEMS 1002); idem (Penha), Schubart leg., 30.x.1944, 1 ma ( HEMS 1001); idem, without name of collector, vii.1951, 1 ma & 1 fe ( HEMS 269); Vitória (Convento da Penha), A. Ruschi leg., 12.vi.1965, 1 fe ( MNRJ 6046). Rio de Janeiro: Araruama (Juturmaiba), C. Alvarenga et al. leg., xi.1978, 1 ma & 1 fe ( MNRJ 5879); Cachoeiras de Macacu, A.B. Kury & R. Pintoda-Rocha leg., 8.x.1988, 1 ma & 1 fe ( MNRJ 6308); idem, (Reserva Estadual Guapiaçu), R. Baptista et al. leg., 11.iii.2001, 4 ma & 4 fe ( MNRJ 14302); Casimiro de Abreu (Barra de São João), Exp. Arachné leg., 21– 24.iii.2003, 6 ma & 4 fe ( MNRJ 17555); idem (Barra de São João, Fazenda Reunidas), A.B. Kury leg., 16.x.1988, 1 ma & 2 fe ( MNRJ 6345); Macaé (APA SANA), D.C. Pedroso & A. Pérez leg., 19–21.vii.2002, 1 fe ( MNRJ 11364); Magé (Pau Grande), H. Berla leg., without date, 1 ma & 3 fe ( MNRJ 5254); idem (Citrolândia), A.B. Kury leg., 15.x.1988, 1 fe ( MNRJ 6338); Nova Iguaçu (Tinguá), Lamartine leg., viii.1954, 1 beta male (removed from MNRJ 16142); Nova Friburgo, M. Rosa leg., without date, 2 ma ( MNRJ); Santa Maria Madalena (Parque Estadual do Desengano, Ribeirão Vermelho), Exp. Aracnologia´98 leg., 23– 25.iii.1998, 2 fe & 1 im ( MNRJ 5717).

Diagnosis: E. pusillus resembles E. incus , E. nigrimaculatus , E. acrophthalmus , E. alpinus , E. didactylus and E. geometricus because of the cylindrical prolateral median process on the male trochanter IV, and can be distinguished by: The ocularium with 2 spines; irregular projection on the retrolateral margin of the prolateral apical apophysis of coxa IV and the shape of cylindrical prolateral median process of male trochanter IV: Apically blunt and basally with a small, blunt, slightly conical apophysis. Unlike E. alpinus +, the penis of E. pusillus has a ventral process of the glans.

Redescription: Male (MZSP 1736): Dorsum ( Fig. 29A,B): Measurements: SL 4.00; SMW 3.70; femur I 1.80; II 3.70; III 2.20; IV 3.50. Median paracheliceral projection of similar-size as PAM. Ocularium far from anterior scutal margin; with 2 spines and 13 tubercles. Carapace with 30 scattered tubercles. Scutal area I with 29–30 scattered tubercles on each side; II with 58; III with 54 and a median spine of medium size, slightly oblique, abruptly curved subapically, not surpassing groove V; IV with 40 tubercles. Posterior margin of dorsal scutum and free tergites I–III with a row of 12, 15, 12, 10 tubercles, respectively. Anal operculum with 31 tubercles.

Venter: Coxa I with 16–21 tubercles, median and distal ones largest; II with 28–35, distal ones largest; III– IV irregularly tuberculate.

Chelicera: Segment I with 2 tubercles.

Pedipalpus: Trochanter dorsally inflated, smooth. Femur dorsally with 3 aligned tubercles; ventrally with 1 large basal tubercle, 1 small one. Tibial setation: Prolateral iii, retrolateral IiIi/IIi. Tarsal setation: Prolateral iIi, retrolateral IiIi.

Legs ( Fig. 29C–J): Coxa II with 1 tubercle on retrolateral margin; IV densely tuberculate, with 1 oblique prolateral apical apophysis, this conical, long, blunt, curved posteriad and slightly ventrad, with irregular projections on retrolateral margin. Trochanters I–IV with scattered tubercles; IV prolaterally with 1 cylindrical and flattened median process, this apically blunt; basally with a small, blunt, slightly conical apophysis; retrolaterally with 1 large pointed median tubercle, 1 large apical tubercle. Femur I with small PDS, RDS; ventrally with 2 rows of slightly enlarged tubercles; II–IV with medium PDS, RDS; III sinuous, ventrally with 2 rows of moderately enlarged tubercles, increasing in size distally, prolateral ones enlarged; IV sinuous, ventrally with 2 rows of tubercles, prolateral ones enlarged, increasing in size distally, 1 PVS; 1 retrolateral apical spine. Tibia III ventrally with 2 rows of tubercles increasing in size subapically, becoming high, pointed; IV with 2 ventro-apical spines. Metatarsus IV with tubercles decreasing in size and amount distally. Tarsal segmentation: 6, 10–11, 6, 6.

