Stigmops odontotergina, Lillemets & Wilson, 2002

Lillemets, B. & Wilson, G., 2002, Armadillidae (Crustacea: Isopoda) from Lord Howe Island: New Taxa and Biogeography, Records of the Australian Museum 54, pp. 71-98 : 79

Stigmops odontotergina n.sp.

Figs. 7–10

Type material. HOLOTYPE Ƌ, P59976, 4.5 × 2.5 mm, LHI386 . PARATYPES: P59980, ♀, 5.4 × 2.9 mm, LHI392 ; P59996, Ƌ on 5 SEM stubs, LHI392 ; P59981, Ƌ, 1 SEM stub, LHI392 ; P59979, ♀, 2 SEM stubs, LHI358 ; P59994, 15 inds, LHI392 ; P59995, Ƌ, SEM stub, LHI178 095 ; P59977, 2 specimens, LHI 178 095 ; P59982, 3 specimens, LHI 178 095 ; P59987, 1 specimen, LHI356 ; P59988, 2 specimens, LHI357 ; P59978, 1 specimen, LHI357 ; P59989, 7 specimens, LHI358 ; P59990, 2 specimens, LHI365 ; P59991, 1 specimen, LHI366 ; P59992, 1 specimen, LHI382 ; P59993, 3 specimens, LHI386 ; P59985, 1 specimen, 11.vii.79, LHI610 ; P59986, 2 specimens, 11.vii.79, LHI613 .

Type locality. “Little Slope”, west side of Mount Gower , Lord Howe Island, New South Wales, Australia, 31°35'S 159°04.5'E, from pitfall traps in leaf litter, vegetation Howea forsterana forest, K&M 22.xi.1978 & 20.xii.1978 .

Additional material. P59983, 1 specimen, LHI544 ; P59984, 1 specimen, LHI544 ; P34858, 7 inds, LHI 390 .

Diagnosis. Cephalon frontal lamina indented, midline slightly curved; vertex with four ridge-like tubercles, middle two near longitudinal, lateral two transverse. Pereon dorsal ornamentation pereonite 1 with one large anterior longitudinal ridge-like midline tubercle, tergites 1–7 each with one pair of longitudinal, ridge-like midline tubercles near posterior margin, and two pairs of smaller longitudinal ridge-like tubercles lateral to midline. Pleonites 2–5 dorsal surface with one midline tubercle each, pleonites 2 and 5 tubercles similar size, pleonite 3 tubercle larger, pleonite 4 tubercle smaller; pleonite 3 with two small lateral tubercles. Penes with row of 5 medial ventral spines. Uropod protopod length 1.1 width; endopod 2.5 exopod length.

Description. Colour uniform light brown in alcohol. Original photos show darker uniform brown. Body ( Fig. 7A,E,G) strongly convex with subhorizontal epimera. Dorsal cuticle of entire animal and frons with complex pattern of scales and pits. Cephalon ( Fig. 7B,D) frontal lamina raised off vertex, indented, midline slightly curved, lateral margins triangular. Dorsal ornamentation four ridgelike tubercles, middle two near longitudinal, lateral two transverse along posterior margin, one pair of low round tubercles on midline near anterior margin, ridge above eyes. Head square, width 0.5 pereon width, width 2.0 length. Eyes with 6–10 ocelli in adults. Pereon ( Fig. 7A–C,E,G) epimera 1 anterior margin narrowly rounded, extending anterior to eye, dorsal surface concave, lateral margin simple, posterior margin broadly rounded, ventral surface with longitudinal ridge closer to tergite junction than to lateral margin extending from anterior margin, ending in tooth-like endolobe anterior to posterior margin, endolobe not visible dorsally; epimera 2 anterior margin rectangular, posterior margin rounded, ventral surface with large tooth-like endolobe extending posteriorly from anterior margin; epimera 3–7 anterior margin rectangular, increasingly rounded; epimera 3–4 posterior margin rounded, that of epimera 5–7 rectangular; epimera 3–7 endolobes absent; epimera 1–7 decreasingly angled towards posterior. Tergite 1–7 posterior margins slightly curved; tergite 1 length 0.2 pereon length. Dorsal ornamentation pereonite 1 with one large longitudinal ridge-like midline tubercle near anterior margin, one rounded tubercle on each side behind eyes; tergites 1–7 each with one pair of longitudinal, ridge-like midline tubercles near posterior margin increasing in size posteriorly, two pairs of smaller lateral longitudinal ridgelike tubercles, decreasing in size posteriorly; low, rounded tubercles scattered above epimera tergite junction and on epimera. Pleon ( Fig. 7E) pleura laterally truncate; pleonites 1–5 posterior margins rounded; pleonites 2–5 dorsal surface with one midline tubercle each, pleonites 2 and 5 tubercles similar size, pleonite 3 tubercle larger, pleonite 4 tubercle smaller; pleonite 3 with two small lateral tubercles. Pleotelson ( Fig. 7H) sides slightly constricted, proximally wider than distally; length 0.75 width; posterior margin straight; dorsal surface with two proximal and two distal smaller rounded tubercles. Antenna ( Fig. 7B) short, thick, reaching epimera 1 posterior margin, length 0.85 article 5, flagellar article length proportions 1:3; all segments setose, flagellum more densely including longer apical setae. Mandibles ( Fig. 10A,B,E,F). Right mandible setose lobe with shorter, thicker, less setae than left mandible, concentrated at lacinia mobilis base; simple setae only, robust penicils not present. Penes ( Fig. 9A) lanceolate with row of 5 medial ventral spines; proximal bilobed lamellar process rectangular, covering 0.33 penes length. Male pleopod ( Fig. 8B,C) 1 exopod rounded, pseudotrachea along proximal lateral margin width 0.5 exopod width, length 0.4 exopod length; exopod length 0.25 endopod length. Pleopod 2 exopod proximal wide portion length 0.3 exopod length, exopod width 0.6 exopod length, pseudotrachea along proximal lateral margin width 0.45 exopod width, length 0.2 exopod length, one lateral thick seta 0.25 exopod length from apex; endopod proximal article length 0.2 endopod length; exopod length 0.7 endopod length. Pleopods 3–5 exopods triangular with fine apical setae, ventral scales, dorsal ridge along lateral margin, ventral ridge along proximal margin, pleopod 5 exopod with three long apical setae and many short, fine setae along apex and medial margin. Uropod ( Fig. 7H) protopod subtriangular; length 1.1 width; median margin straight portion length 0.35 lateral margin length; dorsally visible distal portion short with rounded apex; length (along inner margin of dorsally visible portion) equal to width (at point of exopod insertion); protopod dorsally visible portion length 2.5 exopod length; endopod 2.5 exopod length.