Myrmarachne helensmithae, 2017

Tripathi, Rishikesh, Jose, Athira, Nafin, Karunnappilli Shamsudheen, Babu, Nishi & Sudhikumar, Ambalaparambil Vasu, 2017, Revision of eastern Australian ant-mimicking spiders of the genus Myrmarachne (Araneae, Salticidae) reveals a complex of species and forms, Zoological Journal of the Linnean Society 179 (3), pp. 642-676 : 652-654

publication ID	https://doi.org/10.1111/zoj.12439
DOI	https://doi.org/10.5281/zenodo.14806028
persistent identifier	https://treatment.plazi.org/id/C06D1236-FA2C-4802-FF76-61B77BA5FDB3
treatment provided by	Plazi (2025-02-04 21:25:40, last updated by Guilherme 2025-02-05 11:47:31)
scientific name	Myrmarachne helensmithae
status	sp. nov.

Treatment

MYRMARACHNE HELENSMITHAE PEKAR View in CoL SP. NOV.

Type material

Australia. QLD: 1♂ holotype ( QMB, S100087 View Materials ) (23 December 2011; I. Macaulay) Cairns GoogleMaps (16° 54 0 50.62 ″ S, 145° 46 0 1.72 ″ E); 1♂, 1♀ paratypes ( AMS) (9 January 2012; I. Macaulay) Cairns (16° 54 0 50.62 ″ S, 145° 46 0 1.72 ″ E). NT: 1♀ paratype ( QMB, S100126 View Materials ) (15 January 2013; I. Macaulay) Darwin (12° 27 0 58.41 ″ S, 130° 50 0 23.22 ″ E) .

Material examined

Australia. NT: 1♂ ( QMB, S100123 View Materials ) (4 December 2014; I. Macaulay) Darwin (12° 27 0 58.41 ″ S, 130° 50 0 23.22 ″ E) ; 1♂ ( AMS, KS.13619) (3 August 1983; C. Gentle, T. O’Donnell) Kakadu Nat. Park GoogleMaps , Arnhem Land (12°25 0 S, 132°18 0 E) ; 1♂ ( QMB, S399 View Materials ) (22 February 1988; R. Wildman) same locality (12° 25 0 59.988 ″ S, 132°9 0 E) ; 1♂ ( MUB) (1 February 2013; I. Macaulay) Litchfield NP near Darwin (13° 9 0 47.04 ″ S, 130° 40 0 58.04 ″ E) . QLD: 1 juv. ( CRW) (24 February 2014; I. Macaulay) Cairns (16° 54 0 50.62 ″ S, 145° 46 0 1.72 ″ E) ; 1♀ ( CRW) (15 March 2013; I. Macaulay) same locality ; 1♂ ( CRW) (8 April 2014; I. Macaulay) Townsville (19° 17 0 29.54 ″ S, 146° 46 0 55.07 ″ E) ; 1♂ ( QMB, S100089 View Materials ) (9 November 2013; I. Macaulay) same locality ; 1♂ ( QMB, S100088 View Materials ) (10 November 2012; I. Macaulay) same locality ; 1♂ ( QMB, S100086 View Materials ) (13 February 2013; I. Macaulay) same locality . 6♂♂, 15♀♀, 10 juv. ( MUB) (22 � 27 March 2014; G. Corcobado, S. Pekar) Cairns, Cairns Botanic Gardens GoogleMaps (16° 53 0 57.563 ″ S, 145° 44 0 59.953 ″ E) ; 1♀ ( AMS, KS.106040) (20 September 2008; G. Cocks) Hermit Park (19° 16 0 58 ″ S, 146° 48 0 02 ″ E) .

Etymology

The name is a matronym in honour of Helen Smith for her generous help with this revision of Myrmarachne .

Diagnosis

This species is morphologically most similar to M. lupata , M. macaulayi sp. nov., and M. smaragdina . Both sexes of this species can be distinguished from the other species by orange/black body coloration. Males can be further differentiated by long and straight chelicerae, small apophysis on the fang, homogeneous dentition of chelicerae, absence of tibial groove below RTA. Females can be recognized by less twisted copulatory ducts. This species is not diagnosable using DNA data (see below).