Penis ( Fig. 42C,D): Stylus with medio-ventral trichomes, apex slightly flattened; with angular medioventral projection. Ventral process of glans curved, apex blunt, slightly swollen. Ventral plate with concave sides; with 3 pairs of curved distal setae; 1 pair of short, straight, blunt, median setae; 4 pairs of straight basal setae.

Coloration: Brown; anterior part of coxa IV dark brown on background, with light brown spots; light brown on tarsi. Dark brown on legs I–III, on leg IV from prolateral apical apophysis of coxa IV to distal part of metatarsus.

Female (allotype of E. vervloeti ; MZSP 286): Dorsum: Measurements: SL 4.05; SMW 3.50; femur I 1.85; II 3.60; III 2.65; IV 3.45. Posterior margin of dorsal scutum with 11 scattered tubercles, 1 row of 22. Free tergite I with 7 scattered tubercles, 1 row of 23; II with 9 scattered, 1 row of 22; III with 30 scattered. Legs: Coxa IV densely tuberculate, with 1 oblique prolateral apical apophysis, this conical, short, blunt, curved backwards. Trochanters I–IV with scattered tubercles; I–II with 1 large ventro-basal tubercle; III with enlarged retrolateral tubercles; IV retrolaterally with 1 median, 1 large apical tubercle. Femur II ventrally with 2 rows of slightly enlarged tubercles; III ventrally with 2 rows of large tubercles, increasing in size distally, prolateral ones enlarged, 1 large prolateral apical tubercle; IV ventrally with 2 rows of tubercles, prolateral ones increasing in size distally, 1 large prolateral apical tubercle. Tibiae I, III ventrally with 2 rows of slightly enlarged tubercles. Tarsal segmentation: 6, 9, 6, 6. Coloration: Brown; light brown on metatarsi and tarsi I and IV, on tibia and tarsi II, apex of tibia, metatarsi and tarsi III. Dark brown on anterior margin of dorsal scutum, coxae I–IV, trochanter IV and patellae III–IV.

Variation in males (n=6): Measurements: SL 4.00–4.10; SMW 3.60–3.80; femur I 1.80–2.00; II 3.70– 4.00; III 2.20–3.00; IV 3.50–3.70. Pedipalpus: Femur with 1–2 prolateral subapical setae. Tibial setation: Prolateral IIi/iii, retrolateral IiIi/IIi/II. Tarsal setation: Prolateral iIi/Ii. Femur I with reduced or small PDS, RDS; II with reduced to medium PDS; III with small or medium PDS. Tarsal segmentation: 6, 8–11, 6, 6. Some beta males show the prolateral median process of trochanter IV developed as a conical, slightly flattened structure.

Variation in females (n=6): Measurements: SL 3.60–4.20; SMW 3.20–3.60; femur I 1.60–1.90; II 3.20– 3.60; III 2.40–2.70; IV 3.00–3.45. Pedipalpus: Tibial setation: Prolateral IiIi/IIi/iii, retrolateral IiIi/IIi/Ii. Tarsal setation: Retrolateral IiIi/Iiii. Tarsal segmentation: 6, 8–10, 6, 6.

Taxonomical notes: We could relate E. pusillus with E. vervloeti on the basis of pictures of syntypes kindly sent by Prof. Dr. Nicolaj Scharff, curator at the Zoologisk Museum Universitet, København, and by Dr. J.P.L. Guadanucci, professor at Universidade Federal do Vale do Jequitinhonha e Mucuri, Diamantina. We conclude that these are, in fact, the same species, because of similarities in the ocularium, apical spines of femora, density of tubercles on the dorsal scutum, shape, size and inclination of the median spine in area III and body size. The original description by Sørensen refers to two prolateral subapical setae on the femur of the pedipalpus, which led to the creation of a new genus ( Eusarcoides Roewer 1913 ). However, this characteristic, which occurs in only one of the syntypes, is a rare morphological variation that can be found also in other specimens of the population, and is not restricted to E. pusillus . The new synonymy is proposed although females of some species are similar to each other and difficult to identify with certainty. In others, such as E. alpinus , E. didactylus , E. geometricus , E. nigrimaculatus and E. catharinensis , females can be clearly distinguished from each other.

Type localities: Brazil. Of E. pusillus : Rio de Janeiro. Of E. vervloeti : Espírito Santo, Santa Leopoldina, Chaves.

Geographical distribution ( Fig. 50B): Brazil. S Bahia to Rio de Janeiro States .