Micridium foveatum, Darby, Michael, 2017

Darby, Michael, 2017, Taxonomic review of the genera Micridium Motschulsky, 1869 and Micridina Johnson, 1969 (Coleoptera: Ptiliidae) with eleven new species including the first records from South America and Madagascar, Zootaxa 4242 (2), pp. 233-254 : 242

Micridium foveatum sp.n.

( Figs. 13 , 21 , 40 , 46 , 59 , 64 , 75 , 85, 91, 102)

Habitus Fig. 13 . Length 0.64 mm. Colour dark brown, pubescence, antennae and legs dusky yellow. Length of antennomeres 3–11 0.24 mm, antennomere 11 with branched sensillae, Fig. 46 . Width across eyes 0.18 mm. Mentum: sides almost parallel expanded laterally at anterior corners, submentum with 3 setae, Fig. 40 . Pronotum without linear depressions but with two groups of large setal depressions (numbers and positions slightly variable between specimens and some with a few scattered centrally) length 0.16 mm, width 0.22 mm, Fig. 21 . Elytra length 0.42 mm, width 0.28 mm. Mesoventrum: keel narrow between mesocoxae, splitting anteriorly into two short projections which reach half way to the collar; collar with a small semicircular cap medially placed on the anterior margin and a medially placed bifid posterior projection, Fig. 59 . Mesepiventra without reticulation, sinuate in posterior half with rounded hind angles. Metaventrum: metepiventral sutures short reaching +/– 1/4 length of the sclerite, Fig. 64 . Pygidium with a sharp apical point Fig. 102. Wings of usual ptiliid type.

Male: posterior intercoxal process of metaventrum with a fringe of 8 flattened setae extending posteriorly beyond the metacoxal plates. Aedeagus: shape difficult to interpret, Fig. 85.

Female: spermatheca Fig. 75 .

Etymology. Named after the pronotal depressions.

Diagnosis. The form of the mesoventrum quickly distinguishes this species from all others.

Type data: Holotype: ♀, Chile, Llanquihue Pr., Lago Chapo , 13.5 km E Correntoso, site 656, Valdivian rainfor., window trap, 310m, 16–27.xii.1982, A. Newton & M. Thayer ( FMNH) . Paratypes: 16 examples, same data as holotype ( FMNH, BMNH) ; 3 examples, Chile, Valdivia Pr., 4.1km W Anticura, trap site 663, Valdivian rainfor., window trap, 270m, 19–25.xii.1982, A. Newton & M. Thayer ( FMNH) ; 2 examples, Chile, Valdivia Pr., 4.1km W Anticura, trap site 663, Valdivian rain for., leaf litter on forest floor, 270m, 19–25.xii.1982, A. Newton & M. Thayer ( FMNH) ; 1 example, Chile, Osorno Pr., Parque Nac. Puyehue, Antillanca road, trap site 661, Valdivian rainfor., 690m, 18–24.xii.1982, A. Newton & M. Thayer ( FMNH) ; 11 examples, Chile, Osorno Pr., Parque Nac. Puyehue, 4.1 km E Anticura, trap site 662, Valdivian rainfor., forest leaf and log litter, 430m, 19–26.xii.1982, A. Newton & M. Thayer ( FMNH, BMNH) .

Figures

FIGURES 1 – 14. Micridium habitus. 1. M. angulicolle (Fairmaire) 2. M. halidaii (Matthews) 3. M. vittatum Motschulsky 4. M. lineatum Le Conte 5. M. rhodeanum (Casey) 6. M. hilli (Johnson) 7. M. johnsoni sp. n. 8. M. elegans sp. n. 9. M. oweni sp. n. 10. M. attenboroughi sp. n. 11. M. boliviense sp. n. 12. M. newtoni sp. n. 13. M. foveatum sp. n. 14. M. thayerae sp. n. 15. M. proprium sp. n. 16. M. quadridens sp. n.

FIGURES 17 – 32. Micridium pronotums. 17. M. quadridens sp. n. x 605. 18. M. inornatum sp. n. x 590. 19. M. boliviense sp. n. x 625. 20. M. newtoni sp. n. x 695. 21. M. foveatum sp. n. x 830. 22. M. johnsoni sp. n. x 790. 23. M. elegans sp. n. x 810. 24. M. thayerae sp. n. x 650. 25. M. halidaii (Matthews) x 770. 26. M. hilli (Johnson) x 740. 27. M. oweni sp. n. x 575. 28. M. attenboroughi sp. n. x 675. 29. M. angulicolle (Fairmaire). 30. M. rhodeanum (Casey) 31. M. vittatum Motschulsky 32. M. lineatum Le Conte.

FIGURES 33 – 41. Micridium mentums. 33. M. oweni sp. n. x 1420. 34. M. attenboroughi sp. n. x 1840. 35. M. boliviense sp. n. x 1280. 36. M. elegans sp. n. x 1320. 37. M. proprium sp. n. x 2360. 38. M. quadridens sp. n. x 1900. 39. M. johnsoni sp. n. x 1600. 40. M. foveatum sp. n. x 1220. 41. M. thayerae sp. n. x 1160.

FIGURES 42 – 46. Micridium antennae. 42. M. quadridens sp. n. showing more rounded antennomeres on shorter antennae. 43. M. thayerae sp. n. 44. M. elegans sp. n. showing more elongate antennomeres. 45. M. johnsoni sp. n. x 2000 antennomeres 9 – 11 showing single sensillae on 10 & 11. 46. M. foveatum sp. n. x 1800 antennomeres 10 & 11 showing branched sensillae.

FIGURES 47 – 60. Micridium mesoventra. 47. M. inornatum sp. n. x 540. 48. M. quadridens sp. n. x 710. 49. M. boliviense sp. n. x 695. 50. M. attenboroughi sp. n. x 870. 51. M. proprium sp. n. x 920. 52. M. newtoni sp. n. 53. M. johnsoni sp. n. x 655. 54. M. thayerae sp. n. x 860. 55. M. halidaii (Matthews) x 615. 56. M. oweni sp. n. x 585. 57. M. elegans sp. n. x 705. 58. M. hilli (Johnson) x 760. 59. M. foveatum sp. n. x 1300. 60. M. rhodeanum (Casey) x 545.

FIGURES 61 – 71. Micridium metepiventral sutures. 61. M. johnsoni sp. n. x 530. 62. M. thayerae sp. n. x 505. 63. M. attenboroughi sp. n. x 670. 64. M. foveatum sp. n. x 735. 65. M. quadridens sp. n. x 710. 66. M. elegans sp. n. x 730. 67. M. oweni sp. n. x 585. 68. M. hilli (Johnson) x 760. 69. M. halidaii (Matthews) x 615. 70. M. newtoni sp. n. x 710. 71. M. rhodeanum (Casey) x 545.

FIGURES 72 – 81. Micridium spermathecae. 72 a / b. M. attenboroughi sp. n. 73. M. boliviense sp. n. 74. M. elegans sp. n. 75. M. foveatum sp. n. 76. M. halidaii (Matthews) (may have been broken or distorted in preparation). 77 a / b. M. johnsoni sp. n. 78. M. hilli (Johnson) 79. M. thayerae sp. n. 80. M. inornatum sp. n. 81. M. newtoni sp. n.