Asyndetus interruptus (Loew)

Runyon, Justin B., 2020, The Dolichopodidae (Diptera) of Montserrat, West Indies, ZooKeys 966, pp. 57-151 : 57

Asyndetus interruptus (Loew)

Diaphorus interruptus Loew, 1861: 37.

Asyndetus interruptus Loew, 1869: 37.

Asyndetus bredini Robinson, 1975: 68.

Asyndetus wirthi Robinson, 1997: 479, syn. nov.

Material examined.

Belize: 2 ♂, 5 ♀, Stann Creek District, beach at Hopkins, 0-2 m, 16°51.16'N, 88°16.73'W, 23 April 2015, JB Runyon; 10 ♂, 3 ♀, same as previous, 18 March 2019. British Virgin Islands: 1 ♂, Prickly Pear Island, 18°30.18'N, 64°22.00'W, 3 November 2016, JB Runyon. Montserrat: 20 ♂, 8 ♀, Woodlands Beach, 16°45.75'N, 62°13.42'W, 20 June 2017, J.B. Runyon; 1 ♂, 2 ♀, Old Road Bay (beach), 16°44.623'N, 62°14.035'W, 22 June 2017, J.B. Runyon; 2 ♂, Fox’s Bay Beach, 16°43.59'N, 62°14.17'W, 24 June 2017, J.B. Runyon; 1 ♀, Rendezvous Bay Beach, 16°48.489'N, 62°12.296'W, 23 June 2017, J.B. Runyon; 2 ♀, Rendezvous Bay, 26 July 2005, yellow pan trap, V.G. Martinson. Nevis: 7 ♂, Winward Beach, 17°06.96'N, 62°32.91'W, 28 May 2017, J.B. Runyon. St. Kitts: 3 ♂, Majors Bay, 17°13.62'N, 62°38.91'W, 2 June 2017, J.B. Runyon; 9 ♂, 4 ♀, North Friar’s Bay, 17°16.59'N, 62°40.33'W, 24 May 2017, J.B. Runyon. St. Lucia: 5 ♂, 3 ♀, Savannes, Mangrove Reserve, 0-5 m, 13°45.97'N, 60°54.88'W, 3 May 2009, J.B. Runyon; 3 ♂, Micoud District, Fond Bay at beach, 0-5 m, 13°49.89'N, 60°53.65'W, 8 May 2009, J.B. Runyon (MTEC, USNM).

Distribution.

Widespread, can be found on beaches in the southeastern United States (Florida), Central America (Belize), Ecuador ( Galápagos Islands), and the West Indies (Antigua, British Virgin Islands, Cuba, Dominica, Jamaica, Montserrat, Nevis, St. Kitts, St. Lucia).

Remarks.

Initially, I thought both A. interruptus and A. wirthi Robinson, very similar species ( Robinson and Deyrup 1997), were represented in material from Montserrat. Specimens of A. interruptus show a wide range of intraspecific variability as discussed by Bickel and Sinclair (1997). The large series from Woodlands Beach shows a gradation in characters used by Robinson and Deyrup (1997) to distinguish A. interruptus and A. wirthi (e.g., relative length to width of face, shape of antenna, presence of coppery median band between rows of dorsocentral setae). Dissection and examination of male genitalia of interruptus -morphotype and wirthi -morphotype specimens from Woodlands Beach reveal no obvious differences and both match the illustration in Bickel and Sinclair (1997). Thus, A. wirthi is considered a synonym of A. interruptus .

Asyndetus interruptus adults were seen mostly on open sand almost always near crab holes and most specimens were obtained by quickly placing a net over crab holes to catch adults as they promptly flew out. This species was re-described and illustrated by Bickel and Sinclair (1997).