Praecantrix Hegg & Morgan-Richards & Trewick 2024, gen. nov.
Creators: name: Hegg, Danilo
name: Morgan-Richards, Mary
name: Trewick, Steven A.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Orthoptera
Rhaphidophoridae
Praecantrix

description: Genus Praecantrix gen. nov.
urn:lsid:zoobank.org:act: 38A9C3BD-9229-4AD5-9540-537D83249989
Type species
Praecantrix silvatica gen. et sp. nov.
Diagnosis
A genus of small Rhaphidophoridae (adult body length typically between 8 and 13 mm), comprising two species. The genus strongly resembles Isoplectron in its morphology, except in the terminalia. The male subgenital plate, which terminates in a single, rounded lobe at the apex in all species of Isoplectron, forks into two lobes at the apex in Praecantrix gen. nov. The female subgenital plate, which consists of two separate lobes in all species of Isoplectron, is a square extending into two small lobes in the distal corners in both species of Praecantrix.
Etymology
‘ Praecantrix ’ is Latin for ‘enchantress’, ‘sorceress’. We chose this name because the genus is sister to Pharmacus (‘sorcerer’). Praecantrix is feminine gender.
Description
Adult
MEASUREMENTS. See Table 1. Sexual dimorphism in body length, with females being larger than males by 15% to 20% in both species.
HEAD (Fig. 11C–D). Rounded in the upper half, constricted at the clypeus. Eyes with a straight inner edge facing the scapes of the antennae. Eye colour varies by species. Fastigium divided by a deep median groove; not as prominent above the vertex as in Isoplectron. No visible sexual dimorphism in scapes of antennae or any other head-part. Labial and maxillary palps pale, of varying length, with moderately dense covering of hair.
THORAX. Pronotum an inverted U in cross-section; lateral edges with a pronounced rim. In dorsal view, the pronotum is wider at the posterior end than at the anterior end (Fig. 12J–L).
LEGS. Sexual dimorphism present, with all leg segments longer in females than in males in both species. The ratio of leg length over body length, however, is slightly larger in males than in females. Coxae and trochanters generally of uniform pale colour. Fore and mid femora and tibiae may be uniform pale or variegated; hind legs variegated. Fore coxae with a pronounced lateral anterior spine. Fore tibiae less than half of body length; on average 5% longer than fore femora in both males and females. Fore femora without linear spines above or below, and always without apical spines. Fore tibiae armed below, with one or two linear spines on both anterior and posterior edge in both species. The number of apical spines on the fore tibiae varies by species. Mid legs approximately 5% shorter than fore legs, otherwise with the same proportions in male and females. Mid femora without linear spines above or below; always armed with one retrolateral spine at the apex. A prolateral spine at the apex of the mid femur is always absent. Mid tibiae armed below, with one or two linear spines on both anterior and posterior edge in both species. The number of apical spines on the mid tibiae varies by species. Hind tibiae shorter than or equal to body length, depending on species. Hind femora of same length as hind tibiae. Hind femora generally armed with one to two small linear spines below on both anterior and posterior edges. Hind tibiae armed with anything between 7 and 33 linear spines above (number varies both within and between species), of similar size, on both anterior and posterior edges (Fig. 13J–K). The spines are fused to the shaft of the tibia and are never socketed or articulated. The number of apical spines on the hind tibiae varies by species. Hind tarsi with four segments; first and second segments with a pair of spines on distal end. First and second tarsal segment may be armed or unarmed above, depending on species.
ABDOMEN. Colour and tomentum vary by species.
MALE TERMINALIA. Cerci between 15% and 20% of body length depending on species; rounded at apex, variable in colour, clothed in setae. The subgenital plate looks very similar in both species, roughly pear-shaped, bilobed and widened at apex (see Fig 16).
FEMALE TERMINALIA. Subgenital plate square with rounded lobes protruding at distal corners. Ovipositor pale or reddish-brown, moderately to strongly curved upwards at apex, terminating in a sharp point; between 50% and 70% of body length depending on species. Upper valve always serrated above, strongly so in some species; lower valve with 5 and 7 strong teeth at apex on ventral edge (Fig. 19).
Nymphs
Generally look similar to adults. Due to the small size of the insects and the lack of developed terminalia, nymphs may be impossible to differentiate from their equivalents in Isoplectron.
Distribution
New Zealand: South Island, Stewart Island/ Rakiura, and one record from the Wellington Region in North Island.
description: Published as part of Hegg, Danilo, Morgan-Richards, Mary & Trewick, Steven A., 2024, Revision of the New Zealand cave wētā genus Isoplectron Hutton (Orthoptera: Rhaphidophoridae), with synonymy of Petrotettix Richards and Setascutum Richards, and the description of a new genus, pp. 1-75 in European Journal of Taxonomy 971 on pages 56-57, DOI: 10.5852/ejt.2024.971.2761, http://zenodo.org/record/14451786