Medionops ramirezi, Sánchez-Ruiz, Alexander & Brescovit, Antonio D., 2017

Sánchez-Ruiz, Alexander & Brescovit, Antonio D., 2017, A new genus with seven species of the Subfamily Nopinae (Araneae, Caponiidae) from the Neotropical region, Zootaxa 4291 (1), pp. 117-143 : 136-137

Medionops ramirezi new species

Figures 15–17

Types. Male holotype from Ilha Marambaia (23°4'27.1"S 43°59'7.9"W), Rio de Janeiro, Brazil, 12.xi.1992, R. Xerez, deposited in MNRJ 6370 . Paratypes: 1♂ from Praia Grande das Palmas (23°8'31.6"S 44°8'27.7"W), Ilha Grande , Rio de Janeiro, Brazil, 19–21.i.1999, M. Ramírez, Moczarski / Tullgren extrator, deposited in MACN . 1♂, 1♀ from Trindade , (23°20'31"S 44°42'52"W), 25 km. S of Paraty, Rio de Janeiro, Brazil, 23.i.1996, M. Ramírez, deposited in MACN .

Additional material examined. BRAZIL: Rio de Janeiro : Ilha Marambaia (23°4'27.1"S 43°59'7.9"W), 10– 22.xii.1992, R. Xerez, 2♂ ( MNRJ 6369 ) . Ditto, 1.x.1992, 1♂ (left palp and legs for SEM) (MNRJ 6371). Ditto, 20.i.1993, R. Xerez, 1♂ (MNRJ 6372).

Etymology. The specific name is a patronym in honor of Martin Ramírez, who collected the paratypes. Diagnosis. Males and females resemble those of M. tabay n. sp. in having the abdomen with unremarkable dorsal pattern of very fine lines, almost unnoticeable, forming four or five chevrons along a longitudinal line, but can be distinguished by having the longitudinal line short, not reaching the pedicel or the posterior part of abdomen ( Figs 17 A–B). Males with embolus length over two times the greatest diameter of the bulb ( Figs 17 D–E); females with a very wide median concavity on the distal margin of receptaculum, without septum or invagination on posterior plate ( Figs 16 G–I).

Description. Male (holotype): Total length 3.1. Carapace 1.4 long, 1.3 wide. Sternum 1.3 long, 1.2 wide. Leg measurements: I: 2.4; II: 2.3; III: 1.9; IV: 2.6. Carapace orange. Chelicerae, palps and legs light orange; coxae and trochanters lighter. Endites, labium and sternum light orange. Abdomen dark gray with unremarkable pattern of very fine closer lines, almost unnoticeable forming four or five chevrons along a short longitudinal line, not reaching the pedicel or the posterior part of abdomen ( Fig. 17 A). Anal tubercle and spinnerets lighter than abdomen. Crista extremely short, almost unnoticeable ( Fig. 15 F), gladius with the common shape among nopine ( Fig. 15 E). Palp with a spherical oval bulb, embolus longer than cymbium ( Figs 17 D–E), tip of embolus slightly curved, acuminate, with beveled opening ( Figs 16 D–F).

Female (paratype): Total length 3.4. Carapace 1.5 long, 1.4 wide. Sternum 1.4 long, 1.3 wide. Leg measurements: I: 2.4; II: 2.3; III: 2.0; IV: 2.7. Carapace, chelicerae, labium, legs, coxae, endites and sternum lighter than the male. Abdomen as in the male, but somewhat darker ( Fig. 17 B). Anal tubercle and spinnerets lighter than abdomen. Crista and gladius as in the male. External genitalia with a concave genital opening and wide sclerotization around spiracles ( Fig. 17 C). Internal genitalia with a very wide median concavity on distal margin of receptaculum (dmr); proximal margin weakly projected, internal fold (if) wide and sclerotized, wide proximal section of uterus externus (ue) ( Figs 16 G–I).

Distribution. Known only from the Brazilian coastal areas SW of Rio de Janeiro ( Fig. 21 ).

Figures

FIGURE 15. Medionops ramirezi n. sp., male (MNRJ 6371). A left leg I, prolateral oblique view. B join of tarsus and metatarsus on left leg I, prolateral oblique view. C join of tarsus and metatarsus on left leg I, prolateral view. D metatarsus on left leg II, ventral oblique view. E join of tarsus and metatarsus on left leg II, ventral oblique view. F detail of the crista, ventral oblique view. Abbreviations: ca—crista, gl—gladius.

FIGURE 16. Medionops ramirezi n. sp., A – F Male (MNRJ 6371), left palp G – I Female paratype, internal genitalia (MACN). A prolateral view. B ventral view. C tibia, prolateral view. D tip of embolus, ventral view. E tip of embolus, retrolateral view. F tip of embolus, prolateral view. G dorsal view. H posterior view. I anterior view. Abbreviations: ap—anterior plate, dmr—distal margin of receptaculum, if—internal fold, pp—posterior plate, ue—uterus externus.

FIGURE 17. Medionops ramirezi n. sp. A male holotype, habitus, dorsal view. B female paratype, habitus, dorsal view. C external genitalia of female paratype, ventral view. D left palp of male holotype, prolateral view. E left palp of male holotype, retrolateral view. Abbreviations: ap—anterior plate, ess—external sclerotization around spiracles, go—genital opening.

FIGURE 21. Map of South America showing distribution of Medionops species. Triangle, Medionops blades n. sp.; plus sign, Medionops cesari (Dupérré) n. comb.; square, Medionops claudiae n. sp.; tears, Medionops murici n. sp.; diamond, Medionops ramirezi n. sp.; circles, Medionops simla (Chickering) n. comb.; heart, Medionops tabay n. sp.