Sundacypha petiolata
Creators: name: Orr, Albert G. W.
name: Dow, Rory A.
name: Steinhoff, Philip O. M.
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Odonata
Chlorocyphidae
Sundacypha
Sundacypha petiolata

description: Sundacypha petiolata (Selys)
(Figs 4c, 5c, 7c, 8c, 9c, 11b, 12c, g, 14c, d, 15c, d, 16b, f, 17b, 18c)
Material examined. MALAYSIA, 1 ♂ F, 1 ♀ F (RMNH.5008329, RMNH.5008330), stream in kerangas near Camp C, Planted Forest Project, Bintulu Division, Sarawak, 2.7171N, 113.3463E, 26 iii 2014 (RMNH.5008329), 27 iii 2014 (RMNH.5008330), leg. S.G. Butler.
Habitus: similar to H. biseriata but obviously smaller (Fig. 4c). Significantly paler mottling on head and body in specimens examined which have predominantly pale yellowish ground colour. Both head and antennae relatively longer, especially the latter; prothorax lower in profile with anterior tubercles much reduced; prothorax legs proportionally slightly longer, caudal spikes proportionally longer but thinner and more evenly tapered to a point from base.
Head: in dorsal view as illustrated (Fig. 5c), similar to H. biseriata but slightly more elongate and antennae proportionally longer (1.63 times maximum head width versus 1.52 in H. biseriata) and markings weaker, with subtle differences but tip of pedicel with similar dark coloration; scape with longer and mainly longer straighter setae but a few recurved short setae so that wet specimens may appear sparsely warty. Labrum as in H. biseriata but more strongly curved, accommodating long mandibular incisor lobes; ‘moustache’ with 9–10 strong setae. Ventrally, genae bear a cluster of subocular spines shorter and less numerous than in H. biseriata, all main spines except first appear rounded in ventral view (Fig. 7c right) but these are upturned and acuminate as seen in lateral view (Fig. 7c left). Head, especially seen in lateral view longer and shallower than previous two species, with other differences as shown (Fig. 7c). Mask very long and thin, articulation resting between posterior part of coxae of mesothorax (Fig. 8c); prementum narrow basally, gradually flared anteriorly with margins of anterior half straight; lateral margins with sparse fine setae on distal 2/3 rd (Fig. 9c) seated in distinctly raised sockets (Fig. 11b); anterior median lobe as in H. biseriata but only slightly convex; median cleft very short with tinted area marking point of closure (Fig. 11b); lobe of labial palp as in previous species, but with both palpal lobe and movable hook relatively slightly longer relative to anterior breadth of prementum as indicated (Figs 10a, b,c, 11b). Maxillae as in previous species (Fig. 12c), but with basal pair of secondary denticles on distal tooth well separated as in A. fenestrella and all relatively shorter and lighter than in that species (Fig. 12g). Mandibles (Figs 14c, d, 15c, d)—both left and right with five distinct teeth on incisor visible in internal view, dorsal one small; right with small supplementary tooth basal to strong ventral tooth; right molar crest a low elongate shallow ridge without obvious dentition and lightly sclerotised (Figs 14c, 15d); left incisor (Figs 14d, 15c) with five well developed teeth, the strongest ventrally; molar crest a strong flat dorso-ventral blade with eight minute denticles along a nearly straight distal margin, with end denticles markedly heavier and longer, especially ventrally (Figs 14d, 15c). A strong outer basal seta on both mandibles as in other three species.
Thorax: anterior tubercles on prothorax less developed and more centrally placed than in other two species (Fig. 5c, arrowed), and anterior and posterior flanges defining saddle lower. Otherwise similar. Marking (not illustrated on body) lightly mottled but always with broad pale band between two anterior tubercles on prothorax. Wing sheaths slightly spatulate, not completely obscuring abdomen at sides, forewing reaching to near end of S5, hindwing to 2/3 along S6 (Fig. 4c). Legs long and thin, metafemur reaching base of S8, clearly proportionally longer than in H. biseriata which they resemble in all other respects including presence of two rows of pectinate setae on the venter of the tarsus. Unlike the previous two species the tibiae have no markings.
Abdomen: squat, mainly mottled brown with well-defined pale narrow middorsal stripe (not figured). Margins of S3–7 distinctly crimped forming shallow lateral keels; venter of S6–8 with irregular sparse row of tiny submarginal spines; ventrolateral margin of S9 with 5–7 strong, curved spines and scattering of tiny marginal and submarginal spines along venter (Figs 16b, 17b); S10 with 3–6 strong ventrolateral spines (Figs 16b, 17b) and cluster of smaller spines on venter and ventrally on tergite (Fig. 16f); hind-margin S10 with 3–4 strong rearward pointing ventrolateral spines (Figs 16b, f, 17b) and small spines along all of hind margin, being sparsest ventrally. Male gonapophyses (Fig. 17b) short and conical, well separated, arising near posterior margin S9 and just reaching margin. Outer female gonapophyses (Figs 16b, f) arising from base of S9 and extending well beyond hind margin of S10 to about level of epiproct tip (Fig. 16f), ventral margin with series of sparse heavy spines to about level of hind margin S10, thence continuing almost directly backward to a sharp point about level with epiproct tip (Fig. 16f); inner apophyses smooth, curved smoothly and strongly upward to a rounded point extending well beyond outer apophyses and epiproct. Epiproct, short, subconical, not obviously different from other species studied. Caudal spikes about 65% body length, of medium breadth at their base and tapered almost uniformly to a point (Fig. 18c); bearing numerous backward facing strong sharp curved spines, heavy setae, and also long fine setae too matted to assess accurately, but apparently dense.
Measurements (mm): body length, 9.9; lateral caudal spikes 6.4; head width 2.6; prementum 2.65; mandibles 0.75; palpal lobe (to tip of dorsal branch) 0.58; movable hook 0.52 maxillary palp 0.57; galeolacinia to distal tooth 1.2; antennae 1.70, 0.74, 0.80, 0.49, 0.24, 0.15, 0.11 (total 4.23).
Remarks
This species exhibits several distinctive characters when compared with other genera studied: the mask is elongate, as is the head, although the latter is not very obvious. The antennae are long in proportion to head width. The anterior tubercles on the prothorax are reduced and the caudal spikes are very long thin, spiny and distinctively tapered. The posterior segments of the abdomen bear considerably more small spines on the venter and ventral margins than in the other species and the specimens examined were much paler than other genera, but it is unclear if this is a reliable character. Only one other species S. striata is known from the genus, closely related to S. petiolata. It seems likely that its larvae when discovered will be very similar, but it is possible differences occur especially in the shape of the prementum, to judge from known variation in other genera.
description: Published as part of Orr, Albert G. W., Dow, Rory A. & Steinhoff, Philip O. M., 2024, Descriptions of larvae of four mainly DNA barcode-matched species of chlorocyphids from south-east Asia (Odonata: Chlorocyphidae) with notes on the generic and species level larval identification of Oriental region members of the family., pp. 301-337 in Zootaxa 5486 (3) on pages 316-317, DOI: 10.11646/zootaxa.5486.3.1, http://zenodo.org/record/13210005