Maratus lentus, Otto & Hill, 2017

Otto, Jürgen C. & Hill, David E., 2017, Five new peacock spiders from eastern Australia (Araneae: Salticidae: Euophryini: Maratus Karsch 1878 and Saratus, new genus), Peckhamia 147 (1), pp. 1-86 : 37-44

Maratus lentus , new species

Type specimens. The holotype male (♂ #1), three paratype males (♂ #2-4), and five paratype females (♀ #1-5) were collected near Copeton , New South Wales (S29.94025°, E150.93786°, 13 SEP 2015, coll. M. Doe, M. Duncan, A. Fletcher). All types will be deposited in the Australian Museum, Sydney .

Etymology. The species group name ( lentus, Latin , m., adjective, English translation slow) refers to the slow and deliberate movement of the adult male during courtship.

Diagnosis. M. lentus is very close to M. cinereus but males can be identified by the orange colour of their eye region and dorsal opisthosomal plate (fan), and the presence of a wide, grey dorsal band along each lateral margin of the fan. M. lentus males (4.0- 4.1 mm in length) also tend to be smaller than M. cinereus (4.2-4.5 mm). Courtship display by males of the two species is similar with respect to general posture, intermittent extension or kicking of one leg III, and movement of one pedipalp to expose the underlying paturon of the ipsilateral chelcera. However, M. lentus males do little kicking with legs III and mostly wave their elevated fan from side to side with the spinnerets extended and separated above the fan. Most active movement during display by the male M. cinereus is associated with frequent kicking, wheras active movement by M. lentus is associated with movement of the fan from side to side (waving). Female M. lentus look much like female M. cinereus , so capture of the males is a prerequisite for identification.

Description of male ( Figures 39-42 ). Males are 4.0- 4.1 mm in length (n=4). The chelicerae and clypeus are brown, glabrous, and translucent. Long white to light orange setae extend anteromedially below the anterior eye row. The eye region and sides of the carapace below the lateral eyes is uniformly covered with light orange to light brown scales. This scale cover ends abruptly behind the posterior eye row, and the posterior carapace is mostly black except for a wide tract of white scales behind each PLE. Behind the PLE the sides of the carapace are black and glabrous, and there is no marginal band to conceal the lateral rims of the carapace, but two short bands of white scales extend dorsally from the lateral rim on each side. The PME are almost equidistant between the ALE and PLE.

The dorsal opisthosomal plate (fan) has a triangular central area, wide at front and tapering to a vertex at the rear, covered with light orange scales with many scattered, small red-orange spots ( Figures 39-40 ). On either side of this is a broad gray lateral band terminating at the rear with a small black spot, and flanking each lateral band is a narrow fringe of white to off-white setae. The sides of the opisthosoma are covered with long white to off-white setae ( Figure 53 : 1-2). The ventral opisthosoma is light brown with a sparse cover of short off-white setae, with a prominent black line on either side ( Figure 49 : 7).

Legs I and II are about the same length, covered with off-white to light-orange scales and setae. The cuticle of legs I and II is light brown and translucent, except for narrow dark rings that highlight the metatarsus and small but distinct "cuffs" of setae associated with the proximal tarsus. Legs III and IV are longer than legs I and II, and legs III are the longest. Legs III and IV are covered with white to off-white or light orange setae, but legs III have a narrow black anterior stripe extending from the base of the femur to the distal end of the tibia. As with M. cinereus , this stripe is visible from the front when the respective leg is elevated during courtship.

Dorsally the pedipalps have a dense cover of long light-orange setae ( Figures 39 : 3, 40: 2). Distal setae of the pedipalps are grey. As in other members of the anomalus group, the apex of the outer ring of the pedipalp is blunt or bifurcated at the end, and below this the apex of the short inner ring is pointed ( Figure 42 ).

