Hormurus macrochela Monod, 2013

Monod, Lionel, Harvey, Mark S. & Prendini, Lorenzo, 2013, Stenotopic Hormurus Thorell, 1876 scorpions from the monsoon ecosystems of northern Australia, with a discussion on the evolution of burrowing behaviour in Hormuridae Laurie, 1896, Revue suisse de Zoologie 120 (2), pp. 281-346 : 314-327

Hormurus macrochela Monod , n. spec. Figs 22-31, Table 3

Liocheles waigiensis: L. E. Koch, 1977 (misidentification, part): 171, 172. – Volschenk et al.,

2001: 162 (misidentification, part).

HOLOTYPE: QM-S59212; Ƌ; Australia, Queensland, Palm Island , site 4, 18º40'S, 146º40'E; 22.II.2001; 100 m, rainforest, G. B. Monteith.

PARATYPES: QM-S17042; 1 ♀, 3 imm.; Palm Island , 18º50'S, 146º40'E; L. Bancroft. – QM S17088 ; 1 imm.; idem; IX.1923; H. A. Longman. – QM-S59206; 1 Ƌ, 1 ♀; Palm Island, site 1, 18º50'S, 146º40'E; 20-21.II.2001; 450 m, rainforest, G. B. Monteith .

OTHER MATERIAL: NHML 1890.7.1. 216-221; 1 Ƌ; Australia; Keyserling. – NHML 1925.IX.12. 1-4; 1 Ƌ 1 ♀, 2 imm.; Magnetic Island [19º08'19''S, 146º50'04''E]; G. F. Hill. – ESV 3370; 1 Ƌ; VI.1992; vine forest, E. S. Volschenk. – MHNG, without registration number; Magnetic Island, 19º10'S, 146º50'E; 4 Ƌ, 7 ♀, 2 imm.; 28-29.XI.2004; 41 m, vine thicket along dry creek, in rock crevices (very narrow or in between stones), R. Wyss & L. Monod . – QM; 1 Ƌ, 1 ♀; same data as previous record. – AMCC LP 5555; 1 imm.; same data as previous record. – NTM, without registration number; 1 ♀; Orpheus Island [18º37'20''S, 146º29'57''E]; XI.1982; R. Tuesley .

ETYMOLOGY: The name macrochela is constructed from the Greek words makros [long] and chele [claw]. It is an invariable noun in apposition and refers to the extreme elongation of the male pedipalps.

DIAGNOSIS: Hormurus macrochela differs from other Australian hormurids as follows. Sexual dimorphism of the pedipalps is more pronounced in H. macrochela than in other species except H. longimanus. The ventrointernal carina of the pedipalp chela manus is distinct and coarsely granular in H. macrochela whereas it is weakly developed and smooth or nearly so in other species except Liocheles litodactylus

FIG. 22

Hormurus macrochela n. spec., male, dorsal aspect, reconstruction based on scientific illustrations and photographs of live specimens. Scale, 5 mm.

FIG. 23

Hormurus macrochela n. spec., habitus, dorsal (A, B) and ventral (C, D) aspect. (A, C) Holotype male (QM-S59212). (B, D) Paratype female (QM-S59206). Scale, 10 mm.

Monod & Volschenk, 2004. The pedipalp chela trichobothrium Esb is situated close to trichobothrium Est in H. macrochela whereas it is situated midway between the Eb group of trichobothria and Est in other species except H. ischnoryctes . The mesosomal post-tergite VII is granular at least posteriorly in H. macrochela but smooth or nearly so in other species except H. longimanus. An accessory hook, present on the ental surface of the distal lobe of the hemispermatophore capsule in H. macrochela , is absent in other species except H. ischnoryctes and H. ochyroscapter .

