Maratus combustus Schubert 2019, sp. nov.
Creators: name: Schubert, Joseph
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Salticidae
Maratus
Maratus combustus

description: Maratus combustus sp. nov.
(FIGURES 2B, 10 A–F, 11A–D, 12A–C, 13A–F, 14A–D, 15A–C, 16A–B)
Material examined. MALE HOLOTYPE (WAM–T147351) from Australia, Western Australia Mount Romance, 34°51'11.0"S, 117°11'12.0"E, 123m, M. Duncan, 25 Sep. 2018. PARATYPES: 2 male, 2 female (WAM-T147352), same collection data as holotype.
Etymology. The specific name (combustus, Latin, m., participle, English translation: burnt) refers to the burntorange colour of the scales on the dorsal opisthosomal plate.
Diagnosis. This species belongs to the Maratus vespa group (Otto & Hill, 2017B), with respect to the presence of many long bristle-like setae on legs III of the male, and the courtship display of the male which rapidly turns from side to side with a raised opisthosoma and extended large, lobate lateral opisthosomal flaps, displaying to females at close proximity (within millimetres). Maratus combustus can be distinguished from other males of the group by its unique dorsal opisthosomal pattern. Females of M. combustus are similar to other females in the M. vespa clade and identification is not possible without association with a male. The structures of the external male and female genitalia of M. combustus are of no use in distinguishing them from other Southwestern Australia endemic Maratus species.
Description. Male (WAM–T147351). Carapace mostly black and glabrous; median thoracic tract comprised of white scales extends from rear slope of carapace to between the PLE (may be worn in some specimens, see Figure 15C); carapace rimmed with well-defined marginal band comprised of white scales (Figure 10C and F); ocular quadrangle region with dense cover of grey scales and interrupted by seven patches of red scales; two patches of red scales at rear margin of ocular quadrangle with one smaller patch between them; two smaller patches of red scales at midline of ocular quadrangle positioned parallel to each of the AME; larger patches of red scales extend from directly behind each of the PLE (Figure 10A).
PME closer to PLE than to ALE; AME bordered with grey-white scales; ALE bordered with bright red scales dorsally and grey-white scales laterally and below; long white setae project downwards from below anterior median eyes forming triangular shape; clypeus covered with short, white setae (Figures 10A and 11C); chelicerae dark brown to black and glabrous; coxae and labium dark brown and glabrous; endites dark brown and glabrous; sternum dark brown (Figure 11B) with light covering of fine, white setae.
Dorsal opisthosomal plate distinctively patterned with thick cover of scales; five tracts of scales, alternating in colour between red and blue and bordered by black extend from each anterolateral edge of dorsal opisthosoma towards median dorsal opisthosoma; light cover of mixed white and tan setae between each set of tracts (may be worn in some specimens, see Figure 15 A–C); area below with thick cover of burnt orange/tan scales; triangular shape of gold scales bordered by black scales situated near posterior margin of dorsal opisthosomal plate; posterior margin of opisthosoma with distinctive stripes of scales alternating in colour between tan and white and bordered by black; prominent tufts of long setae extend beyond rear margin of dorsal opisthosomal plate, the colour of each of them corresponding with above posterior marginal stripes (Figure 10B).
Lateral opisthosomal flaps large, lobate and ornamented with bright orange scales at upper margin, otherwise covered with dull purple scales; prominent tuft of long white setae project posteriorly from lateral margin of each opisthosomal flap, visible during courtship (Figure 2B); tuft of white setae above black spinnerets; ventral opisthosoma dark grey and scattered with short, creamy coloured setae.
Legs I and II subequal in length; legs III and IV longer; legs III by far longest. Legs I, II, and IV ringed with alternating bands of dark brown and white setae; legs III with less distinct and less frequent rings; anterior surface of femora of legs III with a thick cover of short, white setae; femora, patellae, and tibiae of legs III ornamented with heavy fringing of long white setae; tarsi of legs III tipped with white setae. Pedipalp covered dorsally with long off-white setae; relatively large palpal bulb with retrolateral sperm duct loop, large retrobasal tegular lobe, finger-like retrolateral tibial apophysis; embolus with pointed inner apex beneath thicker outer apex (Figure 12 A– C).
