Diplocentrus izabal Armas & Trujillo, 2016

de Armas, Luis F. & Trujillo, Rony E., 2016, A new species of Diplocentrus (Scorpionidae: Diplocentrinae) from western Izabal, Guatemala, Euscorpius 225, pp. 1-8 : 1-7

Diplocentrus izabal Armas & Trujillo , sp. n.

( Figures 1–9, 12–23, Table 1) http://www.zoobank.org/ urn:lsid:zoobank.org:act:3AF93098-C898-4C2E-9C97-841559F78304

HOLOTYPE. ♂ ( MHN), 7 km east of Taquincó (15.53100' N, -89.60481' W; 348 m a.s.l.), El Estor Municipality, Izabal Department, Guatemala, 19-12- 2010, leg. C. Vásquez Almazán. Note: Left legs I-III are detached.

PARATYPES: 1♀ (IESC-3.3765), 1♀ ( MHN), same data as the holotype .

DISTRIBUTION. Only known from the type locality ( Fig. 1).

ETYMOLOGY. The specific name is a noun in apposition, taken from the department to which belongs the type locality.

DIAGNOSIS. The following combination of characters is diagnostic for D. izabal , n. sp. Total length 50– 54 mm. Base coloration (adult), brown. Carapace anteromedian notch shallow, V-shaped ( Figs. 2, 18). Pedipalp femur with dorsal surface finely and sparsely granular on the basal one-half (♂, Fig. 12) or medially (♀, Fig. 18). Pedipalp patella, with intercarinal surfaces faintly reticulate (♂, Fig. 13) or smooth (♀, Fig. 21); dorsointernal carina strong (♂; Fig. 13) or weak (♀), smooth; dorsoexternal carina moderately (♂, Fig. 13) or weakly (♀) developed, smooth. Pedipalp chela manus with dorsal surface markedly (♂; Fig. 14) or feebly (♀; Fig. 22) reticulate; digital carina strongly developed (♂, Fig. 14) or weakly developed (♀), smooth; ventral median carina strong, faintly crenulate (♂, Fig. 15) or weakly developed, smooth (♀). Legs I–IV tarsomere II, counts of spiniform macrosetae in pro- and retroventral rows: 4/4-5: 4-5/4-5: 5/5: 5/5. Pectinal tooth count, 11 (♀, ♂).

Diplocentrus izabal , n. sp., resembles D. lachua Armas, Trujillo & Agreda, 2011 , and Diplocentrus maya Francke, 1977 in adult size and tarsomere II counts of ventral spiniform macrosetae, but they may be distinguished as follows. The carapace anteromedian notch is V-shaped in D. izabal , but U-shaped in D. lachua and D. maya . Males of D. maya have a more globose telson ( Fig. 10), pectines with 12–15 teeth, metasoma without reticulations, carapace more granular, pedipalp manus more attenuate (ratio length/width = 2.4–2.5 vs 1.6 in D. izabal ). Male of D. lachua also resembles that of D. izabal by having reticulate both metasoma segments and pedipalp patella, as well as attenuate telson ( Fig. 11), but it has a darker coloration, carapace finely granular through, pectines with 13 teeth, and carapace as long as the pedipalp manus (in D. izabal , carapace is 1.2 times longer than pedipalp manus).

DESCRIPTION (adult male holotype; Figs. 2–8, 12–17). Carapace reddish-brown, uniformly variegated with dark fine reticulations. Coxosternal region pale brown. Pedipalps dark reddish-brown, carinae darker. Legs pale brown. Tergites brown, densely infuscate; sternites pale brown. Metasoma and telson reddishbrown; carinae moderately infuscate.

Carapace mostly smooth, with very fine granules on lateral areas and interocular triangle; anterior margin moderately setose, subgranulose; anteromedian notch shallow, V-shaped; anteromedian furrow wide, deep; three pairs of subequal lateral ocelli.

Pectines with 11/11 teeth.

Pretergites smooth. Tergites fine and faintly granular, shagreened; VII with dorsosubmedian and dorsolateral carinae weakly developed, granulose. Sternites smooth; VII with poorly developed lateral carinae, smooth.

