Arnapa meja Huber, 2019

Huber, Bernhard A. & Carvalho, Leonardo S., 2019, Filling the gaps: descriptions of unnamed species included in the latest molecular phylogeny of Pholcidae (Araneae), Zootaxa 4546 (1), pp. 1-96 : 21

Arnapa meja Huber sp. n.

Figs 55–59 , 72 , 81–83

Gen.n. Ind107: Eberle et al. 2018 (molecular data); Huber et al. 2018: fig. 2.

Type material. INDONESIA: ♂ holotype, ZFMK (Ar 20609), West Papua, Manokwari, Gunung Meja (0.860°S, 134.084°E), 190 m a.s.l., 8.xi.2009 (S. Sutono) .

Other material examined. INDONESIA: 6♀, ZFMK (Ar 20610), and 1♂ 1♀ in pure ethanol, ZFMK (Ind201), same data as holotype .

Etymology. The species name is derived from the type locality; noun in apposition.

Diagnosis. Distinguished from known congeners by armature of male chelicerae ( Fig. 58 ; single lateral row of small apophyses), by presence of whitish projection at basis of bulbal process ( Fig. 59 ), by procursus with strong distal sclerite ( Figs 56–57 ), by presence of large brown plate in front of epigynum ( Fig. 81 ), and by large pore plates bordered anteriorly by large sclerites ( Figs 72 , 83 ).

Description. Male (holotype). MEASUREMENTS. Total length 2.2, carapace width 1.0. Distance PME-PME 100 µm; diameter PME 90 µm; distance PME-ALE 70 µm; distance AME-AME 20 µm, diameter AME 40 µm. Leg 1: 32.9 (7.7 + 0.4 + 8.0 + 14.2 + 2.6), tibia 2 missing, tibia 3: 3.2, tibia 4: 4.6; tibia 1 L/d: 100.

COLOR (in ethanol). Carapace ochre-yellow with wide dark brown bands laterally at margin and medially including large part of ocular area; clypeus with pair of dark bands between eye triads and rim; sternum ochreyellow; legs light brown, without dark rings, tips of femora and tibiae whitish. Abdomen gray, dorsally densely covered with dark marks, ventrally with indistinct light brown mark in front of gonopore, dark median band behind gonopore, light brown area and pair of large dark ventro-lateral marks in front of spinnerets.

BODY. Habitus as in close relatives (cf. Figs 39, 41, 43 ). Ocular area elevated, thoracic furrow present; clypeus unmodified. Sternum wider than long (0.64/0.46), unmodified.

CHELICERAE. As in Fig. 58 , with 10–11 apophyses laterally on each side; without modified hairs; with stridulatory ridges.

PALPS. As in Figs 55–56 ; coxa unmodified, trochanter with low rounded process ventrally, femur strongly widened (similar only in A. arfak ), with rounded retrolateral process proximally, with prolateral stridulatory pick (modified hair) proximally, patella ventrally reduced (not closed), tarsus small, procursus with dorsal process proximally, ventral side concave but without distinct pocket, distally with strong retrolateral apophysis and prolateral membranous structures ( Fig. 57 ); genital bulb large, with short membranous projection at base of complex process ( Fig. 59 ).

LEGS. Without spines; few vertical hairs; with curved hairs on all legs (tibiae and metatarsi, few on femora); retrolateral trichobothrium of tibia 1 at 7%; prolateral trichobothrium present on all tibiae; tarsus 1 with ~35 pseudosegments, distally distinct.

Male (variation). No variation seen. Legs 1 missing in other male examined.

Female. In general similar to male but sternum medially brown. Tibia 1 in 6 females: 5.6–6.7 (mean 6.3). Epigynum anterior plate divided into three sections ( Fig. 81 ): anterior bulging brown area, central membranous part with transversal folds, and posterior part brown laterally and whitish medially; posterior plate very short and wide. Internal genitalia with large pore plates bordered anteriorly by massive sclerites ( Figs 72 , 83 ).

Distribution. Known from type locality only ( Fig. 343 ).

Natural history. This species occupied the same microhabitat as the syntopic Arnapa manokwari (see above). The two species appeared indistinguishable in the field.

Figures

FIGURE 343. Known distribution of Arnapa gen. n.; red marks: undescribed species. Further undescribed species that might belong in this genus are known from the Caroline Islands and from Papua New Guinea east to the Louisiade Archipelago.

FIGURES 55–59. Arnapa meja sp. n. (ZFMK, Ar 20609). 55–56. Left male palp, prolateral and retrolateral views. 57. Left procursus, dorsal view. 58. Male chelicerae, frontal view. 59. Left genital bulb, dorsal view; arrow points at distinctive whitish projection at basis of bulbal process. Scale lines: 0.3 (58), 0.5 (55–57, 59).

FIGURES 70–74. Arnapa spp., cleared female genitalia, dorsal views. 70. A. arfak sp. n. (ZFMK, Ar 20605). 71. A. manokwari sp. n. (ZFMK, Ar 20608). 72. A. meja sp. n. (ZFMK, Ar 20610). 73. A. tolire sp. n. (ZFMK, Ar 20613). 74. A. tinoor sp. n. (ZFMK, Ar 20616). Scale lines: 0.3.

FIGURES 81–89. Arnapa spp., epigyna, ventral views, and cleared female genitalia, ventral and dorsal views. 81–83. A. meja sp. n. (ZFMK, Ar 20610). 84–86. A. tolire sp. n. (ZFMK, Ar 20613). 87–89. A. tinoor sp. n. (ZFMK, Ar 20616). Scale lines: 0.5.

FIGURES 39–44. Arnapa spp., live specimens. 39–40. A. arfak sp. n., male and female from Mokwam. 41–42. A. tolire sp. n., male and female with egg sac from Ternate. 43–44. A. tinoor sp. n., male and female from near Tomohon.