Female (WAM-T147352). Ocular quadrangle region with incomplete cover of red-brown and white setae; area posterior to ocular quadrangle black and mostly glabrous; incomplete bands of white setae extend from PME to rear margin of carapace; area below dark brown to black and mostly glabrous; rim of carapace glabrous and lacking marginal band (Figure 13A and B).
Anterior eyes bordered with red-brown and white scales dorsally, and white scales laterally and below; PME closer to PLE than to ALE; long white setae project downwards from below AME forming triangular shape; clypeus covered with short, white setae (Figure 13A); chelicerae dark brown to black and glabrous; coxae, endites, and labium dark brown, translucent and mostly glabrous; sternum medium-dark brown (Figure 14A) with light covering of fine, white setae.
Dorsal opisthosoma light brown with incomplete cover of off-white and dark brown setae; central spot of offwhite setae on dorsal opisthosoma; lateral and posterior edges of dorsal opisthosoma bordered with narrow band of light brown and white setae; spinnerets dark brown (Figure 14A); lateral and ventral opisthosoma light brown and covered with small dark spots (Figure 14A).
Legs I and II subequal in length; legs III and IV longer; legs III longest. Integument of each leg with alternating bands of light brown and dark brown; ventral femoral surface of each leg distinctively marked with dark bands (Figure 14A); each leg with light cover of short white setae; tarsi of each leg tipped with dark brown setae; pedipalps light brown and translucent with incomplete cover of off-white setae (Figure 13A). Epigynum with pair of large ovate fossae separated by septum; ovate posterior spermatheca behind each fossa; sclerotized ducts present anterior to each spermatheca (Figure 14D).
Variation. The size of the triangular shape of scales on the lower dorsal opisthosoma of males may vary. The angle at which the tracts of scales at the anterior margin of the dorsal opisthosoma converge towards the middle varies in the additional paratype male specimens. The scales on the surface of the dorsal opisthosoma between these lines may be worn (Figure 15 A–C).
The width of the light-coloured band on the lateral opisthosoma of females may vary. The median thoracic tract may be more or less distinct due to scales rubbing off (16A and B).
Dimensions. Male. Total length: 3.67–3.78 (3.72±0.03, n=3). Carapace length 1.83–1.96 (1.91±0.04, n=3). Opisthosoma length 1.72–1.86 (1.80± 0.04, n=3). Leg I length: 2.84–2.86 (2.85±0.01, n=3). Leg II length: 2.84– 2.87 (2.85±0.01, n=3). Leg III length: 4.1 9–4.31 (4.25±0.03, n=3). Leg IV length: 3.74–3.81 (3.76±0.02, n=3).
Dimensions. Female. Total length: 4.95–4.99 (4.97±0.02, n=2). Carapace length 2.11–2.27 (2.19 ±0.08, n=2). Opisthosoma length 2.72–2.84 (2.78± 0.06, n=2). Leg I length: 2.68–2.72 (2.70±0.02, n=2). Leg II length: 2.65–2.67 (2.66±0.01, n=2). Leg III length: 4.43–4.48 (4.46±0.03, n=2). Leg IV length: 3.92–4.00 (3.96±0.04, n=2).
Distribution. Known only from near Mount Romance, Western Australia.
Courtship display. The male elevates legs III, holding them straight upwards and holding them in place for the duration of the courtship display. The pedipalps are held apart, exposing the chelicerae. The opisthosoma is elevated and waved, and the lateral opisthosoma flaps are extended. As the female approaches, the lateral opisthosomal flaps are repeatedly retracted and extended whist the opisthosoma remains elevated and waving. (Figure 2B). (Note: only partial courtship display observed, the males may exhibit a more complete courtship display with multiple modes of courtship).
description: Published as part of Schubert, Joseph, 2019, Three new peacock spiders from Southwestern Australia (Araneae: Salticidae: Euophryini: Maratus Karsch, 1878), pp. 81-100 in Zootaxa 4564 (1) on pages 88-94, DOI: 10.11646/zootaxa.4564.1.3, http://zenodo.org/record/2588669