A new tribe is established in the Limnichidae, Limnichinae, for a new genus and species, Wooldridge us perforatus, from Sabah, Malaysia. Two autapomorphic characters distinguish Wooldridgeini from the two other tribes ofthe subfamily Limnichinae; 1) the mesotarsus and metatarsus join their respective tibia ventrally (medially) and preapically instead of the usual apical only connection and 2) a large pore, presumed to be an opening of a prothoracic gland, is present on each hypomeron. Distinguishing characters are illustrated by scanning electron micrographs and line drawings. A key to the three tribes included in the Limnichinae is provided

Spangler, Paul J.

English

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INSECTA MUNDI, Vol. 12, No. 3-4, September-December, 1998  181 A new tribe, genus, and species oflimnichid beetle, Wooldridge us perforatus, from Malaysia (Coleoptera: Limnichidae: W  ooldridgeini) Paul J. Spangler Department of Entomology, MRC-169 National Museum of Natural History, Smithsonian Institution Washington, D.C. 20560 Abstract.-A new  tribe is  established in the Limnichidae,  Limnichinae, for  a new  genus  and species, Wooldridge us perforatus, from Sabah, Malaysia. Two  autapomorphic characters distinguish Wooldridgeini from the two other tribes ofthe subfamily Limnichinae; 1) the mesotarsus and metatarsus join their respective tibia ventrally (medially) and preapically instead of the usual apical only connection and 2) a large pore, presumed to be an opening of a prothoracic gland, is present on each hypomeron. Distinguishing characters are illustrated by scanning electron micrographs and line drawings. A key to the three tribes included in the Limnichinae is provided. Specimens of the new tribe, genus, and species described  below  were  found  among a  variety of aquatic  and terrestrial  beetles  collected  for  the National Museum of Natural History, Smithsonian Institution,  by  Gary  F.  Hevel  and  Warren  E. Steiner in Sabah, northern Borneo in 1983. Wooldridgeini Spangler, new tribe Diagnosis.-Small,  length  less  than  2  mm. Broadly ovate and convex dorsally (Figures 1,  2). This new taxon may be readily distinguished from all other described limnichid taxa by the ventral (medial)  and  preapical  connection  of  the mesotarsus  and  metatarsus  to  their  respective tibia  (Figures  17,  18)  instead  of only  an  apical connection  as  found  in  other limnichid  taxa.  A large  pore,  not  known  in  other  taxa  of  the Limnichidae, is present on each hypomeron of this new taxon. Wooldridgeus Spangler, new genus Diagnosis.-Characters  of the  tribe  and  the following.  Length,  1.90-2.00  mm.  Venter  with concavity  for  reception  of  legs  (Figures 2, 16). Tarsal  formula  5-5-5.  Antenna,  11 segmented; with 3-segmented club.  Hypomeron with pore of prothoracic  gland  opening  near  each  lateral margin  (Figures  14,  15);  with  an  obliquely transverse  ridge  extending  mediad  from posterolateral  concavity  to  lateral  margins  of prosternum.  Epipleuron  very  broad  opposite mesocoxae, wider than width of mesofemur; with oblique, deep, apicomedial concavity for reception of distal part of mesotibia in repose (Figures  16 18). Description. Adult.-With characters of tribe and  those  given  in  diagnosis  of genus  and  the following.  