Ponera leae Forel 1913

Compiled by Warwick Don & Richard Harris

Biostatus: Introduced

Classification

Family:	Formicidae
Subfamily:	Ponerinae
Tribe:	Ponerini
Genus:	Ponera
Species:	leae

Common name(s)

Blind crypt ants (Andersen 2002)

Synonyms (Valentine & Walker 1991)

Ponera caledonica Wilson, Ponera excedra Wilson, Ponera leae subsp. norfolkensis Wheeler, Ponera leae subsp. oculata Wheeler, Ponera leae norfolkensis Wheeler

Origin

Worldwide, there are 32 species of Ponera , known from North America, and Europe east to Japan, Samoa and Australasia. Four species are known from Australia (Shattuck 1999), one of which is Ponera leae. This species was first recorded here in Paihia, Northland, in 1958. Taylor (1967) favours initial entry in ships' ballast using Piha as a port of call in the early days of European settlement.

Green (1992) shed doubt on whether P. leae was still established here, given that no specimens had been recorded in the far north since 1966. However, the cryptic nature of the species and its similarity to Hypoponera mean it could easily be overlooked. In 1997, a single queen was collected at Cable Bay, Nelson, in a pitfall trap set in a kanuka stand (Harris & Berry 2001), possibly as a result of a separate incursion. This recent record is evidence this species is still established in this country, but somewhat removed from the area of initial introduction.

Distribution

The first records of this species comprise five collections from two localities (Paihia and Butterfly Valley, Tauranga Bay) in the far north. The most recent record is from Auckland in 2003.

General Description

Identification

The mandibles in Ponera are triangular, with three enlarged apical teeth followed by numerous small teeth along their inner margins. Antenna with an indistinct to distinct 4 to 5-segmented club often present. The single petiolar node has distinct front, top and rear sides. The underside of this node has a characteristic translucent thin spot near the front and a sharp angle or a pair of small teeth near the rear, which distinguishes it from the similar appearing Hypoponera .

Diagnostic features of the worker

Length 2.5 mm; antennae 12-segmented with a 4-segmented club; eyes minute with a single facet.

[Ponera leae] head. Image: April Nobile (Specimen code: CASENT0172337). www.antweb.org Image — Ponera leae head. Image: April Nobile (Specimen code: CASENT0172337). www.antweb.org

Ponera leae profile. Image: April Nobile (Specimen code: CASENT0172337). www.antweb.org

[Ponera leae] dorsal view. Image: April Nobile (Specimen code: CASENT0172337). www.antweb.org Image — Ponera leae dorsal view. Image: April Nobile (Specimen code: CASENT0172337). www.antweb.org

Biology

Like other small, cryptobiotic ponerines, P. leae nests in rotting logs in forests, or under stones in non-forested areas. Colonies are small (about 30 workers) and larvae (as in Hypoponera eduardi ) are attached to the floor or walls of the nest galleries by glutinous abdominal tubercles. The feeding habits are not known for certain but, like other small ponerines, this species is probably insectivorous (Taylor 1967).

Pest Status

Impacts not known, but considered unlikely to be a pest.