Metasomal segments with dorsal intercarinal surfaces weakly reticulate on I–IV, smooth on V; lateral intercarinal surfaces reticulate; ventral intercarinal surfaces smooth. Segments I–IV with dorsal lateral and lateral supramedian carinae moderately developed, granular; lateral inframedian carinae weakly developed, slightly granular to crenulate on I, weakly developed to obsolete on II–IV, smooth; ventral lateral carinae weakly developed, smooth on I–II, weakly granular to crenate on III–IV; ventral submedian carinae obsolete on I–IV. Segment V length/pedipalp femur length ratio = 1.09; dorsal lateral carinae moderately developed, granular; lateral inframedian carinae weakly developed, smooth; ventral lateral carinae moderately developed, granular, with subspiniform granules; ventral median carina moderately developed, granular, with subspiniform granules posteriorly; ventral transverse carina moderately developed, comprising six subspiniform granules. Telson moderately attenuate (length/width ratio = 2.02); vesicle with lateral surfaces smooth and ventral surface granular anteriorly; subaculear tubercle stout, subconical. Measurements ( Table 1).

Pedipalps orthobothriotaxic, type C. Femur ( Fig. 12) 1.4 times wider than height; dorsal intercarinal surface shallowly convex, finely and sparsely granular in its proximal one-half; external intercarinal surface smooth; ventral intercarinal surface flat, smooth; internal intercarinal surface coarsely and densely granular; dorsointernal carina strongly developed, granular; dorsoexternal carina weakly developed, granular proximally and smooth distally; ventroexternal carina obsolete; ventrointernal carina moderately developed, granular proximally, becoming obsolete distally. Patella ( Fig. 13) with dorsal, external and ventral intercarinal surfaces slightly reticulate; internal intercarinal surface finely granulose; proximal tubercle moderately developed; dorsointernal carina strongly developed, smooth; dorsoposterior carina weakly developed, smooth; externo- median weakly developed, smooth; ventroexternal carina moderately developed in its proximal two-third, smooth, but obsolete in the distal one-third; ventrointernal carina moderately developed, comprising 5–6 conical granules in its proximal one-half. Chela ( Figs. 14–17): manus slender, 1.7 as height as width, sparsely setose; dorsal and external intercarinal surfaces strongly reticulate; dorsal marginal carina moderately developed, coarsely granular; digital carina strongly developed, smooth; dorsal secondary and external secondary carinae moderately developed, smooth; ventroexternal carina weakly developed, smooth; ventromedian carina strongly developed, faintly crenulate, directed towards midpoint of movable finger articulation; internodorsal and internomedian carinae weakly developed, smooth, but having obsolete fine granules; internoventral carinae weakly developed, smooth.

Legs I–IV polished. Tarsomere II counts of spiniform macrosetae in pro- and retroventral rows: 4/4 4/4: - /- -/-: 5/5 5/5: 5/5 5/5 (tarsomere II is lacking in legs II).

FEMALE ( Figs. 9, 18–23). Adult females mainly differ from male holotype by having carapace and tergites smooth, shiny; pedipalps shorter, with patellae not reticulate, and chela faintly reticulate; pectinal teeth shorter; metasomal with intercarinal spaces not reticulated and segments stouter; telson most globose; genital operculum elliptical. Both paratype females have 11/11 pectinal teeth. Measurements ( Table 1).

VARIATION. Female paratypes have the following tarsomere II counts of ventral spiniform macrosetae on legs I-II: 4/5 4/4: 4/5 4/5 ( IESC), and 4/4 -/-: 5/4 4/4 ( MHN). Total length of the smaller paratype was 50.0 mm .

NATURAL HISTORY. The type series of D. izabal was collected in a subtropical wet forest, 348 m a.s.l., about 3.5 km East from Cahabón river, near the border with Panzós, Alta Verapaz department. Some indicator species from this forest are Attalea cohune , Terminalia amazonia , Brosimun alicastrum , Lonchocarpus spp ., Virola spp ., Cecropia peltata , Ceiba pentandra and Vochysia guatemalensis ( Cruz, 1982) . According to Méndez (2008), the site is located at the Biogeographic Region II, corresponding to the northwest-northeast intermediate and highlands, which includes the mountain systems of Lacandón, Chamá, Santa Cruz and part of the Maya Mountains. This biogeographic unit supports high levels of endemism and stands out as the most diverse Guatemalan region for mammals, birds, reptiles and amphibians.