Body  broadly  ovate;  almost  flat ventrally; moderately convex dorsally. Integument clothed  with  dense  pubescence;  pubescence comprised of setae of two types; one type slender, smooth,  and  aciculate;  second  type  broad  and longitudinally grooved (Figure 24). Head  hypognathous,  usually  retracted  into pronotum. Mouthparts often retracted. Maxillary palpus, 4 segmented. Labial palpus, 3 segmented. Clypeus  transversely  rectangular  with  short oblique grooves laterally which extend onto head; labroclypeal suture deep,  distinct (Figures  4,  6). Labrum subquadrate, apicolateral angles broadly rounded (Figures 5,  6). Pronotum convex; widest across base (Figure 1);  deeply  emarginate  for  reception  of  head; margins  narrowly  rimmed;  posterior  margin sinuate. Elytron punctate and densely pubescent. Hind  wing  (Figure  10)  with  reduced  venation; without a  radial cross  vein,  cubito-anal vein,  or anal  cell;  radial-medius  indistinct;  medius shortened,  joined  with  cubitus  distally;  of anal veins, only anal vein 2 present. Prosternum long anterior to procoxae; rimmed anteriorly. Prosternal process convex,  about as wide as profemur at its midlength; apex moderately  rounded. Mesosternum short  but  widely  transverse  and  bandlike, 182  Volume 12, No. 3-4, September-December, 1998, INSECTA MUNDI moderately flat; anterior margin sinuate; posterior margin truncate. Metasternum moderately convex, wide, deeply grooved  apicolaterally for  reception of mesotibia. Antecoxal sclerite distinct. Metacoxa transversely  elongate,  grooved  posteriorly  for reception of metafemur. All tarsal claws  simple, not toothed (Figure 22). Abdomen with 5 visible segments. Segment 1 pubescent  with  exception  of  oblique  glabrous concavity  for  reception  of  metafemur  and metatibia.  Segments  2-5  pubescent  except subtriangular glabrous area on segments 2 and 3; glabrous  area  may  be  result  of  abrasion  from lateral movements of metatarsi, which do  not fit into  concavities.  Last  segment  emarginate apicomedially (Figure 25). I  consider  the  two  unique  and  distinctive characters  1)  the  unique  insertion  of  the mesotarsus and metatarsus to the tibia and 2) the large hypomeral pore to be autapomorphic Type Species of the Genus.  Wooldridge us perforatus Spangler, by monotypy. Etymology.-Wooldridgeus,  a  patronym dedicated  to  my  colleague  Dr.  David  P. Wooldridge,  who  has  contributed  extensively to the knowledge of the world's taxa included in the Limnichidae. The generic name is masculine. Wooldridgeus perforatus Spangler, new species Figures 1-32 Diagnosis.-The single  species  known in this genus  may  be  recognized  by  the  characters included in the diagnoses of the tribe and genus plus the following. Holotype  (Male}.-Body  Form  and  Size: Broadly  ovate,  moderately  convex  dorsally. Length, 1.90 mm; greatest width across basal fifth of elytra, 1.43 mm. Color: Cuticle black; pubescence golden yellow. Head: Pubescent. Sub  quadrangular, with eyes not  visible  from  above  (Figure  3).  Sides  flat, obliquely rimmed dorsally (Figures 4,  8).  Apical margin on each side of clypeus with short, narrow groove  (Figure  4).  Clypeus  sparsely  pubescent; labrum  densely  pubescent  (Figures  4,  5,  6). Antennae with segments 1,2, and 9-11 longest and broadest;  segments  3-8  cylindrical  and  narrow; segments  2-11  moderately  densely  pubescent; segments 9-11  become progressively broader and more densely pubescent (Figure 8).  Maxilla with palpus  pubescent;  apical segment long,  swollen, with  sensilla  on  small  apical  protuberance (Figures 5, 12,  13).  Galea  and lacinia each with apical tuft of dense setae (Figure 9). Labial palpus with  apical  segment  longest;  apical  segment cylindrical and sparsely pubescent (Figure 9), with sensilla on apex (Figure 11). Thorax:  Pronotum  broadest  and  trisinuate across  base.  Hypomeron  flat;  microreticulate; without pubescence except sparsely along margins and  in  each  prothoracic  pore.  