Pholcophora mazatlan Huber sp. nov.

urn:lsid:zoobank.org:act: C787210E-FE17-42BD-AF00-7C5364558495

Figs 3B–E, 9–13, 33C–D

Diagnosis

Distinguished from similar congeners ( P. papanoa sp. nov., P. mexcala, P. americana) by shape of male cheliceral apophyses (Fig. 10A–B; very long, directed upwards, without proximal humps) and by shape of male bulbal process (Fig. 10F–H; small dorsal process in very distal position; distinctive semi-transparent ventral flap). From very similar P. papanoa also by main element of procursus more gradually narrowing distally (Fig. 10E), by male cheliceral apophyses more strongly directed upwards, and by thinner male leg femora (0.18–0.20 vs 0.28–0.30). From P. americana also by tip of procursus (semi-transparent process not widening distally) and by shape of epigynum (Fig. 11A, C; main epigynal plate posteriorly straight).

Etymology

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

Type material

Holotype MEXICO – Guerrero • ♂; ~ 2 km N of Mazatlán; 17.4567° N, 99.4740° W; 1300 m a.s.l.; 3 Oct. 2019; B.A. Huber and A. Valdez-Mondragón leg.; LATLAX.

Paratypes MEXICO – Guerrero • 1 ♀; same collection data as for holotype; ZFMK Ar 23943 • 1 ♂, 11 ♀♀; same collection data as for holotype; LATLAX .

Other material examined

MEXICO – Guerrero • 3 ♀♀, in pure ethanol; same collection data as for holotype; one female used for SEM; ZFMK Mex209 • 3 ♀♀ abdomens, together with female paratype; same collection data as for holotype; prosomata used for molecular work; ZFMK Ar 23943 .

Description

Male (holotype)

MEASUREMENTS. Total body length 1.90, carapace width 0.80. Distance PME-PME 70 µm; diameter PME 60 µm; distance PME-ALE 30 µm; distance AME-AME 20 µm; diameter AME 30 µm. Leg 1: 4.55 (1.30 + 0.30 + 1.15 + 1.30 + 0.50), tibia 2: 1.00, tibia 3: 0.85, tibia 4: 1.25; tibia 1 L/d: 12; diameters of leg femora 0.18–0.20, of leg tibiae 0.10.

COLOUR (in ethanol). Prosoma and legs ochre-yellow, carapace with indistinct Y-mark, legs without darker rings; abdomen grey with dark bluish internal marks; ventrally with ochre plate in front of gonopore.

BODY (Fig. 3B–C). Ocular area barely raised. Carapace with distinct but shallow thoracic groove (cf. Fig. 13A). Clypeus unmodified, very short (clypeus rim to ALE: 0.22). Sternum slightly wider than long (0.56/0.46), oval (not narrow posteriorly), with pair of distinct anterior processes (~0.1 long) near coxae 1. Abdomen globular.

CHELICERAE (Fig. 10A–B). With pair of long frontal apophyses; stridulatory files very fine, poorly visible in dissecting microscope; distances between cheliceral stridulatory ridges proximally 2.4 µm, distally 3.5 µm.

PALPS (Fig. 9). Coxa unmodified; trochanter without process; femur proximally with retrolateral-ventral process and prolateral stridulatory pick, distally widened but simple, slightly curved towards dorsal; femur-patella joints slightly shifted toward prolateral side; tibia globular, with two trichobothria; tibia-tarsus joints not shifted to one side; procursus very simple (Fig. 10C–E), narrow distal part slightly bent towards prolateral, with semi-transparent tip; genital bulb with small dorsal process in very distal position, distally with distinctive semi-transparent ventral flap (Fig. 10F–H).

LEGS. Without spines and curved hairs; with vertical hairs in two narrow dorsal bands proximally on tibiae 1 and 2 (length ~30 µm; length of dorsal trichobothrium on tibia 1: ~90 µm); retrolateral trichobothrium of tibia 1 at 64%; prolateral trichobothrium absent on tibia 1; tarsus 1 with ~7 pseudosegments, only distally 2–3 distinct.

Variation (male)

Tibia 1 in second male: 1.30.

Female

In general, similar to male (Fig. 3D–E) but sternum without pair of anterior humps, tibiae without higher than usual density of short vertical hairs, and chelicerae without stridulatory files. Tibia 1 in 11 females: 1.00–1.20 (mean 1.08). Epigynum (Figs 11, 13B) with simple anterior plate protruding in lateral view; posterior plate wide, median part separated anteriorly from lateral parts by pair of whitish areas. Internal genitalia (Fig. 12) very simple, apparently without or with small and indistinct median receptacle, without or with very small pore plates.

Distribution

Known from type locality only, in Mexico, Guerrero (Fig. 2).

Natural history

The spiders were found by turning rocks in a forested valley (Fig. 34A). They shared the microhabitat with at least four further species of Pholcidae (Modisiminae): two representatives of Modisimus Simon, 1893, one Psilochorus Simon, 1893, and one species of uncertain generic position.