Mallinella merimbunenis Koh & Dankittipakul

Dankittipakul, Pakawin, Koh, Joseph K. H. & Singtripop, Tippawan, 2014, Three new species and a new record of the spider genus Mallinella Strand, 1906 from Brunei (Araneae, Zodariidae), Zootaxa 3826 (2), pp. 377-385 : 378-382

Mallinella merimbunenis Koh & Dankittipakul sp. nov.

( Figs 3–4, 8 , 15–21 )

Mallinella sp. A Koh & Leong, 2013: 335.

Material examined. Holotype: ♂, BRUNEI, Tutong: Tasek Merimbun Heritage Park, Zone C3, mixed dipterocarp forest (N04°32′ 24″, E114°39′ 19″), 7 July 2008, J.K.H. Koh leg. (BM, JK.08.06.07.0021). Paratypes: BRUNEI, Temburong: Sungai Batu Apoi, river bank along disturbed forest (N04°42′ 19″, E115°07′ 13″), 17 June 2007, J.K.H. Koh leg., 1♀ (BM, JK.07.04.17.3008). Tutong: Tasek Merimbun Heritage Park, Zone C2, Sungai Melunchur, Base Camp I, mixed dipterocarp forest (N4O35’13 E114O41’14), 25 March 2012, J.K.H. Koh leg., Kampung Bukit, foliage in logged forest (N04O35'31" E114O37'10"), 30 September 2006, J.K.H. Koh leg., 1♀ (LKCNHM, JK.06.09.30.0066). Temburong: Sungai Esu, vegetation along stream in primary mixed dipterocarp forest (N04O32’17 E115O09’35), 24 October 2007, J.K.H. Koh leg., 1♂ (LKCNHM, JK.07.10.24.0016). Kampong Labu, foliage in disturbed forest (N04O45’41 E15O10’51), 10 November 2008, J.K.H. Koh leg., 1♀ (LKCNHM JK.08.11.10.1001). Perdayan Forest Reserve, foliage in lowland mixed dipterocarp forest (N 0 4 O45’41 E115O10’51), 20 April 2012, J.K.H. Koh leg., 1♀ (LKCNHM, JK.12.04.20.0020). Bandar Seri Begawan : Wasai Sungai Akar, foliage in disturbed secondary forest (N04O56’50 E114O59’13), 9 July 2011, J.K.H. Koh leg., 1♂ (LKCNHM, JK.11.07.09.0023).

Diagnosis. Males of M. merimbunenis sp. nov. can be easily recognised by the dark, elevated, circular tubercle on the proximal dorsal surface of femora I–III ( Fig. 4 ), in combination with posterior metatarsi distinctly longer than femora, as well as their distinctive leg colour pattern (see species description below). These tubercles are stridulatory organs ( Dankittipakul et al. 2012; Jocqué 2005) of which three pairs are present also in male specimens of M. annulipes (Thorell, 1892) , found in Singapore, peninsular Malaysia, and in the province of Riau Islands of Indonesia. However, they are absent in the closely related M. albomaculata ( Bosmans & Hillyard, 1990) (also from Borneo, type deposited at NHML, examined). Males of this new species are separated from those of the closely related M. albomaculata by the smaller RTA ( Fig. 17 ) and the larger distal extremities on both rami of the embolus ( Figs 15–16 ). Females resemble those of M. albomaculata ( Fig. 7 ) in possessing the deeply invaginated anterior margin of the epigyne and the distinctly broad lateral lobes. They can be distinguished by the longer median groove reaching the posterior margin of the epigynal septum ( Fig. 8 ) and by the different configuration of the internal genitalia ( Figs 18–21 ).

Etymology. The specific epithet is derived from the type locality, Tasek Merimbun, a wildlife sanctuary and designated ASEAN Heritage Park in Tutong District, Brunei Darussalam.

Description. Male holotype. Total length 6.9; prosoma 3.1 long, 2.8 wide; opisthosoma 3.8 long, 2.6 wide. Leg measurements: I 13.0 (3.4, 0.8, 3.2, 3.4, 2.2), II 12.2 (3.2, 0.8, 3.0, 3.2, 2.0), III 12.0 (3.0, 0.6, 2.9, 3.1, 2.4), IV 16.2 (3.8, 0.8, 4.2, 4.4, 3.0). Eyes circular, pale, from above AER straight, PER strongly procurved. MOQ longer than wide, wider in front than behind. Eye sizes and interdistances: AME largest, others subequal; AME separated by their diameter or less, about their diameter to ALE; PME smallest, separated by 1.5 diameter, from PLE by 2.5 diameter; ALE from PLE by their radius.

Coloration and pattern. Prosoma strongly convex, relatively high, widest at coxae II, in profile highest mid distance between PME and fovea, integument smooth. Fovea deep, longitudinal. Carapace dark reddish brown, distinctly darker peripherally. Chilum trapezoidal, orange, lined with few hairs. Chelicerae, labium and sternum reddish brown. Gnathocoxae brown, pale distally. Leg coxae white; femora dark green, proximally with white dorsoprolateral band running obliquely; dark, circular tubercle present on dorsoproximal portion of legs I–III ( Fig. 4 ); patellae to tibiae brown.