Description of female ( Figures 43 -47). Females are 4.1-5.2 mm in length (n=4). The chelicerae, clypeus, and sides of the carapace are light brown, translucent, and glabrous. Long white setae originating below the anterior eyes extend anteriomedially over the chelicerae. The upper carapace is dark, as is a glabrous, broad median band extending to the rear of the carapace. The eye region and upper carapace below the lateral eyes are covered with light brown to off-white scales. On either side a band of off-white to light brown scales extends toward the rear of each PLE, converging to flank the dark, glabrous median band. The PME are about the same distance from the ALE as from the PLE. The dorsal opisthosoma is covered with off-white to light brown pigmented scales, boldly marked with a series of 5-8 more or less distinct, dark brown or black diagonal lines oriented in a posteromedial direction from the lateral margin, and ending on either side of a median figure that may be defined by a line of lighter spots laterally, and a series of forward-pointing, dark chevrons posteromedially ( Figures 43 -44).

The sides and underside of the opisthosoma are light brown or off-white in colour, with a covering of white scales. The ventral opisthosoma may be clear of markings, or it may be mottled with dark spots ( Figure 45 ). The sternum, coxae, labium, and endites are all light brown and translucent, and mostly glabrous except for a row of white setae around the posterior sternum. Legs I and II are shorter and of similar length, legs III and IV much longer and also of similar length. All legs are light brown, translucent, and mostly glabrous. They are almost completely glabrous ventrally. Above the legs, particularly legs III and IV, bear a moderate cover of off-white scales and setae. The pedipalps are also light-brown, translucent, and bear many longer off-white setae.

The epigynum is typical for members of the anomalus group, with dark or highly sclerotized ducts visible on either side at the rear of each fossa ( Figure 46 ).

Figures

Figure 39. Living holotype (1-3) and paratype (4-9) male Maratus lentus. 3, Note the distinct setal "cuffs" of the proximal tarsi of legs I and II. 4, The black stripe at the front of each leg III is visible from the front when that leg is raised as shown here.

Figure 40. Two living paratype male Maratus lentus (1-7, 8). 1, Note the two short bands or patches of white setae on the right side of the carapace. 2, Most of the carapace is black but the chelicerae and clypeus are brown, translucent, and mostly glabrous as seen here. 6, When preparing to jump Maratus flex their longer legs III against the surface as shown here. This allows them to exert a ground force over a greater distance as legs III are extended in contact with the surface.

Figure 41. Holotype (1-3 & 13) and three paratype (4-5, 6-8 & 14, 9-12 & 15) male M. lentus fixed in alcohol.

Figure 42. Medial to lateral views of the left pedipalp of the holotype (1-4) and two paratype (5-8, 9-12) male Maratus lentus.

Figure 43. Three living female Maratus lentus (1-5, 6-10, 11-12).

Figure 45. Ventral view of three living female Maratus lentus. 1-2, Note the mottling of the ventral opisthosoma in these females.

Figure 46. Ventral view of the epigynum of four female Maratus lentus. Note variation in the shape and relative size of the fossae, width of the septum separating the fossae, shape and size of the large posterior spermathecae, and relative position of the sclerotized ducts on either side of each fossa. In (1) and (3) the medial and lateral ducts are at about the same position relative to the midline. In (2) the medial ducts are well behind the lateral ducts, and in (4) the lateral ducts are well behind the medial ducts. Intraspecific variation like this can be greater than interspecific variation within this group, making the detailed structure of the epigynum of little use for identification at the species level.

Figure 49. Views of display by the holotype male Maratus lentus in front of a female. 2-3, When a single leg III is kicked, it is elevated and flexed as shown here, then extended rapidly. 4-5, Note movement of the extended spinnerets between these sequential photographs. 7, Ventral view showing sparse cover of shorter setae between prominent black marginal bands of the venter, and the inflated base of the spinnerets.

Figure 53. Three views of the holotype male M. lentus mating with a paratype female. Note the long white to off-white setae on the sides of the male opisthosoma, below the dorsal plate or fan.