DESCRIPTION OF ADULT MALE: Colouration: Dorsal surface of chelicera manus orange, with darker infuscation; fingers dark brown to black (Fig. 22). Carapace dark FIG. 24

Hormurus macrochela n. spec., carapace and mesosomal tergites, illustrating ornamentation and macrosculpture of cuticle (A, B), with detailed view of carapace (C, D) and tergite V (E, F), dorsal aspect. (A, C, E) Paratype male (QM-S59206). (B, D, F) Paratype female (QM-S59206). Scale, 3 mm (A, B), 1.5 mm (C-F).

reddish brown to black. Pedipalps dark reddish brown to black; carinae and fingers black. Legs pale brown. Tergites brown, paler than carapace. Coxapophyses, sternum, genital operculum, pectines and sternites orange to pale brown. Metasoma dark reddish brown to black. Telson orange; aculeus reddish-black.

Cuticle: Non-granular surfaces of carapace, pedipalps and legs, mesosoma, and metasoma finely punctate.

Carapace: Anterior margin with shallow median notch (Fig. 24A). Anterior furcated sutures and sulci distinct. Median ocular tubercle situated anteromedially, slightly raised, small, occupying about 1/6-1/7 of carapace width; superciliary carinae present, smooth; median ocelli present, at least twice the size of lateral ocelli, separated by at least half the diameter of a median ocellus. Three pairs of lateral ocelli, equal in size, equidistant and adjacent to one another. Postocular carapace margin aspinose. Surfaces finely granular, at least sparsely so, except anteromedially, with frontal lobes smooth and fine granulation restricted to surfaces adjacent to anterior furcated and median longitudinal sulci (Fig. 24C).

Chelicerae: Median and basal teeth of fixed finger fused into a bicusp. Dorsal margin of movable finger with four teeth (one subdistal and one basal); dorsal distal tooth smaller than ventral distal tooth; ventral margin smooth.

Pedipalps: Segments very long and slender (Figs 22, 23A, C, 25B-E, G-J, L-O, 26A), with femur length approximately 1.5 times carapace length (Tab. 3). Chela almost asetose. Chela fingers: Dentate margins of fixed and movable fingers linear (without lobe and notch) distally, with two rows of primary denticles, these rows fused to each other basally; larger primary denticles located at regular intervals in each row, accessory denticles absent. Fixed finger: Suprabasal lobe well developed, conical; suprabasal notch distinct and deep (Fig. 26A). Movable finger: Basal lobe absent or reduced to a few small spiniform granules; suprabasal lobe well developed, wider than high, gently rounded dorsally and lacking a sharp conical tooth, not overlapping fixed finger; suprabasal lobe and corresponding suprabasal notch on fixed finger contiguous, no proximal gap or at most a reduced gap evident when fingers closed. Pedipalp carinae: Femur (Fig. 25L-O): Dorsoexternal carina costate, usually more distinct in proximal half; dorsointernal carina distinct, more strongly developed than dorsoexternal carina; internomedian dorsal and internomedian ventral carinae obsolete, without spiniform granules; ventromedian carina obsolete; ventrointernal carina distinct. Patella (Fig. 25G-J): Prolateral process strongly developed, forming a prominent median spine; internodorsal and dorsomedian carinae distinct; dorsoexternal carina obsolete; externomedian carina granular; ventroexternal carina distinct, granular. Chela manus (Fig. 25B-E): Dorsal secondary carina obsolete; digital carina distinct, granular, more strongly developed than external secondary carina; external secondary carina obsolete; ventroexternal carina granular to crenulate; ventromedian carina obsolete;

FIG. 25

Hormurus macrochela n. spec., pedipalp chela (A-E), patella (F-J), femur and trochanter (K-O), dorsal (A, B, F, G, K, L), retrolateral (C, H, M), ventral (D, I, N) and prolateral (E, J, O) aspect, illustrating trichobothrial pattern. (A, F, K) Paratype female (QM-S59206). (B-E, G-J, L-O) Holotype male (QM-S59212). Scale, 3 mm.

