Limbodessus leysi Watts &amp; Humphreys 2006
Creators: name: Michat, Mariano C.
name: Alarie, Yves
name: Watts, Chris H. S.
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Dytiscidae
Limbodessus
Limbodessus leysi

description: <i>Limbodessus leysi</i> Watts &amp; Humphreys, 2006 (Figs 89 –106) <b>Source of material.</b> One specimen of instar I and three of instar III were used for the description (Table 1). Larvae were collected in association with adults at the following localities: <b>Australia, Carey palaeovalley</b>, Mt Morgan calcrete, Mt Weld Station, PB 1, BES 11816, 28.73439S, 122.14942E, 30–IX–2004, coll. W. F. Humphreys and S. J. B. Cooper; Mt Morgan calcrete, Mt Weld Station, PB 4, BES 10581, 28.72177S, 122.1569E, 30–IX–2004, coll. W. F. Humphreys and S. J. B. Cooper. <b>Diagnosis (instar III).</b> Medium-sized species (HL 0.55–1.15 mm); head (Fig. 103) subpentagonal; nasale subtriangular; half-circle of dense spinulae on lateroventral margins of nasale present; hole-like structure on ventrodistal surface of nasale absent; lateral margins of nasale inflated in dorsal view; lateral branches of nasale minute; slender spinulae anterior to seta FR13 scarce (20 or less); occipital foramen well developed (HW/OCW less than 1.90); occipital suture present; lateral margins of parietal straight; secondary spiniform setae on lateral margins of parietal scarce; seta AN2 present; distal half of MN broad; setae LA3, LA4, LA5 and LA8 hair-like; secondary setae on U absent (Fig. 106). <b>Instar I</b> (Figs 89 –102). Head (Figs 89–97). Cephalic capsule strongly elongate (HL/HW more than 1.55); seta PA3 inserted far from setae PA1 and PA2; A3 more than 2.80 times longer than A1; A3 more than 2.25 times longer than A2; MP2 1.55–1.85 times longer than MP1; MP2 1.95–2.65 times longer than MP3; LP2 1.40–2.00 times longer than LP1. Legs (Figs 98–99). L3 less than 2.85 times longer than HW. Abdomen (Figs 100–102). U more than 3.75 times longer than LAS; U more than 2.45 times longer than HW; U1 1.10–1.40 times longer than U2. Chaetotaxy. Frontoclypeus with 12 lamellae clypeales; additional setae on U absent. Measurements and ratios that characterize the body shape are shown in Table 2. <b>Instar II.</b> Not available. <b>Instar III</b> (Figs 103–106). Head (Fig. 103). A3 less than 2.25 times longer than A1; A3 less than 1.45 times longer than A2; MN less than 4.85 times longer than broad; MP less than 1.75 times longer than labial palpus; MP2 2.10–3.10 times longer than MP3; LP2 more than 0.65 times as long as LP1. Legs (Figs 104–105). L3 2.25–2.85 times longer than HW. Abdomen (Fig. 106). U 2.40–3.10 times longer than LAS; U 1.55–2.25 times longer than HW; U1 0.70–1.40 times as long as U2. Chaetotaxy. Anteroventral margin of nasale with 48 lamellae clypeales distributed in 2 rows; pro- and mesoCO without anterior secondary setae; pro-, meso- and metaCO without posterior secondary setae; proCO with less than 11 secondary setae; metaCO with less than 20 secondary setae; anterodorsal secondary setae on pro- and metaFE present; metaFE with less than 12 anteroventral secondary setae; posterodorsal secondary setae on meso- and metaFE absent; metaFE with 9–27 secondary setae; anterodorsal secondary setae on proTI absent; anteroventral and posterodorsal secondary setae on proTI present; mesoTI with less than 4 anteroventral secondary setae; metaTI with less than 9 anteroventral secondary setae; metaTI with less posterodorsal secondary setae on meso- and metaTA present; proTA with 1–7 secondary setae; mesoTA with less than 7 secondary setae; metaTA with less than 16 secondary setae; secondary setae on U absent. Measurements and ratios that characterize the body shape are shown in Table 10. Secondary leg setation detailed in Table 18. <b>Remarks.</b> <i>Limbodessus leysi</i> belongs to the group of species characterized by the absence of secondary setae on the urogomphus (<i>L. challaensis</i>, <i>L. exilis</i>, <i>L. fridaywellensis</i>, <i>L. hillviewensis</i>, <i>L. hinkleri</i>, <i>L. masonensis</i>, <i>L. millbilliensis</i>, <i>L. morgani</i>, <i>L. ordinarius</i>, <i>L. pulpa</i>, <i>L. raeae</i>, <i>L. windarraensis</i>, <i>L. yuinmeryensis</i>) (Fig. 106). Compared to other members of this group, the larvae of <i>L. leysi</i> can readily be distinguished by the following combinations of characters: lateral margins of the nasale inflated in dorsal view, bearing a half-circle of dense spinulae (Figs 90, 103), and primary seta AN2 present.
description: Published as part of <i>Michat, Mariano C., Alarie, Yves &amp; Watts, Chris H. S., 2012, 3584, pp. 1-110 in Zootaxa 3584 (1)</i> on pages 50-54, DOI: 10.11646/zootaxa.3584.1.1
description: {"references": ["Watts, C. H. S. &amp; Humphreys, W. F. (2006) Twenty-six new Dytiscidae (Coleoptera) of the genera Limbodessus Guignot and Nirripirti Watts &amp; Humphreys, from underground waters in Australia. Transactions of the Royal Society of South Australia, 130, 123 - 185."]}