Scutellum subtriangular (Figure 23). Elytron microreticulate; cuticle  with  2  types  of setae  (Figures  23,  24). Epipleuron  pubescent  and  very  broad  opposite metasternum and then widely rimmed along inner margin (Figures 16-18).  Pro  sternum with cuticle microreticulate and moderately pubescent. Protarsi (male) with long spatulate setae on ventral surface (Figures 5, 16, 20, 21). Mesotibial apex with 5 stout spurs on truncate apex (Figures 18, 19). Mesotarsi and  metatarsi  arising  subapically  on  ventral (medial)  surface  of  mesotibial  and  metatibial apices respectively (Figures 17-19). Abdomen: As described for  genus. Genitalia: As illustrated (Figures 26-29). Female.-Externally similar to male. Genitalia as illustrated (Figures 30-32). Variations.-The  only variation  noted  among the 42 specimens is in size; lengths ranged from 1.86 to 2.08 mm; width ranged from  1.38 to 1.57 mm. Type  data.-Holotype,  _:  Malaysia:  Sabah, Telupid (25 km E), 17 Aug 1983, at blacklight, G.F. Hevel &  W.E. Steiner; deposited in the National Museum  of  Natural  History,  Smithsonian Institution.  Allotype:  Same  data  as  holotype. Paratypes: Same data as holotype, 40 specimens. Etymology.-Named perforatus because of the unusual subapical attachment of the mesotarsus and metatarsus, which perforates the side of the tibia (Figures 18, 19). Habitat.-The specimens described above were collected along with other small aquatic beetles at blacklight  at  a  logging  area  on  a  semi-forested hilltop, 25 kilometers east of Telupid. The site was not clear cut and some tall trees and old cut logs were present in the area. Discussion.-In  reviewing  the  literature  in order to identify this new taxon, I  consulted the most  recent  key  by  Wooldridge  (1975);  this included 3  subfamilies  and 15  genera known to occur in the Western Hemisphere. In that key, the new genus traced to  the subfamily Limnichinae and  the  genus  Limnichus  Latreille  (1829). INSECTA MUNDI, Vol. 12, No. 3-4, September-December, 1998  183 Figures 1-9. Wooldridgeus perforatus, new genus, new species: 1, habitus, dorsal view, X40; 2, habitus, ventral  view, X40; 3, head, dorsal  view,X145; 4, head, aboral  view,X150; 5, head, adoralview,X170; 6, mouthparts, X400; 7, antennal  base,X500; 8, antenna and eye, X170; 9, lacinia and galea apices, last segment oflabial pal  pus, X800. 184  Volume 12, No. 3-4, September-December, 1998, INSECTA MUNDI However, the presence of the unique autapomorhic characters  given  in  the  tribal  and  generic diagnoses of the new genus readily distinguishes Wooldridge us  from  Lim-nichus  and  all  of  the genera presently included in the Limnichinae of the New World. In  addition,  although  I  checked  SaW's  key (1966) to the subfamilies and genera of Japanese Limnichidae,  reviewed  descriptions  of  other genera ofthe Old World, and examined taxa of Old World  genera  in  the  collections  of  National Museum of Natural History, I was unable to find any limnichid genus other than Wooldridge us with the  unique  attachment  of the  mesotarsus  and metatarsus  to  their  respective  tibia  and  the hypomeral  pores. Because Wooldridgeus is the only genus known in  the  Limnichidae  with  the  two  distinctive autapomorphic characters, I place the genus in a new tribe in the Limnichinae. A key to the three tribes recognized in the Limnichinae follows. Key to tribes of the subfamily Limnichinae 1.  Hypomeron each with a  large pore (Figures 14, 15); mesotarsus and metatarsus connected ven-trally (medially) and pre  apically to respective tibia (Figures 18, 19) ......................................... . .................. Wooldridgeini Spangler, new tribe Hypomeron without a pore. Mesotarsus and meta-tarsus connected only to apex of  respective tibia ............................................................................ 