Tuesday, March 30, 2021

[Arachnida • 2021] Maratus nemo • A New Wetland Species of Peacock Spider (Araneae, Salticidae, Euophryini) from South Australia



Maratus nemo Schubert, 2021

Abstract
A new species of peacock spider, Maratus nemo sp. nov., is described from the vicinities of Mount McIntyre and Nangwarry, South Australia. Unusual among members of its genus, the new species appears to inhabit ephemeral wetland complexes on marshy vegetation in shallow water. The discovery of Maratus nemo sp. nov. is one of several recently described species attributed to the growing interest in amateur invertebrate macrophotography, with putative new species brought to attention of taxonomists through social media engagement.

Key Words: Taxonomy, jumping spider, salticid, euophryine, systematics, morphology


Figure 1. Habitus of living paratype male Maratus nemo sp. nov. (SAM NN30709)
A anterolateral view B lateral view C dorsal view D anterior view E anterolateral view F anterior view.

Figure 4. Habitus of living paratype female Maratus nemo sp. nov. (SAM NN30710)
 A dorsolateral view B dorsal view C anterolateral view D lateral view E posterolateral view F anterior view.

 Maratus nemo sp. nov.
 
Diagnosis: Males of Maratus nemo share some similarities to members of the Western Australian Maratus personatus group (Otto and Hill 2019; Otto and Hill 2021) in having the anterior ocular area ornamented with coloured scales, so as to form a ‘mask’, and in lacking opisthosomal colouration or flaps. It is thus tentatively placed in this species group (see Girard et al. 2021; Otto and Hill 2021; and Schubert 2020 about the tentative nature of subgeneric clades within Maratus). Maratus nemo, however, can be readily separated from members of this species group and all other congeners by the following combination of characters: bright orange field of scales covering the clypeus and anterior ocular region (Figs 1A‒F, 2A‒D, 6A‒D) light covering of fine white setae on the carapace, legs, and mostly glabrous dorsal opisthosomal plate (Figs 1A‒F, 2A‒D, 6A‒D); relatively compact embolic disc by which the inner and outer rings of the embolus are in close contact or fused to form a single heavy apex (Fig. 3A‒C); dark lateral sclerite proximal to the embolus; distinct thick extension or flange along the proximal arc of embolus (Fig. 3A). Females of M. nemo are similar to other Maratus females and identification may not be possible without association with a male.

Etymology: The specific epithet refers to the colouration of the male of this species which resembles that of the character Nemo in the 2003 Walt Disney film ‘Finding Nemo’ ‒ to be treated as a noun in apposition.

Figure 6. Sequential frames from a video of the courtship display of paratype male Maratus nemo sp. nov. (SAM NN30709)
A stationary male focusing on a nearby female B left leg III extended and waved C left leg III extended and flexed and slow opisthosomal bobbing D both legs III extended and waved and opisthosoma is rapidly vibrated on the surface of the leaf creating an audible sound.

 Figure 8. Habitat of Maratus nemo sp. nov. in the vicinity of Mount McIntyre, South Australia. (Photos provided by Sheryl Holliday, used with permission)
A ephemeral wetland complex habitat at the type locality B marshy vegetation from the type locality
C Maratus nemo sp. nov. male in situ Maratus nemo sp. nov. female in situ.
 
Distribution and habitat: Known only from 9.5 km SSE of Mount McIntyre, 9.4km SSE of Mount McIntyre, and 14.1km E of Nangwarry (Fig. 9). Curiously, M. nemo was found in an ephemeral wetland complex on marshy vegetation in shallow water (Fig. 8). No other species of Maratus are known to occupy such habitats.



 Joseph Schubert. 2021. Maratus nemo: A New Wetland Species of Peacock Spider from South Australia (Araneae, Salticidae, Euophryini). Evolutionary Systematics. 5(1): 71-80. DOI: 10.3897/evolsyst.5.64922