ANNALES ZOOLOGIO (W arszaw a), 2000, 50(4): 559-573 THE LARVAE OF LEIESTINAE WITH NOTES ON THE PHYLOGENY OF ENDOMYCHIDAE (COLEOPTERA: CUCUJOIDEA) B olesław B urakowski an d S tanisław A dam Ś lipiński Muzeum i Instytut Zoologii PAN, Wilcza 64, 00-679 Warszawa, Poland, e-rna i l: a da msli @robal. rn iiz. waw.pl Abstract.— Larvae representing three genera of Leiestinae (Coleoptera, Endomychidae) are described and illustrated: Leiestes seminiger (Gyllenhal) (Poland, Białowieża National Park), Phymaphora pulchella Newman (USA, Virginia), and Rhanidea unicolor (Ziegler) (USA, New Jersey). The larval characters of Endomychidae and its subfamilies are dis­ cussed, and the key to the known genera is provided. The larval characters show only partial congruence with the recent family classification based on the adult data. Key words. — Coleoptera, Endomychidae, Leiestinae, Leiestes, Rhanidea, Phymaphora, larvae, biology, mycophagy. I ntroduction the procoxal cavity with narrow slit (Tomaszewska 2000a). Their larvae have not been described in detail. Because of the peculiar pseudotrimerous tarsi of The larva of Rhanidea unicolot' is illustrated in most large and aposematic species of Endomychidae, Lawrence (1991), while both Phymaphora and the group has always been closely associated with Rhanidea are jointly characterized in Lawrence (1999). Coccinellidae, and indeed some coccinellid genera were Below we present descriptions and illustrations of the described as endomychids (e.g., Mimolitophilus or immature stages of Leiestes seminiger based on the lar­ Monocoryna) and vice versa (e. g., Cyclotoma). While vae collected by the senior author in the Białowieża most of the coccinellids are either predaceous or herbiv­ National Park, north eastern Poland, and supplementary orous, Endomychidae are primarily fungivorous descriptions of Phymaphora and Rhanidea. (Lawrence 1991) with the notable exception of the preda­ Since the data of Tomaszewska (2000b) includes only ceous larva of Saula described by Sasaji (1978a). Both adult characters, we also tried to summarize the avail­ families are currently classified within the superfamily able larval characters to investigate distribution of larval Cucujoidea, and are recognized as members of the cery- character states among the recognized subfamilies. To lonid series by Crowson (1960) and Ślipiński and stimulate further interests in the endomychid natural his­ Pakaluk (1991). Very little information is published on tory we consulted all papers containing larval descrip­ biology and immature stages of Endomychidae tions of Endomychidae, and constructed a key to the gen­ (Lawrence 1991). Of more than 120 currently recognized era based on these descriptions and our larval collection. genera, larvae of 25 genera have been described so far, mostly from the northern hemisphere. In the recent clas­ L arvae o f L e ie s t in a e sification of Endomychidae (Tomaszewska 2000b) twelve subfamilies have been recognized, of which larvae Leiestes seminiger ('Gyllenhal) remain unknown for Eupsilobiinae (Pakaluk and (Figs 1-19) Ślipiński 1990) and Danascelinae (Tomaszewska 2000b). The Australian genus Periptyctus Blackburn included Diagnosis. The larva of Leiestes seminiger is easily in the subfamily Epipocinae (McHugh and Pakaluk 1977) distinguished from all known endomychid larvae by the belongs in the Corylophidae (Ślipiński and Tomaszew­ biforous spiracles and the peculiar tubercles on the ska, in prep.), and is not discussed further in this paper. eighth abdominal tergite. Leiestinae include 6 genera distributed in Europe, Measurements, length 4.6 mm; head width 0.64 mm; Japan and North America. Leiestinae adults are rather pronotum width 0.9 mm; width of 9th abdominal segment small beetles with distinctly clubbed antennae, simple 0.56 mm. tarsomeres, very narrow, bicarinate mesosternum, hid­ Mature larva. Body elongate, approaching fusiform den antennal insertions, concealed mesotrochantin and (Fig. 1), widest at middle, subcylindrical, slightly flat­ http://rcin.org.pl 5 6 0 B . B u r a k o w s k i and S. A. Ś l ip iń sk i Figures 1-3. Leiestes seminiger , larva. 1, 2. Mature larva: (1) dorsal; (2) lateral. 3. First-instar larva, dorsal. tened dorsally, weakly constricted between segments, thorax; rim of occipital foramen distinctly thickened. without urogomphi. Color ochreous, each tergite of tho­ Stemmata 3 on lateral side (Fig. 2) forming a triangle. rax with two brownish patches; first eight abdominal ter- Frontal sutures lyriform, almost complete anteriorly, gites brownish posteriorly. Body feebly sclerotized meeting posteriorly; coronal suture absent. Frons broad, except for head, mandibles, and tergites which are mod­ with 2 setae and 2 pores in front of middle; epistomal erately strongly sclerotized. Cuticle of dorsal surfaces margin with 2 long setae near talus. Epicranium with one finely and rather densely microtuberculate, with trans­ pair of long setae and two pairs of short setae near verse or oblique rows of asperities visible under 100 x frontal suture, and seven pairs of setae on lateral sides. magnification (Fig. 18). Vestiture consists of scattered Frontoclypeal suture weak, indistinct. Clypeus trape­ simple apically acute setae, and long, sparse stick-like zoidal, about 0.3 x as wide as head capsule, with 2 pairs setae on thoracic and abdominal tergites. of setae. Labrum (Figs 6, 7) free, 0.3 x as long as wide, Head (Figs 4, 5) prognathous and protracted, with 4 pairs of setae near anterior margin and 2 setae on depressed, 0.6 x as long as wide, and 0.7 x as wide as pro­ median area. Epipharynx (Fig. 7) membranous; anterior­ http://rcin.org.pl THE LARVAE OF LEIESTINAE 561 ypfc-w&i??:. ?