Opisthosoma sepia, mottled with white spots: Medially with five pairs, first pair represented by two irregularshaped spots, second to fifth pairs by oval spots; peripherally with three pairs of oblong spots; posteriorly with two distinctly large spots situated behind fifth median pair. Dorsal scutum dark brown, calcareous, represented by longitudinal band with mesolateral concavities.

Palp ( Figs 15–17 ). Palpal tibia relatively short, with broad ventral ridge. RTA digitiform, short and slender, clearly separable from palpal tibia in ventral view, gradually tapering towards blunt apex in retrolateral view. Tegular spine absent. TA rostrate; bifid apical process elongated, obliquely directed mesad, with mesal branch twice as long as lateral branch; apico-retrolateral flange subtriangular, curved inwards, apex pointing prolaterad; posterior tooth triangular, apex sharply pointed, directed anteriad. Embolic base originating at 270°. Embolus broad, with basal groove, divided into two rami near base; mesal ramus subterminally narrow, its extremity bladelike; lateral ramus distally expand, resulting in beak-shaped flange.

Female paratype. Total length 7.6; prosoma 3.6 long, 3.0 wide; opisthosoma 4.0 long, 3.4 wide. Leg measurements: I 13.5 (3.5, 0.8, 3.0, 3.4, 2.8), II 12.3 (3.3, 0.8, 2.6, 3.2, 2.4), III 11.9 (3.0, 0.6, 3.0, 3.1, 2.2), IV 16.2 (3.8, 0.8, 4.0, 4.6, 3.0).

Coloration and pattern ( Fig. 3 ). Carapace dark chestnut brown. Chelicerae, mouthparts and sternum orangebrown. Legs with pale yellow coxae; femora bicolored, proximal portion pale, median and distal portion dark green, without semi-circular tubercle on legs I–IV; other segments brown.

Opisthosoma almost black, mottled with white spots: Medially with five pairs, first to fourth pairs represented by oblique oval spots, spots of first and second pairs widely separated, spots of third and fourth pairs situated close together, fifth pairs onwards fused together, represented by short median band; peripherally with three pairs of oblong spots; posteriorly with two distinctly large spots situated behind fused sixth pair. Dorsal scutum absent.

Genitalia ( Figs 8 , 18–21 ). Epigynal plate bipartite, deeply invaginated anteriorly, with median incision almost reaching rebordered posterior margin. Lateral borders distinctly enlarged, extending inwards, apex broad and blunt. Insemination ducts relatively short, almost indistinct. Spermathecae heavily sclerotised, pyriform in ventral view, with small circular elevation situated posteriorly.

Natural history. Type specimens were invariably collected by beating foliage along hiking trails at eye level. A more thorough search is required to investigate if they also inhabit the litter layer, as all other Mallinella reportedly do ( Dankittipakul et al. 2012).

Distribution. The species is common and widespread in primary and secondary forests in all four districts in Brunei, viz., Bandar Seri Begawan , Tutong, Temburong and Belait (juveniles only, not listed under “Material Examined”). Given the fact that it is so common in Brunei, it will be not surprising that it will be found at least in Malaysia’s Sarawak, as part of it straddles between Brunei’s districts of Belait and Temburong.

Figures

FIGURES 1 – 3. 1 – 3. Habitus. 1. Mallinella myrmecophaga sp. nov., female holotype. 2. M. platyrhyncha sp. nov., female holotype. 3. M. merimbunenis sp. nov., female paratype.

FIGURES 4 – 11. 4. Leg I – III, showing tubercle (indicated by arrow). 5 – 9, 11. Epigyne, ventral. 10. Internal female genitalia, anterior. 4. Mallinella merimbunenis sp. nov., male holotype. 5. M. bigemina Dankittipakul, Jocqué & Singtripop, 2012, new material from Brunei. 6. M. bigemina, female holotype. 7. M. albomaculata (Bosmans & Hillyard, 1990), female paratype. 8. M. merimbunenis sp. nov., female paratype. 9 – 10. M. myrmecophaga sp. nov., female holotype. 11. M. platyrhyncha sp. nov., female holotype.

FIGURES 12 – 21. 12, 18. Internal female genitalia, dorsal. 20. Ditto, lateral. 13. Left spermatheca, anterior. 14, 21. Right spermatheca, contralateral. 15. Male palp, prolateral. 16. Ditto, ventral. 17. Ditto, retrolateral. 19. Right spermatheca, anterior. 12 – 14. Mallinella bigemina Dankittipakul, Jocqué & Singtripop, 2012, new female from Brunei. 15 – 17. M. merimbunenis sp. nov., male holotype. 18 – 21. M. merimbunenis sp. nov., female paratype. Scale bar: 0.1 mm (15 – 17); 0.25 mm (12 – 14, 18 – 21).