2 2.  Pronotum with deep concavity on each side for reception of antenna in repose; total length 0.8 1.2mm ................................................................ . ................ Bothriophorini Mulsant &  Rey, 1868 Pronotum without concavity on each side; total length, variable, 1.24.5 mm .............................. . .......................... ....... Limnichini Erichson, 1877 Acknowledgments For their assistance with this study, I thank the following  individuals  from  the  Smithsonian Institution:  Gary  F.  Hevel,  Museum  Specialist, and Warren E.  Steiner, Museum Specialist, who collected  the  specimens  of  this  new  limnichid genus  along  with  many  other  aquatic  and semiaquatic  beetles  for  my  research  interests during their fieldwork in Sabah, Malaysia; Walter Brown,  Manager,  Scanning Electron  Microscope Laboratory,  for  assistance  in  obtaining  the micrographs; Young T. Sohn, Scientific Illustrator, for  the  line  drawings  and  assistance  with preparation of the plates;  and G.F.  Hevel,  W.E. Steiner for reviewing the manuscript. References Erichson, W.  F.  1847.  Naturgeschichte der Insecten Deutschlands. Abt. 1, Coleoptera, 3(Lief  4):481640. Hinton, H. E. 1939. An Inquiry into the Natural Classi-ficationof the Dryopoidea, Based Partly on a Study of Their Internal Anatomy (Col.).  Transactions of the Entomological Society of London 89:133-184. Latreille, P. A. 1829. Les Crustaces, les Arachnides et les  Insectes,  distribues  en  "Familles  Naturelles, ouvrage Format les Tomes 4 et 5 de Celui de M.  Ie Baron Cuvier sur Ie Regne Animal. (Deuxieme Edi-tion), Volume 1, 584 pages. Paris. Mulsant, E., &  C.  Rey, 1868. Historie Naturelle des Coleopteres de France. Gibbicolles.  226 pages, 14 plates. Deyrolle, Paris Sata, M. 1966. The Limnichid-Beetles of Japan. Trans-actions ofthe Shikoku Entomological Society 9(2):55 62 Wooldridge, D. P. 1975. A key to the N ew World Genera of the Beetle Family Limnichidae.  Entomological News 86(1 & 2):14. i-----1.0mm ----I Figure 10. Wooldridgeus perforatus, new genus, new species; hind wing. INSECTA MUNDI, Vol. 12, No. 3-4, September-December, 1998  185 Figures 11-19. Wooldridge  us perforatus, new genus, new species: 11, sensilla, labial palpus, last segment, X4,OOO; 12, maxillary pal  pus, last segment, X1,300; 13, sensilla, maxillary palpus, last segment, X8,OOO; 14, Hypomeron and prothoracic gland pore, X200; 15, prothoracic gland pore,X800; 16, prosternum, mesosternum, and metasternum, X60; 17, middle and hind legs and abdomen,X60; 18, middle leg and metasternum, X170; 19, meso  tibial and mesotarsaljunction, X1,300. 186  Volume 12, No. 3-4, September-December, 1998, INSECTA MUNDI Figures  20·25. Wooldridge us  perforatus, new genus, new species: 20, protarsus, X450; 21, protarsus, ventral  setae, male, XI,200; 22, protarsal claws, Xl,  700; 23, scutellum, X400; 24, cuticular setal types, XI,500; 25, last abdominal segment emargination, X700. INSECTA MUNDI, Vol. 12, No. 3-4, September-December, 1998  187 I O.2mm 1 ®  ® Figures 26-32. Wooldridgeus perforatus, new genus, new species: Figures 26-29, male genitalia: 26, aedeagus, ventral view; 27, sternum 9, ventral  view; 28, sternum 9, lateral view; 29, sternum 10, ventral  view. Figures 30-32, female genitalia: 30, ovipositor, dorsal view; 31, ovipositor, lateral view; 32, sternum 9, ventral view. 

A new tribe, genus, and species of limnichid beetle, Wooldridge us perforatus, from Malaysia (Coleoptera: Limnichidae: W ooldridgeini)

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