Pieza pi, 2002

Evenhuis, Neal L., 2002, Pieza, a new genus of microbombyliids from the New World (Diptera: Mythicomyiidae), Zootaxa 36, pp. 1-28 : 19-20

Pieza pi , sp. nov.

Male. Length: 0.90­0.98 mm. Head. Eyes dichoptic; ocelli forming a narrow triangle; lateral ocellus 1.5 its diameter from inner eye margin; frons slightly longer than wide, depressed medially, yellow from level of median ocellus to antennae, with medial black spot; antenna black, scape minute; pedicel slightly wider than long; first flagellomere short, ovoid, broadest at or slightly beyond middle, slightly longer than wide; length of second flagellomere equal to width of first flagellomere; face brownish, narrowly yellow beneath antennae; proboscis black, projecting beyond oral margin for distance shorter than head height; occiput black on upper half, yellow on lower half, with sparse black hairs.

Thorax. Mesonotum dull brownish black with incomplete yellow admedian vittae, each one not quite reaching interhumeral triangle caudally; humeral callus, broad interhumeral triangular mark, lateral margin, postalar callus, admedian vitta, and prescutellar area yellow; black color of mesonotum almost reaching base of scutellum laterally; dorsum of mesonotum with scattered black hairs; scutellum yellow with scattered dark hairs; pleura black and yellow, anepisternum with upper portion yellow; medial longitudinalyellow stripe present; legs yellow except for brown middle one­third of femora; halter with stem and knob yellow to whitish.

Wing. Hyaline; veins dark brown; costa ending at midpoint between end of veins R4+5 and M1; vein R2+3 arising at nearly 90°; celldm narrowed apically; vein at base of cell m1 shorter than r­m crossvein.

Abdomen. Dorsum brownish; tergite II with yellowish white anteriorly, laterally and posteriorly, tergites III­VI with narrow yellow to yellowish white fasciae on posterior margin of each segment; venter yellow.

Genitalia ( Fig. 21 ). In lateral view with gonocoxite subrhomboid, hemispherical in dorsal view; gonostyli not evident, gonocoxal apodemes narrow caudally, flaring to broad apex; aedeagus with broad, cone­shaped bulb basally, leading to long, thin bifid aedeagal tip; aedeagal apodeme large, axe­shaped, with small, thin lateral vanes; lateral rami slightly broadened distally in ventral view; epandrium elongate ovoid, pseudo­surstylus incurved, not evident in lateral view; cercus hook­shaped, not exserted.

Female as in male. Genitalia not dissected.

Types. Holotype female and allotype male from the BAHAMAS: Cat I: Bennetts Harbour, 24.iii.1953, E.B. Hayden, deposited in AMNH. Paratypes: BAHAMAS: Berry Is: Little Harbour Cay, 1 female, 1.v.1953, E.B. Hayden & L. Giovannoli. Turks and Caicos Is: West Caicos I: 1 female, 4.ii.1953, E.B. Hayden & L. Giovannoli (all in AMNH). MEXICO: [Morelos]: Guerrero: 1 female, Revolcadero, 2.xii.1966, N.L.H. Krauss ( USNM).

All specimens except the Mexican specimen were collected as part of the Van Voast­ AMNH Bahamas Islands Expedition, which collected insects throughout the Bahamas from Grand Bahama Island south to the Turks and Caicos from December 1952 to May 1953. Rabb and Hayden (1957) gave details of the expedition including data concerning vegetation and climate at each of the collecting localities.

Remarks. Little variation has been noted in these specimens due to the paucity of material at hand. Given the apparent long flight period for pi (February through May), it can be assumed that it is more widespread throughout the Bahamas and possibly can be found in adjacent West Indian islands.

This species represents one of the three species of Pieza known from the West Indies, and is the first record for the family in the Bahamas. Johnson (1908) recorded 8 species of bombyliids from the Bahamas, but no mythicomyiids. Vaurie (1952), in his report of the insects of Bimini, mentioned Bombyliidae as having been collected there, but did not name any. I have not seen any mythicomyiids from Bimini collections, but there is no reason to doubt that they occur there.

Etymology. The species epithet derives from the sixteenth letter of the Greek alphabet,. It is treated as a noun in apposition.

Distribution. Known from the Bahamas and Turks and Caicos islands in the Caribbean and the single specimen from southern Mexico.

Figures

FIGURES 20 ­ 21. 20, Pieza sinclairi, sp. nov., male genitalia; a. lateral view; b. epiphallic complex, dorsal view; c. gonocoxites, ventral view; d. epandrium, ventral view. 21, Male genitalia of Pieza pi, sp. nov.; a. lateral view; b. epiphallic complex, dorsal view; c. gonocoxites, ventral view.