■••••• Figures 4-11. Leiestes seminiger, mature larva. (4) Head, dorsal; (5) head, ventral; (6) labrum, dorsal; (7) labrum-epipharynx, ventral; (8) maxilla; (9) right mandible, ventral; (10) same, mesal; (11) same, dorsal. ly furnished with 8 placoid sensilla, posteromedian part Mandible (Figs 9-11) subtriangular, bidentate apically; with 2 clusters of numerous microtrichia obliquely direct­ incisor edge serrate apically; external margin with 2 long ed to midline; 4 placoid sensilla at middle. Antenna (Figs setae; dorsal surface with 2 campaniform sensilla; mola 12, 13) short, 3-segmented, situated on circular mem­ narrow but well developed bearing transverse rows of brane; insertion fairly close to mandibular articulations. blunt tubercles or ridges. Ventral mouthparts (Fig. 5) Relative length of antennomeres as 1.0:2.5:3.0; sensory retracted, jointly about as long as wide. Maxilla (Fig. 8) appendage about 0.7 x as long as antennomere 3. slender, movable; cardo subtriangular bearing single Antennomere 1 lacks setae but with 2 campaniform sen­ seta, juxtacardo oblique; stipes with 2 setae at outer mar­ silla; 2nd with 3 long setae near apex, and conical senso­ gin; mala 2 x as long as wide, rounded at apex, with ry appendage situated ventro-laterally; antennomere 3 numerous setae close to apical margin (2 of them blunt dome-shaped, with 3 long setae, 3 solenidia (1 styliform, apically), and 2 setae along inner margin. Maxillary palp 2 setiform), the longest solenidium thickened at base. 3-segmented based on membranous palpifer bearing 2 http://rcin.org.pl 5 6 2 B. Burakowski and S. A. Ślipiński setae; palpomere 1 with 2 pores, 2nd with single seta and ryngeal sclerome bearing anterior membranous rods and 2 pores, the terminal segment bearing 2 short setae, sin­ posterior sclerotized processes; hypopharyngeal bracon gle pore and a group of minute papillae at apex. Labium aligamentous. Hypostomal rods long, slightly diverging (Figs 5, 14) with mentum fused to submentum, with four posteriorly (Fig. 5). setae; prementum well separated from mentum with 2 Thorax (Figs 1, 2) about 0.3 x as long as body length, setae; labial palps 2-segmented, first palpomere short, each tergum transverse, sclerotized and divided by a the terminal one much longer, cone-shaped, bearing pale longitudinal line. Protontum about 0.5 x as long as minute papillae at apex; ligula reduced to a small mem­ wide, widest at middle; anterior angles broadly rounded; branous protuberance bearing two rigid setae and each half of tergite bears 4 long and 2 short pointed numerous sensilla dorsally. Hypopharynx (Fig. 15) mem­ setae, and 2 stick-like setae posteriorly arranged as in branous anteriorly, limited posteriorly by dark hypopha- Fig. 1; surfaces granulose, especially near hind margin. Figures 12-19. Lelestes seminiger, larva. (12) Antenna, dorsal; (13) antenna, apical view; (14) prementum, dorsal; (15) hypopharynx; (16) abdominal spiracle; (17) leg; (18) tergites 7-9, lateral part; (19) right mandible, first-instar, ventral. http://rcin.org.pl THE LARVAE OF LEIESTINAE 5 6 3 Meso- and metathorax similar in size, each about 0.4 x of mesothorax. The number of teeth or corrugations on as long as wide; half of each tergal plate bears 2 stick- either side of the orifce is about 24 in the thoracic spira- like, 4B5 minute, and one long seta laterally; surfaces of cle, and 20 in the abdominal one. terga granulose. Abdomen. Segments 1-7 subequal in length, each ter- Legs (Fig. 17) slender, relatively short, not visible gite with 4 stick-like setae, numerous minute setae and from above in normal position; all pairs subequal; coxae patches of granules and asperities (Fig. 18). Ventral sur- widely separated with short setae. Trochanter triangu- faces weakly sclerotized, whitish; lateral side of each of lar with 1 long and 3 short setae and four setae; femur segments 1-8 with protuberant epipleuron bearing 1 about 2 x as long as wide, dorsally with 1 seta and 2 long and 1 short seta; hypopleuron with 1 long seta; lat- pores, 4 setae ventrally and 2 short setae apically; tibio- erosternum with 1 long and 1 minute seta and medioster- tarsus 0.7 x as long as femur with 5 setae medially and 2 num with pair of long, and 3-4 pairs of short setae, short setae on antero-dorsal surface; claw broadened at Tergite VIII similar to the preceding one but bearing a base, bearing single seta.