Chrysometa xamaticpac, Salgueiro-Sepúlveda & Álvarez-Padilla, 2018

Salgueiro-Sepúlveda, F. Javier & Álvarez-Padilla, Fernando, 2018, New species of the orb-weaving spider genus Chrysometa (Araneae, Tetragnathidae) from oak forests near of the Pico de Orizaba National Park (Veracruz, Mexico), Zootaxa 4450 (3), pp. 301-330 : 314-316

Chrysometa xamaticpac new species

Figures 9 , 10 , 19

Type material. Holotype ( CNAN-T1187 ). Female from Pico de Orizaba National Park , Xamaticpac, Calcahualco, Veracruz, Mexico. Plot II: 19° 7' 32.5" N, 97° 4' 3.2" W, 1,700 m . April 19–27, 2013. Allotype ( CNAN-T1188 ). Male from same locality. Paratypes. Four females and nine males. Types are deposited in the Colección Nacional de Arácnidos ( CNAN) at the Instituto de Biología ( IBUNAM).

Etymology. The species epithet is a noun in apposition and refers to the type locality.

Diagnosis. Females of C. xamaticpac can be distinguished from all sympatric species by the following features: epigynum transverse bar very short with small and thin arms and protruding over the septum ( Figs. 9D , 10D ). Males of C. xamaticpac are distinguished by the following features: large and thin embolus, Ç-shaped paracymbium in ventral view with a very short lower prong with a square tip ( Figs. 9I , 10A, B, C ).

Description. Female. Total length 4. Cephalothorax: length 2, width 1.5. Carapace pale-yellow, dark-yellow pattern over the cephalic region narrowing towards the fovea ( Fig. 9A ). Ocular area pale-yellow. Eyes subequal in size ( Fig. 9G ). AME diameter 0.1, PME 0.14, ALE and PLE 0.14. Chelicerae yellow, with few scattered setae ( Fig. 9G ). Endites longer than wide, yellow, internal margins pale-yellow. Labium wider than long, dark brown, paleyellow on the posterior part. Sternum dark-yellow, wider between the first and second legs ( Fig. 9C ). Abdomen: pale-brown, dorsally covered with small guanine silvery patches, with four transversal black lines ( Fig. 9A, B ); ventrally dark-yellow, with two lines of guanine patches forming a central brown rectangle between the spinnerets and the epigynum, one yellow spot on each side of spinnerets ( Fig. 9C ). Leg lengths: I 12, II 6.9, III 4 and IV 5.8. Legs pale-yellow, the first segments yellow, darker on joints, with ventral and dorsal black spots. Tarsi dark-brown. Epigynum: epigynal plate trapezoidal, wider than long; transverse bar very short, without arms and protruding over the septum. Septum with thick margins and well sclerotized. Copulatory openings small, not sclerotized ( Figs. 9D , 10D ). Spermathecae, copulatory ducts and fertilization ducts as shown in Figure 9E, F .

Male. As in female except as noted. Total length 3.6. Cephalothorax: length 1.9, width 1.4. Carapace: dorsal coloration darker, pattern weaker. Eyes subequal in size. AME diameter 0.08, PME 0.1, ALE and PLE 0.11. Chelicerae dark-yellow, rugose, larger and narrower, setae bases enlarged and more abundant at base; retrolateral cuticle less rugose towards the apical surfaces ( Fig. 9H ). Abdomen: dorsal and ventral coloration brighter than in female. Leg lengths: I 12, II 7.5, III 4.3 and IV 5.9. Pedipalp: CEBP triangular, curved anteriorly. CEMP small, rectangular and flattened, pointed retrolaterally. Paracymbium Ç-shaped in ventral view. Upper prong enlarged, wider than lower prong. Lower prong square and short. Embolus large and thin, tubular shape; EBA shorter than embolus and curved in apical region ( Figs. 9I , 10A, B, C ). Conductor, embolus and EBA in ventral view as in Figures 9I , 10A .

Variation. Female total length 3.8–4.5, cephalothorax length 1.6–2, cephalothorax width 1.2–1.5. Male total length 3.1–4.1, cephalothorax length 1.4–1.9, cephalothorax width 1.3–1.6. Females can vary in the pattern of the cephalic region and the dorsal surface of the abdomen. The external and internal epigynum can be more sclerotized and the transverse bar can present very short and thin arms.

Material examined. N=15. Mexico: Veracruz, Xamaticpac , Calcahualco. One female, ten males Plot II: 19° 7' 32.5" N, 97° 4' 3.2" W, 1,700 m., April 19–27, 2013. Two females Plot I: 19 7' 34.1" N, 97 4' 1.5" W, 1,710 m.; two females Plot II: 19 7' 32.5" N, 97 4' 3.2" W, 1,700 m., October 2–11, 2013. Colección Nacional de Arácnidos ( CNAN) at the Instituto de Biología ( IBUNAM) .

Distribution. Veracruz, Mexico. Known only from the type locality ( Fig. 19 ).

Biology. Specimens were collected in a Quercus forest with secondary plant growth. All specimens were found in both plots but only during the first and second expeditions (expedition I: May 21–30, 2012; expedition II: October 4–14, 2012). Most specimens were captured by direct collecting at night; only two were caught by beating vegetation.

Figures

FIGURE 9. Chrysometa xamaticpac n. sp., female. A, habitus dorsal view. B, lateral view. C, ventral view. D, epigynum ventral view. E, epigynum ventral view (cleared). F, dorsal view (cleared). G, prosoma anterior view. Male. H, prosoma anterior view. I, pedipalp ventral view. Scale bars, A, B, C, 1.0 mm; D, I, 0.2 mm; E, F, 0.1 mm; G, H, 0.5 mm.

FIGURE 10. Chrysometa xamaticpac n. sp., male. A, pedipalp ventral view, B retrolateral view. C, dorsal view. Female. D, epigynum ventral view. E, posterior view. Scale bars, 0.2 mm.

FIGURE 19. Species Distribution Map. Atotonilco Locality: Chrysometa citlaltepetl, C. triangulosa, C. rosarium, C. atotonilco and C. sagicuta.. Xamaticpac Locality: C. xamaticpac, C. puya and C. chipinque.