Allograpta (Costarica) nishida Mengual & Thompson, 2009.
Mengual, X. Ruiz, C., Rojo S., Ståhls, G. & Thompson, F.C. (2009) A conspectus of the flower fly genus Allograpta (Diptera: Syrphidae) with description of a new subgenus and species. Zootaxa 2214, 1–28.
The subgenus Costarica has the face greatly produced anteriorly, with no tubercle but distinctly concave beneath antenna creating an appearance of a tubercle; oral opening about 5 times as long as wide, with oral apex greatly extended beyond level of antennal base; antennal pits distinctly separated; plumula absent; subscutellar fringe absent; wing microtrichose, without apical dark macula; metasternum bare; abdomen narrowly petiolate or elongate (Mengual et al. 2009).
Costarica is readily distinguished from all other Allograpta groups by the distinctive facial shape and by the dense thick appressed pile on 1st and 2nd terga in the males.
Allograpta nishida has 3rd & 4th terga with basal arcuate yellow fasciae; female 2nd tergum black with submedial fasciate yellow macula; pro- and mesofemora extensively black; and katepisternum and postalar callus brownish-black.
From original description (Mengual et al. 2009).
MALE.
Head: Face black medially, narrowly yellow laterally, short yellow pilose laterally; gena yellow, yellow pilose; lunule black; frontal triangle black except very narrowly yellow laterally, black pollinose and pilose; eye contiguity long, as long as vertical triangle; vertical triangle black, black pollinose and pilose; occiput yellow on ventral 1/3 and black on dorsal 2/3, white pollinose and yellow pilose on ventral 2/3, black pollinose and pilose on dorsal 1/3. Antenna brownish black except pale yellowish orange basoventral 1/3 of basoflagellomere, black pilose; arista black.
Thorax: Black except yellow posterior notopleuron, narrowly along base of scutellum, posterior 1/3 of anepisternum; yellow pilose except black pilose on dorsolaterally to wing base; calypter black; halter black except yellow capitulum. Legs: brownish black except yellow femoral apices and basal 1/3 of tibiae, black pilose except a few yellow pili on bases of femora. Wing: hyaline except costal and subcostal darker brownish, microtrichose.
Abdomen: Elongate, slightly narrower than thorax, shiny brownish black except for basal arcuate yellow fasciae on 3rd–4th terga and yellow lateral 1/3 of 1st tergum, black pilose except long lateral white pile and with dense thick brownish-black pile at dorsomedial part on 1st and 2nd terga; sterna dark; 1st sternum long white pilose; 2nd sternum short white pilose; 3rd–5th sterna appressed black pilose.
FEMALE.
Similar to male except for normal sexual dimorphism and: frons black except yellow laterally on ventral 2/3, dull, yellow pilose; 2nd tergum with arcuate yellow fascia narrowly divided medially. Abdomen mainly shiny, dull black pollinose on most of 2nd terga except apical margin and yellow fasciae, black pollinose areas on 3rd thru 5th terga restricted to medial area posterior to yellow fasciae.
Similar to Allograpta zumbadoi, the other species of the subgenus Costarica, but it has medial yellow macula on 3rd and 4th terga; female 2nd tergum entirely yellow; pro- and mesofemora extensively yellow; and katepisternum and postalar callus yellow.
Length: Male (1): body, 11.3 mm; wing, 10.0 mm. Female (2): body, 11.5–13.0 (12.3) mm; wing, 10.1– 11.8 (10.9) mm.
In the phylogenetic analysis by Mengual et al. (2009) based on morphological characters, the two species of Costarica (nishida and zumbadoi) were resolved together as sister group of the subgenus Rhinoprosopa.
Species only known from Costa Rica.
