Megalopsalis Roewer, 1923

Taylor, Christopher K., 2013, Further revision of the genus Megalopsalis (Opiliones, Neopilionidae), with the description of seven new species, ZooKeys 328, pp. 59-117 : 62-64

Megalopsalis Roewer, 1923

Macropsalis Sørensen, 1886: 54-55 non Sclater 1866 - Pocock 1903: 398; Hogg 1910: 277; Roewer 1911: 102, 1912: 278.

Megalopsalis Roewer, 1923: 866 (replacement name for Macropsalis Sørensen) - Forster 1944: 184-185 (referring to material of Forsteropsalis Taylor, 2011); Crawford 1992: 28, 29; Taylor 2011: 31.

Spinicrus Forster, 1949: 63 syn. n.; Hickman 1957: 73; Crawford 1992: 43.

Hypomegalopsalis Taylor, 2011: 45 syn. n.

Type species.

Macropsalis serritarsus Sørensen, 1886 by monotypy.

Other included species.

Megalopsalis serritarsus -species group: Megalopsalis epizephyros Taylor, 2011, Megalopsalis eremiotis Taylor, 2011, Megalopsalis hoggi Pocock, 1903, Megalopsalis pilliga Taylor, 2011.

Megalopsalis leptekes -species group: Megalopsalis leptekes , 2011, Megalopsalis tanisphyros (Taylor, 2011), comb. n. (= Hypomegalopsalis tanisphyros ).

Megalopsalis minima -species group: Megalopsalis minima (Kauri, 1954), comb. n. (= Spinicrus minimum ), Megalopsalis porongorupensis (Kauri, 1954), comb. n. (= Spinicrus porongorupense ), Megalopsalis suffugiens sp. n., Megalopsalis walpolensis sp. n..

Species not placed in species groups: Megalopsalis atrocidiana sp. n., Megalopsalis caeruleomontium sp. n., Megalopsalis coronata sp. n., Megalopsalis puerilis sp. n., Megalopsalis stewarti (Forster, 1949), comb. n. (= Spinicrus stewarti ), Megalopsalis sublucens sp. n., Megalopsalis tasmanica (Hogg, 1910), comb. n. (= Pantopsalis tasmanica ), Megalopsalis thryptica (Hickman, 1957), comb. n. (= Spinicrus thrypticum ).

Diagnosis.

Megalopsalis can be distinguished from all other genera of Enantiobuninae by its male genital morphology, with the glans being relatively short, broad, distally flattened, and more or less subtriangular in ventral view (e.g. Fig. 3d). It can be further distinguished from Monoscutum , Acihasta , Templar and Australiscutum by having the legs relatively long and thin, and the dorsum of the opisthosoma weakly sclerotised and unarmed (except Megalopsalis atrocidiana ; Forster 1948; Taylor 2008a, 2009). Pantopsalis , Forsteropsalis , Neopantopsalis and Mangatangi differ from all Megalopsalis species except Megalopsalis caeruleomontium by the presence of setae on the mobile finger of the chelicera ( Taylor 2013: figs 1d, 2c). Tercentenarium has males with a distinct frontodistal bulge on the chelicerae ( Taylor 2008b: fig. 3), and females with a ‘keyhole’ -like emargination at the front of the genital operculum ( Taylor 2008b: fig. 10).

Description.

Ozopores usually large, oblong (small, round in Megalopsalis nigricans ). Dorsum of opisthosoma unarmed (except with transverse rows of spines in Megalopsalis atrocidiana ). Chelicera segment II denticulate or not; mobile finger usually closing tightly against finger of segment II, fingers bowed apart in larger males of Megalopsalis caeruleomontium . Pedipalp usually with patella shorter than tibia (slightly longer in Megalopsalis nigricans ); apophysis present or absent on patella; claw with ventral tooth-row. Glans relatively short, broad, more or less subtriangular in ventral view, proximal section usually somewhat inflated dorsally (except in Megalopsalis nigricans ); distal section more or less dorsoventrally flattened. Spiracle with reticulate or partially reticulate covering spines (reduced or absent in Megalopsalis minima -species group); lace tubercles present or absent.

Distribution

(Figs 1, 7). Southern and eastern Australia.

Comments.

The genus Spinicrus as previously defined ( Forster 1949) is likely to be non-monophyletic with regard to both Megalopsalis and Hypomegalopsalis , and lacks clear synapomorphies (see phylogenetic analysis below). In contrast, the clade uniting these three genera is characterised by a distinct penis morphology, and they are hence united into a single genus Megalopsalis . The species groups listed above are clades that were consistently recovered in the phylogenetic analysis under varying analytical conditions; those species not placed in groups did not form consistent subgeneric clades across all analyses. Members of the Megalopsalis serritarsus - and Megalopsalis leptekes -groups were described by Taylor (2011).

Megalopsalis tasmanica and Megalopsalis thryptica were described in detail by Hickman (1957), and so are not redescribed here. Both sexes of Megalopsalis tasmanica can be distinguished from other Neopilionidae by their distinctive elongate opisthosoma as illustrated by Hickman (1957: fig. 29); this distinction is even more pronounced in the female. See below under Megalopsalis stewarti for discussion of the distinction between this species and Megalopsalis thryptica .

Key to males of species of Megalopsalis