Micridium vittatum ( Motschulsky, 1845 )

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 : 251-252

Micridium vittatum ( Motschulsky, 1845) as Trichopteryx vittata

( Figs. 3 a/b, 31)

Habitus Fig. 3 a/b. Length 0.53 mm. Colour yellow, head darker. Finely pubescent. Antonnomeres 3–11 length 0.19 mm. Width across eyes 0.15mm. Pronotum length 0.16 mm, width 0.21 mm, widest in anterior half, more shining than elytra, with fine scattered punctures more obvious in anterior than posterior half, lateral margins slightly sinuate. Fig. 31 . Elytra length 0.35 mm, width 0.24 mm, more strongly punctured than pronotum, widest in front of middle and tapering posteriorly. Wings visible through elytra.

Remarks. The description, figure and measurements are based on two syntypes in the BMNH mounted on a single piece of mica(?) and bearing labels: ' Micridium vittatum' (on a card immediately under the specimens, possibly in Motschulsky's hand); ' Micridium vittatum ; Type from Motschulsky ; Russia [followed by a short, unreadable word] 1845' (in Matthews' hand on a pale green card, the posterior corners cut off); '2322. 2323' (Matthews/Mason collection numbers); ' Matthews coll 1904 - 120' ( BMNH accession number) and ' Syntype' (added by the BMNH). ( Figs. 3 a/b).

A slide preparation of two further specimens (one apparently previously unnoticed being very faint and to one side) bearing a label in Matthews' hand ' Micridium vittatum –maxilla Labium etc. 1865 44' also exist in the BMNH but it is not clear that these are the same species as those above. Further cards attached to these specimens, also apparently in Matthews' hand, are inscribed: 'Ex? 1892 All parts distinct, three joints of the tarsi very distinct' (two front corners of the card are cut off); 'In this preparation the Mentum etc are attached to one of the the[sic] maxilla 44' (green card, the two back corners cut off); '44' (green card); '2981' (Matthews/Mason collection number); and 'Matthews coll 1904 - 120' (BMNH accession number).

Some details of the ventral surfaces of the two syntypes are just visible through the mica and confirm that the insects show the mesoventral features confirming their determination as Micridium . For the reasons given above the insects have not been dissected so that their sex is not known.

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.