FIG. 26

Hormurus macrochela n. spec., pedipalp chela, retrolateral aspect, illustrating dentate margin of chela fingers. (A) Holotype male (QM-S59212). (B) Paratype female (QM-S59206). Scale, 2 mm.

ventrointernal carina distinct, costate-granular; internomedian carina distinct, granular, more strongly developed than ventrointernal carina. Pedipalp surface macrosculpture: Femur (Fig. 25L-O): Dorsal intercarinal surface densely granular except distally; pro- and retrolateral intercarinal surfaces at least sparsely granular; ventral intercarinal surface granular, distal extremity smooth. Patella (Fig. 25G-J): Dorsal, retrolateral and ventral intercarinal surfaces granular or at least comprising a reticulated network of granules; prolateral intercarinal surface at least sparsely granular in proximal half, usually less so in distal half. Chela (Fig. 25B-E): Dorsal and retrolateral intercarinal surfaces of manus densely granular; prolateral and ventral intercarinal surfaces at least sparsely granular. Chela fingers granular, at least sparsely so in proximal half; db, dsb and dst trichobothria of fixed finger each situated in a smooth depression, surfaces around depressions granular (at least in proximal part of finger). Trichobothria: Pedipalps orthobothriotaxic, accessory trichobothria absent (Fig. 25B-E, G-J, L-O).

TABLE 3. Hormurus macrochela n. sp., measurements (in mm) of adult males and females.

Holotype Paratype Paratype Paratype

Sex Ƌ Ƌ Ƌ ♀ ♀ ♀

Repository QM- QM- MHNG QM- QM- MHNG S5921 S59206 S59206 S17042

Locality Palm Palm Magnetic Palm Palm Magnetic Island Island Island Island Island Island

Total length 66.0 61.0 48.0 70.0 64.0 55.0 Carapace, length 10.3 10.0 7.8 10.5 10.9 9.0 Carapace, anterior width 6.5 6.5 4.9 6.4 7.1 5.6 Carapace, posterior width 11.1 10.5 8.2 11.3 12.5 9.6 Chela, length 30.0 27.5 18.9 23.6 26.2 20.0 Chela manus, width 6.2 5.7 4.3 7.5 8.1 6.5 Chela manus, heigth 3.4 3.5 2.6 4.4 4.6 3.4 Chela movable finger, length 13.4 11.8 8.7 11.9 12.8 9.9 Patella, length 15.9 14.0 10.3 11.2 12.3 9.8 Patella, width 5.0 5.0 3.7 5.1 5.5 4.4 Femur, length 17.9 16.3 11.5 11.6 13.3 10.5 Femur, width 4.8 4.5 3.4 4.5 4.8 3.9 Metasomal segment I, length 3.9 3.6 2.5 3.4 4.2 3.0 Metasomal segment I, width 2.6 2.6 1.7 2.5 2.7 2.2 Metasomal segment V, length 6.4 5.8 4.8 5.7 5.7 4.6 Metasomal segment V, width 1.5 1.6 1.4 1.6 1.8 1.5 Metasomal segment V, height 1.8 1.9 1.5 1.8 2 1.6 Telson vesicle, width 1.6 1.6 1.4 1.7 1.7 1.5 Telson vesicle, height 2.0 2.1 1.5 1.8 2.1 1.8

Patella: d 2 situated distal to patellar process; five eb trichobothria arranged in two groups, eb 1 and eb 2-5 or eb 1 / eb 4-5 and eb 2-3; two esb trichobothria; two em trichobothria; one est trichobothrium; three et trichobothria; three V trichobothria. Chela manus with Dt situated in proximal third; Eb 3 situated close to Eb; Esb situated distal to Eb series and close to Est; Est situated at or near midpoint; four V trichobothria, with V 3 and V 4 separated. Chela fixed finger with db situated on dorsal surface; eb, esb, est and et equidistant (distance esb-est similar to distance eb-esb); eb situated at base of finger, behind point of articulation between fixed and movable fingers, aligned with esb-et axis; esb situated proximally on fixed finger, aligned with est-et axis; two i trichobothria.

1-2

Coxosternum: Leg III coxae without swelling or bulge anterodistally. Sternum equilateral pentagonal (Fig. 27A); anterior width slightly greater than posterior width; length less than or equal to posterior width.

