Myrmarachne macaulayi, 2017

MYRMARACHNE MACAULAYI PEKAR View in CoL SP. NOV.

Type material

AUSTRALIA. QLD: 1♂ holotype ( QMB, S100097 View Materials ) (11 November 2013; I. Macaulay) Ingham   GoogleMaps (18 ° 39 0 18.39 ″ S, 146 ° 9 0 12.67 ″ E). NT: 1♀ paratype ( QMB, S100124 View Materials ) (17 January 2013; I. Macaulay) Darwin (12 ° 27 0 58.41 ″ S, 130 ° 50 0 23.22 ″ E) .

Material examined

Australia. QLD: 1♂ ( MUB) (25 February 2014; I. Macaulay) Cairns (16 ° 54 0 49.72 ″ S, 145 ° 46 0 0.45 ″ E); 1♀ ( MUB) (31 March 2013; I. Macaulay) same locality (16 ° 54 0 50.62 ″ S, 145 ° 46 0 1.72 ″ E); 1♂ ( MUB) (11 March 2014; I. Macaulay) Ingham (18 ° 39 0 18.39 ″ S, 146 ° 9 0 12.67 ″ E); 1♀ ( MUB) (8 November 2012; I. Macaulay) Townsville (19 ° 15 0 11.64 ″ S, 146 ° 48 0 36. 24 ″ E); 1♂ ( QMB, S100096 View Materials ) (14 November 2012; I. Macaulay) Charters Towers (20 ° 4 0 18.24 ″ S, 146 ° 15 0 38.76 ″ E). NT: 1♂ ( QMB, S41425 View Materials ) (10 � 13 July 1979; G. Monteith, D.J. Cook) Mount Gilruth   GoogleMaps , north-east gorge (13 ° 1 0 59.988 ″ S, 133 ° 4 0 59.88 ″ E) .

Etymology

The name is a patronym in honour of Ian Macaulay for collecting this and many other Myrmarachne specimens across Australia.

Diagnosis

Most similar to M. helensmithae sp. nov., M. lupata , and M. smaragdina . Both sexes of this species can be distinguished from the other species by dark-brown to black body coloration and tiny body size. Males can be further differentiated by straight chelicerae, uniform dentition, very tiny apophysis on the fang, undulated margin of tibial groove below RTA. Females can be recognized by massively twisted copulatory ducts. This species is not diagnosable using DNA data (see below).

Description

Male: Measurements (N = 2): total body length 6.6 mm, carapace length 2.3 mm, carapace width 1.3 mm, chelicera length 2.3 mm, abdomen length 2.2 mm, PTB = 0.81. Colour ( Fig. S1K View Figure 1 ): chelicerae shiny, dorsally with white hairs at base and sparse black hairs distally; carapace and abdomen dark brown, eyes surrounded by black patches, white hairs around AME; sternum and endites brown; palpal segments yellow with black stripes; leg segments yellow to brown, banded on sides except for Cx I and II, Pt II, Ta I and II; Cx I and II, Tr IV, pale, Cx II and III, pale with lateral longitudinal black stripes; abdomen with a transverse white stripe at the constriction. Morphology: chelicerae protruding, with five strong teeth on prolateral margin and eight teeth on retrolateral margin; fangs straight with a tiny apophysis ventrally near base ( Fig. 9E, F View Figure 9 ), distally curved; prosoma elongate ( Fig. 9A, B View Figure 9 ), cephalic part of carapace flat and higher than thoracic part, with a constriction behind PLE ( Fig. 9B View Figure 9 ); leg spines: Ti I with three ventral pairs, Mt I, Mt II, and Ti II, each with two ventral pairs; abdomen elongate, with two scuta and a shallow constriction; palpal cymbium oval with one apical spine, tegulum rather large, embolus coiled 1.5 times, tip of embolus straight, rather short, pointing forwards ( Fig. 9G View Figure 9 ); RTA sinusoid, hooked at the tip, flange of RTA developed with undulating margin ( Fig. 9H View Figure 9 ).

Female: Measurements (N = 2): total body length 5.1 mm, carapace length 2.2 mm, carapace width 1.1 mm, chelicera length 0.5 mm, abdomen length 2.5 mm. Colour ( Fig. S1L View Figure 1 ): as in males, but with white wedge at the constriction of the carapace, palp metallically shiny dorsally. Morphology: as in males, but chelicerae small ( Fig. 9C, D View Figure 9 ), with four teeth on prolateral margin and seven teeth on retrolateral margin, palpal Pt and Ta flattened; epigyne with small and round atria, as wide as septum; median pocket wide, triangular with lateral lobes ( Fig. 9I View Figure 9 ); spermathecae elongate, copulatory ducts massively twisted above atria ( Fig. 9J View Figure 9 ).

Natural history

This species seems to imitate the ant Opisthopsis respiciens (Smith, 1865) .

Distribution

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

Remarks

Phenotypic differences from M. smaragdina and M. helensmithae sp. nov. strongly suggest it is a species, not a form.