Duliticola Mjöberg, 1925

BOCAK, L. & MATSUDA, K., 2003, Review of the immature stages of the family Lycidae (Insecta: Coleoptera), Journal of Natural History 37 (12), pp. 1463-1507 : 1472-1474

Duliticola Mjöberg, 1925

Immature stages described in literature. Duliticola paradoxa Mjöberg (Mjöberg, 1925) , D. korinchiana Blair (Blair, 1928) , D. hoiseni Wong (Wong, 1996) .

Systematic position of Duliticola . Mjöberg (1925) considered Duliticola to be the well-characterized group of primitive lycids and wrote that ‘it would be perhaps justifiable to separate the group of ‘‘trilobite larvae’’, ... and give them the rank of a family or sub-family ... (Duliticolidae or Duliticolinae )’. But he concluded that our knowledge is too limited to justify such a step. At present, the genus is classified as ‘incertae sedis’ in Lycidae (Lawrence and Newton, 1995) . Platerodrilus Pic , earlier classified in Drilidae , is very similar to Duliticola in the adult male. These genera form a distinct group of yet unknown relationships.

Diagnosis. Body shape very characteristic (figures 20–23), ‘trilobite larva’ of many authors. Following diagnostic characters were found: fossa antennalis closed, separated from mouth-parts by pleurostoma (pleurostoma absent from other lycids); slender, longitudinal sclerite present ventrally of pleurostoma (figure 26); mala sclerotized (figure 27). Apical antennomere with several peg-like processes (figures 25, 26). Spiracles situated at margin of deep, large cavities surrounding spiracular scar in mature larvae (figure 24), additional spiracles in bottom of cavity. Meso- and metasternum with paired tubercles (figure 22). Sclerites of A1–A8 with at least one process at posterior margin (figure 23).

Description of mature female larva (spec. #1). Body wide, considerably flattened due to extensively projected lateral plates (figures 20, 22). Dark brown, heavily sclerotized, membranes restricted to intersegmental regions. Head slightly longer than wide, anterior margin projected, rounded (figure 25). Epicranium consisting of dorsal and pleural plates, membranous between plates. Complete fossa antennalis present, dorsally limited by epicranium, ventrally by sclerotized pleurostoma. Longitudinal sclerite situated ventrally of pleurostoma. Basal antennomere very short, apical antennomere with several peg-like processes ventrally and more extensive, sclerotized area dorsally (figures 25, 26). Mala sclerotized, with peg-like process (figure 27). Ventral plate with posterolateral processes (figure 26). Cervical membrane extensive, with pigmented patches in posteroventral part. Pronotum trapezoid, truncate at apex, in middle part with marked longitudinal, sclerotized suture, differing from pronotal surface by absence of reticulate structure. Similar structure in meso- and metathorax, indistinct in abdominal segments. Thoracic terga with considerably widened lateral plates and four tubercles at posterior margin. Prosternum prolonged, prothoracic precoxalia absent, episterna extensive, attached to prosternum. Meso- and metasternum with pair of tubercles (figure 22). Extensive spiracular plates with spiracles at margin and bottom of extensive cavity in both, meso- and metathorax (figures 22, 24). Legs slender, relatively long, long trochanters divided in anterior and posterior part. Abdomen with large lateral processes, spiracles on margin and bottom of caves in segments A1–A8. Sterna A1–A8 with slender posterolateral processes, upper pleurites extensive, with similar process in outer posterior angle. Lower pleurites very small, with short process only in segments A3–A8. Segment A9 widest at apex, with short, fixed urogomphi (figures 21, 23).

Young larva (spec. #2). Differs in shorter and partly missing processes from older larvae. No cavities at spiracles present, small spiracular scar in place where cavity located in older larvae.

Measurements. spec. #1: BL 39 mm, PL 7.2 mm, PW 11 mm, width of mesonotum 14 mm; spec #2: BL 11 mm.

Material examined. Philippines, Mindanao , Kitanglad, v.1999, two female larvae ( LMBC), here described. In addition we have examined various instars of eight morphologically different, unidentified species from the Philippines, Peninsular Malaysia, Sumatra and Java .

Remarks. About 15 species of trilobite larvae may be collected in Peninsular Malaysia, Borneo, Sumatra and Java, three of them are known as males. Other species were not yet described. A. Wong, Singapore is currently studying the group. Platerodrilus is closely related to Duliticola . It differs only in the structure of male genitalia (Wong, pers. comm.).

Besides the typical ‘trilobite larva’ described here, the first author has also collected a robust larva belonging to the Duliticola group but lacking the widened lateral plates and having a convex body. This larva, differs strongly in the general appearance, but has the same structure of spiracles, cranium, mouthparts and antennae and is doubtlessly related to Duliticola .