Legs: Femora I-IV each with ventral surfaces bicarinate (proventral carinae less developed than retroventral carinae); IV with ventral carinae vestigial (only expressed distally) and indistinct, reduced to scattered granules. Retroventral margins of tibiae I and II without setiform macrosetae. Pro- and retroventral margins of basitarsi I-IV each with 4 setiform macrosetae. Telotarsi I-IV: Pro- and retroventral margins each with 4/4, 4/4, 5/5, and 5/5 setiform macrosetae, respectively (Fig. 28D, E); ventromedian row of spinules reduced to few spinules basally, terminal ventromedian spinules absent; dorsomedian lobe pronounced; laterodistal lobes truncate; ungues curved, shorter than telotarsus.

FIG. 27

Hormurus macrochela n. spec., coxae of legs II-IV, sternum, genital operculum and pectines, ventral aspect. (A) Holotype male (QM-S59212). (B) Paratype female (QM-S59206). Scale, 2 mm.

FIG. 28

Hormurus macrochela n. spec., metasoma and telson, lateral aspect (A, B) and ventral (C) aspect, and left tarsus IV, retrolateral (D) and ventral (E) aspect. (A) Paratype female (QM-S59206). (B-E) Holotype male (QM-S59212). Abbreviation: ps (proximal spinules). Scale, 3 mm (A, B), 1 mm (D, E).

FIG. 29

Hormurus macrochela n. spec., holotype male (QM-S59212) (A-C), male from Magnetic Island (MHN) (D), left hemispermatophore. (A) Dorsal aspect. (B-D) Detail of capsular region, ental (B, D) and ventral (C) aspect. Scale, 1 mm.

Genital operculum: Composed of two subtriangular sclerites (Fig. 27A).

Pectines: Pectines slightly elongated, distal edge reaching but not surpassing distal edge of leg IV coxa (Fig. 27A); fulcra and three marginal lamellae present. Pectinal tooth count 7-9; teeth long and straight, entirely covered with sensory papillae.

Mesosoma : Posterior margins of pre-tergites I-VII smooth (Fig. 24A, E). Posterior margins of post-tergites I-VII sublinear, without distinct prominence (Fig. 24A, E); I-VI each with lateral transverse sulci; intercarinal surfaces of I-VII finely granular, at least in posterior half, more sparsely granular medially on I-III; intercarinal surfaces of III-VII uneven, with a distinct reticulated network of ridges and dimples. Respiratory stigmata (spiracles) of sternites IV-VI, short, less than one third sternite width and crescent-shaped, with distinct curve; sternite VII acarinate.

Metasoma: Length similar to that of ♀ (Tab. 3), not flattened laterally (Fig. 28B, C), intercarinal surfaces sparsely granular. Segments I-IV each with median sulcus distinct and deep; segment V with sulcus shallow, especially in posterior half; dorso-submedian carinae obsolete; dorsolateral, ventrolateral and ventro-submedian carinae distinct on at least some segments. Segment I: Width less than or equal to height (Tab. 3); dorsomedian posterior spiniform granules weakly developed or absent; posterior spiniform granules of dorso-submedian carinae weakly developed or absent, not noticeably larger than preceding granules; lateral median carinae distinct; ventro-

FIG. 30

Hormurus macrochela n. spec., male from Magnetic Island (MHN), left hemispermatophore, detail of capsular region. (A) Rotated approximatively 30º clockwise from ental aspect. (B) Rotated approximatively 30º counter-clockwise from ental aspect. (C) Ental aspect. (D) Ventral aspect. Abbreviation: ah (accessory hook). Scale, 1 mm.

