Arnapa manokwari 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 : 19-21

Arnapa manokwari Huber sp. n.

Figs 50–54 , 71 , 78–80

Type material. INDONESIA: ♂ holotype, ZFMK (Ar 20607), 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: 2♂ 1♀ abdomen, ZFMK (Ar 20608), and 1♀ prosoma (abdomen in Ar 20608) in pure ethanol, ZFMK (Ind200), same data as holotype .

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

Diagnosis. Distinguished from known congeners by shape of bulbal process ( Fig. 54 ; with three distinctive branches), by presence of small conical process on genital bulb ( Fig. 51 ), by procursus tip with pair of slender prolateral processes ( Fig. 52 ), and by female internal genitalia ( Figs 71 , 79–80 ; with pair of sclerotized internal pockets; similar only in A. arfak ); from most congeners also by armature of male chelicerae ( Fig. 53 ; two distinctive distal apophyses on each side directed towards median; similar only in A. arfak ).

Description. Male (holotype). MEASUREMENTS. Total length 2.1, carapace width 0.95. Distance PME-PME 90 µm; diameter PME 80 µm; distance PME-ALE 70 µm; distance AME-AME 15 µm, diameter AME 45 µm. Leg 1: 31.5 (7.2 + 0.4 + 7.4 + 14.2 + 2.3), tibia 2: 4.0, tibia 3: 2.8, tibia 4: 4.1; tibia 1 L/d: 93.

COLOR (in ethanol). Carapace ochre-yellow with wide dark brown bands laterally at margin and medially including posterior part of ocular area; clypeus with pair of dark bands between eye triads and rim; sternum ochreyellow; legs light brown, without darker 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 (0.56/0.40), unmodified.

CHELICERAE. As in Fig. 53 , with pair of distal apophyses directed towards median as in A. arfak but other apophyses in distinctive arrangement; without modified hairs; with stridulatory ridges.

PALPS. As in Figs 50–51 ; coxa unmodified, trochanter with short ventral apophysis directed towards distal (similar A. arfak ), femur widened (much less than in A. arfak ), with large rounded retrolateral process proximally, with prolateral stridulatory pick (modified hair) proximally, patella ventrally reduced (not closed), tarsus small, procursus with flat dorsal process proximally with small scales, without ventral pocket, distally with distinctive sclerotized and membranous elements ( Fig. 52 ); genital bulb large, with conical dorsal projection and complex process ( Fig. 54 ).

LEGS. Without spines, few vertical hairs; with curved hairs on tibiae and metatarsi 1–2; retrolateral trichobothrium of tibia 1 at 8%; prolateral trichobothrium present on all tibiae; tarsus 1 with ~35 pseudosegments, distally distinct.

Male (variation). Number and size of sclerotized cones on chelicerae slightly variable but pattern consistent. Tibia 1 in 2 other males 6.7, 7.7.

Female. In general similar to male. Tibia 1 in 1 female: 4.4. Epigynum anterior plate trapezoidal ( Fig. 78 ), posterior plate large, with transversal ridges. Internal genitalia with pair of internal pockets visible through cuticle, with large lateral membranous folds, narrow anterior ‘valve’, and pair of pore plates close together ( Figs 71 , 79– 80 ).

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

Natural history. This species was found in small holes in the ground, in domed webs with a diameter of about 15 cm. When disturbed, the spiders usually ran away towards the back of the hole, but sometimes vibrated in their webs.

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 50–54. Arnapa manokwari sp. n. (ZFMK, Ar 20608). 50–51. Left male palp, prolateral and retrolateral views; arrow points at distinctive conical process on genital bulb. 52. Left procursus, dorsal view. 53. Male chelicerae, frontal view. 54. Left genital bulb, dorsal view. Scale lines: 0.3 (53), 0.5 (50–52, 54).

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 75–80. Arnapa spp., epigyna, ventral views, and cleared female genitalia, ventral and dorsal views; arrows point at internal putative pockets. 75–77. A. arfak sp. n. (ZFMK, Ar 20605). 78–80. A. manokwari sp. n. (ZFMK, Ar 20608). 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.