Forsteropsalis Taylor 2011
Creators: name: Taylor, Christopher K.
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Opiliones
Neopilionidae
Forsteropsalis

description: Forsteropsalis Taylor, 2011
Type species: Macropsalis chiltoni Hogg, 1910, by original designation.
Other included species (original combinations): Dasylobus australis Simon, 1899 (new combination), Pantopsalis distincta Forster, 1964, Megalopsalis marplesi Forster, 1944.
Description: Male with prosoma largely unarmed except scattered denticles in front of ocularium and/or at anterior corners. Medial side of pedipalpal coxa in male rectangular with blunt denticles. Pedipalp femur shorter than or subequal to length of prosoma; patella of both sexes often with small, but distinct, pointed mediodistal apophysis (absent in male of F. distincta); no densely setose area on patella; tarsal claw without tooth-row. Penis with glans medium length, subtriangular, narrowing distad in lateral view; bristle groups relatively long.
Comments: Taylor (2011) erected Forsteropsalis to include a diverse assemblage of New Zealand species previously assigned to the Australian genus Megalopsalis. Both morphological (herein) and molecular (Giribet et al. 2021b) studies have not supported Taylor’s (2011) original concept of Forsteropsalis as monophyletic (see phylogenetic discussion above for further details). Forsteropsalis is therefore restricted herein to those species most closely related to F. chiltoni. Under this restricted concept, Forsteropsalis may be distinguished from Mangatangi by the lack of a tooth-row on the pedipalpal claw and the narrower glans in lateral view, from Pantopsalis, Pakaka and Ungoliant photophaga by the lack of a mediodistal hypersetose region on the pedipalpal patella and from Pantopsalis by the presence of denticles on the pedipalpal coxa and the longer bristle groups on the penis, from Puwere and Shelob by the shorter glans appearing subtriangular in ventral view, and from the remaining species of Ungoliant by its shorter pedipalps and the absence of ventrodistal apophyses on the basal pseudosegments of distitarsus I. Forsteropsalis has a distinctly southerly range, being found in the lower half of the South Island and Stewart Island (Taylor 2011), as well as on the Auckland Islands (Forster 1964) and Chatham Islands (see below).
Forsteropsalis chiltoni and F. marplesi were only tentatively distinguished by Taylor (2011) by the number of pseudosegments in tibia II. Pseudosegment counts are a problematic character in harvestman taxonomy, having been found to vary within species and sometimes even within individuals (Suzuki 1973, 1982). However, pseudosegment count in Forsteropsalis is also correlated with overall leg length, F. marplesi tending to have longer legs than F. chiltoni (details in species key above). Molecular data have also supported the distinction between F. marplesi and F. chiltoni (Fernández et al. 2014; Giribet et al. 2021b), albeit with the suggestion that more than one species may have been confused under F. chiltoni.
Dasylobus australis was described by Simon (1899) from a female specimen collected on Chatham Island but was overlooked by all subsequent reviews of New Zealand Opiliones. Dasylobus Simon, 1878 is a western Palaearctic genus of Phalangiidae that would be extremely unlikely to occur in New Zealand, at least as part of the native fauna. I have been unable to examine the type specimen of D. australis, currently held in the Senckenberg Naturmuseum und Forschungsinstitut in Frankfurt, Germany (Porto & Pérez-González 2019). However, Simon’s (1899) description allows it to be identified as a female Forsteropsalis. A specimen of a female Forsteropsalis collected at Taiko Camp on Chatham Island, held in the collection at MONZ, confirms the presence of that genus in the Chatham group (personal observation). Unfortunately, female neopilionids cannot often be identified below genus level and no male neopilionids have been described to date from Chatham Island. The isolated location of the Chatham Islands makes it likely that any Forsteropsalis species found there will be distinct from those of the New Zealand mainland, hence I take the provisional step of recognising Dasylobus australis as Forsteropsalis australis new combination, but confirmation of its status awaits identification of male specimens.
description: Published as part of Taylor, Christopher K., 2025, Further discussion of relationships within Australasian Neopilionidae (Opiliones: Phalangioidea), with description of two new species and eight new genera, pp. 52-82 in Zootaxa 5631 (1) on page 68, DOI: 10.11646/zootaxa.5631.1.2, http://zenodo.org/record/15326621