Monodontium mutabile Kulczynski, 1908

Raven, Robert J., 2008, A Revision Of The Mygalomorph Spider Genus Monodontium Kulczynski (Barychelidae: Araneae), Raffles Bulletin of Zoology 56 (1), pp. 29-44 : 32-34

Monodontium mutabile Kulczynski, 1908

( Figs. 1 , 2A–E ; Table 1)

Monodontium mutabile Kulczynski 1908: 446 ; Roewer, 1942: 224.

Monodontium mutabile typica Kulczynski 1908: 450 ; Roewer, 1942: 224.

Monodontium mutabile minor Kulczynski 1908: 450 ; Roewer, 1942: 224; Bonnet, 1957: 2984 (emended to M. m. minus by Platnick, 2001). New synonymy.

Monodontium mutabile oculatissimum Kulczynski 1908: 450 ; Roewer, 1942: 224; Bonnet, 1957: 2984. New synonymy.

Monodontium mutabile oculatior Kulczynski 1908: 450 ; Roewer, 1942: 224; Bonnet, 1957: 2984. New synonymy.

Material examined. – Monodontium mutabile : holotype (“typus”) female, 2 juv. paratypes, Erima (Astrolabe Bay) J.Z.P.A.N. 46/51 ( NMNH) .

Monodontium m. minus: syntypes, 1 penultimate male, 2 juv., “N.G. sept-or: Sattelberg [6º29'S 147º46'E], III.1899, L. Biro / 46/51” ( NMNH) .

Monodontium mutabile oculatissimum : “ 1 juv. syntypi N.G. sept- or: Sattelberg [6 ° 29'S 147 ° 46'E], L. Biro / 46/51. U.” ( NMNH) .

Monodontium m. oculatior: “ 4 juv. syntypi, Madang [=Friedrich- Wilhelmschafen , 5º00'S 145º30'E,] leg. L. Biro ”. Y.Z.P.A.N. 46; “1 juv syntypi Hansemannberg 23. v. leg L. Biro ” ( NMNH) .

Diagnosis. – Females differs from those of M. malkini in having the claws of legs IV with two rows of teeth and in the relatively longer eye group.

Description. – Holotype, female (NMNH): Carapace 3.48 long, 2.84 wide. Abdomen 4.00 long, 2.72 wide. Total length, 9.0.

Colour in alcohol: Carapace brown with black margins and dark brown mottling on lateral caput and interstrial ridges, chelicerae light brown, legs light brown with slightly darker annulations on tibiae and metatarsi. Abdomen with many distinct white spots, laterally pallid, venter similar with short transverse bands laterally.

Carapace: Bristles: many moderately long brown along margins and on interstrial margins; line present anteromedially; few between PME and in front of AME. Clypeus absent. Fovea straight. Striae shallow, glabrous.

Eyes: Tubercle low but distinct. Three rows; back row slightly procurved. Eye group occupies 0.34 of head-width; front width, back width, length, 31:38:25. MOQ front width, back width, length, 20:25:16. AME:ALE:PME:PLE, 10:11:7:9. Eye interspaces: AME–AME, 0.2, AME–ALE, 0.5, ALE– ALE, 1.4, PME–PME, 1.5, ALE–PLE, 0.9.

Chelicerae: Small, rounded. Narrow band of moderately long brown bristles dorsally and narrower band of shorter bristles laterally. Distally with curved stiff spines, thickest spines on edge forming a line of about 10–12 stiff spines. No modification on inner or outer faces. Outer fang smooth, inner with single medial keel. Promargin of furrow with 8 large and one smaller tooth; basomesally with a group of 10–15 granules.

Labium: 0.80 wide, 0.36 long; wider than long, with one cuspule; separated from sternum by continuous groove.

Maxillae: 1.06 long in front, 1.34 long behind, 0.64 wide; with about 17–20 cuspules along inner edge. Anterior lobe indistinct; heel broadly rounded. Lyra absent. With transverse glabrous groove on anterior face.

Sternum: 1.80 long, 1.70 wide. Rounded; uniformly setose; sigilla evident as small round shallow depressions near margin.

Legs: Scantily setose but not hirsute. Coxae not modified. Scopula: very thin and widely divided on palpal tarsi, metatarsi I, and tarsi I, II; absent elsewhere. Thorn spines and preening combs absent.

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Spines: Many thick stiff setae on prolateral tibiae and metatarsi I and II. Leg 1, me v2; leg 2, ti v1, me v3; leg 3, pa p2, ti p2, r1, v4, me p3, r2, v11; leg 4, fe d1, pa r1, ti p3, r3, v6, me p4, d1, r3, v12; palp, ti v4.

Claws: Three to five teeth in each of two rows on paired claws; leg I–III with 3 in outer, and 5 on inner rows; leg IV with 3

in both rows. Palpal claw bare. Tufts small, distinct, apically separated.

Trichobothria: In two rows on tibiae, each of 10–12 for twothirds of length; all filiform on metatarsi and tarsi in irregular rows.

Palp: Claw tufts absent.

Spermathecae: Two, each a bipartite (not divided) lobe reflexing laterally at its midpoint ( Fig. 2E ).

Spinnerets: Two, PMS not represented by tuft of hair. PLS length of basal, middle, apical, and total articles 0.68, 0.28, 0.16, 1.12, respectively; basal segment 0.34 in diameter.

Male: Unknown.

Distribution. – Madang and region near Astrolabe Bay, NE Papua New Guinea.

Remarks. – Kulczynski (1908) described only one species of Monodontium , M. mutabile . In that species, he included four varieties subsequently considered subspecies which were not recognised by Bonnet (1957) and not explicitly placed in synonymy. Of the types of those subspecies: M. m. minus, the largest is a penultimate male, the others are about onethird its size and at least three moults from maturity; all material of M. m. oculatior and M. m. oculatissimum are juvenile, even as labelled by Kulczynski (1908). All material of the subspecies were labelled as syntypes; however, the holotype of the nominate species was so labelled.

Figures

Fig. 1. Occurrence of Monodontium.

Fig. 2. Monodontium mutabile Kulczynski, holotype female, A–E: A, cephalothorax and abdomen, dorsal view; B, eyes, dorsal view; C, abdomen, ventral view; D, sternum, maxillae, labium and chelicerae; E, spermathecae. F, Monodontium tetrathela Kulczynski, spermathecae. Scale bars = 1 mm for A, C; 0.5 mm for B, D.