Ancyronyx toraja Freitag & Kodada, 2017

Freitag, Hendrik & Kodada, Ján, 2017, Larvae of Ancyronyx Erichson, 1847 (Insecta: Coleoptera: Elmidae) from Sulawesi, using DNA sequences for the assignment of the larval stages, Zootaxa 4299 (1), pp. 121-130 : 128

Ancyronyx toraja Freitag & Kodada, 2017

( Figs 2 E; 5A–D)

Material examined. 24LL ( CFM): “ INDONESIA: S Sulawesi, 17.5km NNW Rantepao 1510m asl., mount. riv. “Salu Maiting”, pine forest/paddy fields, run; submerged wood, c . 02°49′21′′ S 119° 51′17′′E 31 Dec.1997 leg. Freitag (Sul 4f)”; 6LL ( NMW, CKB [SEM], CFM [FR133]): “ INDONESIA: S Sulawesi, 17.5km NNW Rantepao 1570m asl ., small mount. river “Salu Malarak”, pine forest, run/riffle; submerged wood, c. 02°48′51′′ S 119° 51′21′′E 31 Dec.1997 leg. Freitag (Sul7f)”.

Differential diagnosis (based on presumably fifth and sixth instar, HW: 0.32–0.38 mm). In most characters very similar to Ancyronyx tobada , except for the following: generally dark brown dorsally; paler brown areas limited to lateral portion of head, small areas at anterior and anterolateral margins of pronotum and apex of terminal abdominal segment. Entire ventral side pale. Dorsal tubercles moderately elevated, lateral protuberances distinctly protruding. Head distinctly tapering anteriad, widest at posterior 0.2. Abdominal segments distinctly, protuberantly elevated in posterior portions; posterior abdominal segments I–VIII with four erected setae; segment IX with six of such setae dorsally ( Fig. 5 D, these setae are less distinct in the six larval instar); posterolateral protuberances with prominent tubercles and two distinct, moderately long setae ( Figs 5 B, C); terminal segment IX ( Figs 5 C, D) moderately long, ca. 2.0 times as long as wide; basomedian portion tuberculate; apex distinctly emarginated.

Figures

FIGURE 2. Habitus of Ancyronyx larvae from Sulawesi, A: A. schoedli (body length 2.90 mm), B: A. skalei (body length 2.65 mm), C: A. tobada (body length 2.95 mm), D: A. longiparamerus (body length 2.95 mm), E: A. toraja (body length 3.30 mm), F: A. henningi (body length 2.35 mm).

FIGURE 5. Ancyronyx toraja larva, dorsal (SEM photographs), A: head and pronotum; B: details of abdominal segments I – IV with tubercles, lateral abdominal projections, and setae; C: abdominal segment IX; D: detail of abdominal segment IX with 3 pairs of erected setae.