FIG. 31

Known localities of Hormurus macrochela n. spec. in northern Queensland, Australia, with topography indicated.

submedian carinae each with one or two spiniform granules subposteriorly, without spiniform granules medially or posteriorly. Segment II: Dorsomedian posterior spiniform granules weakly developed or absent; posterior spiniform granules of dorso-submedian carinae weakly developed or absent, not noticeably larger than preceding granules; ventrolateral carinae without spiniform granules; ventro-submedian carinae each with one or two small spiniform granules medially, one or two subposteriorly, and none posteriorly. Segments III and IV: Posterior spiniform granules of dorso-submedian carinae weakly developed or absent, not noticeably larger than preceding granules; ventrolateral and ventro-submedian carinae weakly developed, sparsely granular, without spiniform granules. Segment V: Dorsal intercarinal surface sparsely granular; dorsolateral carinae obsolete; ventrolateral carinae weakly developed, posterior half comprising few spiniform granules becoming larger posteriorly; ventromedian carina weakly developed, comprising a sparse row of granules in anterior half, indistinct posteriorly; anal arch crenulate, comprising small denticles.

Telson: As long as or slightly longer than metasomal segment V (Fig. 28B); vesicle surfaces smooth.

Hemispermatophore (Figs 29-30): Distal lamina gently curved, approximately same length as basal part; distal crest absent; single laminar hook situated in basal third; basal extrusion absent; transverse ridge distinct, approximately aligned with base of laminar hook, merging with ental edge distal to laminar hook. Capsular lamella thin, folded proximally and unfolded distally to a flattened extremity (tip and base approximately the same width); longitudinal carina on dorsal surface absent; accessory hook and accessory lobe absent; lamellar tip situated proximal to base of laminar hook, distal to tip of distal lobe. Distal lobe well developed, not hook-like, without accessory carina or crest, and with one or two large proximad-oriented accessory hooks on ental surface (Figs 29B-D, 30). Basal lobe well developed, spoon-shaped, merging with ental basal process; ectal edge without accessory fold, forming 135-150º angle with lamella; ental edge without accessory fold toward ectal part, forming 90º angle with lamella.

DESCRIPTION OF ADULT FEMALE: As for the Ƌ except as follows.

Pedipalps: All segments shorter and more robust than in male (Figs 23B, D, 25A, F, K, 26B). Dentate margins of chela fingers linear or nearly so, i.e. without pronounced lobe and notch (Fig. 26B).

Genital operculum: Oval to semi-oval, wider than long, approximately same width as sternum (Fig. 27B); opercular sclerites partly fused, median suture distinct; posterior notch present, at least weakly developed.

Pectines: Short, distal edge not reaching distal edge of leg IV coxa (Fig. 27B). Pectinal tooth count 5-7; teeth short and curved, sensory papillae restricted to distal part.

Mesosoma: Intercarinal surfaces of post-tergites I-III smooth medially, granular laterally (Fig. 24B, F); intercarinal surfaces of IV-VI smooth or nearly so; intercarinal surfaces of VII granular posteriorly.

INTRASPECIFIC VARIATION: The pedipalps of larger males are proportionally longer than those of smaller males (positive allometry) ( Monod , Harvey & Prendini , in preparation). Pectinal tooth counts vary from seven to nine in males and from five to seven in females. The distal lobe of the hemispermatophore usually bears one large hook on the ental edge, but two were observed in some specimens (Fig. 29A-C). This hook may be much more elongated, with a small posteriad-oriented excrescence (Fig. 29D) in some specimens.

REMARKS: Koch (1977) mentioned the large size of the pedipalp chela of specimens examined from Palm Island, but considered them conspecific with L. waigiensis. Volschenk et al. (2001) identified a specimen of this species from Magnetic Island as L. waigiensis based on the taxonomy current at the time.

DISTRIBUTION AND ECOLOGY: Hormurus macrochela is recorded from vine forests on three islands off the eastern coast of northern Queensland, between Ingham and Townsville (Fig. 31). Specimens were collected from narrow rock crevices and between stones near creeks in vine forest and rainforest. The habitat and habitus are consistent with the lithophilous ecomorphotype ( Prendini, 2001 ).

CONSERVATION STATUS: The known populations of H. macrochela are situated on islands off the coast of northern Queensland, most of which are protected and part of two national parks (Orpheus Island National Park, Magnetic Island National Park). Therefore this species is not threatened by habitat destruction.