Description

Male: Measurements (N = 8): total body length 7.3 mm (5.6 – 9.2 mm), carapace length 2.4 mm (1.9 – 3.0 mm), carapace width 1.4 mm (1.1 – 1.6 mm), chelicera length 2.4 mm (1.7 – 3.0 mm), abdomen length 2.4 mm (1.9 – 3.1 mm), PTB = 1. Colour ( Fig. S1F View Figure 1 ): chelicerae orange, covered with black sparse hairs, brown at the tip; carapace orange, but eyes surrounded by black patches; white hairs around AME, sternum, endites, and palpal segments yellow; leg segments orange, but Pt I and Ti I with blackish stripe on prolateral side, Mt I and Pt IV with black stripe on lateral and prolateral sides; abdomen orange but posterior half black. Morphology: chelicerae protruding, with six strong teeth on prolateral margin, nine small teeth on retrolateral margin; fangs straight with a small ventral apophysis near to base, tip curved ( Fig. 6E, F View Figure 6 ); prosoma elongate ( Fig. 6A View Figure 6 ), carapace with a constriction behind PLE, cephalic part dorsally flat and higher than thoracic part ( Fig. 6B View Figure 6 ); carapace frontally with an apophysis on lateral side; leg spines: Ti I with three or four ventral pairs, Mt I and II and Ti II with two ventral pairs of spines; abdomen elongate with a constriction and two dorsal scuta ( Fig. 6B View Figure 6 ); palpal cymbium oval, with one apical spine, tegulum rather small, round, embolus coiled 1.5 times, tip of embolus straight, rather short, pointing forwards ( Figs 2E, 6G View Figure 6 ); RTA tiny, tip laterally hooked, flat surface on the prolateral side of Ti below RTA; flange not developed ( Figs 2F, 6H View Figure 6 ).

Female: Measurements (N = 14): total body length 5.2 mm (4.2 – 7.1 mm), carapace length 2.2 mm (2.1 – 2.5 mm), carapace width 1.1 mm (1.0 – 1.2 mm), chelicera length 0.6 mm (0.5 – 0.7 mm), abdomen length 2.4 mm (1.8 – 3.0 mm). Colour ( Fig. S1G View Figure 1 ): as in males, but carapace laterally with wedge of white hairs in the constriction ( Fig. 6C, D View Figure 6 ). Morphology: as in males, but chelicerae small, lateral margin of chelicerae with between five and seven teeth, retrolateral margin with between six and ten teeth; epigyne with two small atria separated by a septum, atria 1.5 times wider than septum, median pocket rather rectangular, situated below septum ( Figs 3C View Figure 3 , 6I View Figure 6 ); spermathecae elongate, copulatory ducts moderately twisted above atria ( Fig. 6J View Figure 6 ).

Natural history

This species occurs on foliage, where it builds silken retreats. It imitates the ant Opisthopsis haddoni Emery, 1893 .

Distribution

Australia: QLD, NT ( Fig. 4C View Figure 4 ).

Figures

Figure 1. Myrmarachne bicolor: A, right male chelicera, dorsal view; B, left male chelicera, ventral view; C, left male palp, ventral view; D, male palpal tibia, dorsal view; E, epigyne, ventral view; F, vulva. Scale barss: 0.2 mm.

Figure 3. Scanning electron microscopy (SEM) of females: A, Myrmarachne bicolor, epigyne, ventral view; B, Myrmarachne erythrocephala f. erato, epigyne, ventral view; C, Myrmarachne helensmithae sp. nov., epigyne, ventral view; D, Myrmarachne luctuosa f. aeneopilosa, epigyne, ventral view; E, Myrmarachne macleayana f. robsoni, epigyne, ventral view.

Figure 4. Maps of distribution: A, Myrmarachne bicolor; B, Myrmarachne erythrocephala; C, Myrmarachne helensmithae sp. nov.; D, Myrmarachne luctuosa; E, Myrmarachne lupata; Myrmarachne milledgei sp. nov.; F, Myrmarachne macaulayi sp. nov.; G, Myrmarachne macleayana; H, Myrmarachne smaragdina; I, Myrmarachne striatipes; J, Myrmarachne zabkai sp. nov. The size of the points is scaled according to abundance: 1–3 individuals (small); 4–10 individuals (medium);> 10 individuals (large).

Figure 6. Myrmarachne helensmithae sp. nov.: A, male habitus, dorsal view; B, male habitus, lateral view; C, female habitus, dorsal view; D, female habitus, lateral view; E, right male chelicera, dorsal view; F, left male chelicera, ventral view; G, left male palp, ventral view; H, male palpal tibia, dorsal view; I, epigyne, ventral view; J, vulva. Scale bars: A–D, 2 mm; E–J, 0.2 mm.