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Catalogue of the dipterous insects collected at Singapore and Malacca cover

Catalogue of the dipterous insects collected at Singapore and Malacca

Chapter 23: Gen. Chrysops, Meigen.
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About This Book

A systematic catalogue of dipterous insects collected at Singapore and Malacca, listing families, genera, and species with concise morphological descriptions, measurements, and precise collection localities. Entries note diagnostic characters, colouration, and intraspecific variation, and record altitudinal and geographic occurrences when known. Numerous taxa are described as new, accompanied by comparative remarks and occasional figures or plates to aid identification, while brief comments indicate wider distributional links to specimens from neighboring islands and regions.

Fam. TABANIDÆ, Leach.

Gen. Tabanus, Linn.

20. Tabanus univentris, Walk. Cat. Dipt. pt. 1. 151.

The description in the above reference will not well apply to the two following varieties of this species.

Var. 1. Female. Brown. Head testaceous in front and beneath. Thorax with two testaceous stripes. Abdomen ferruginous, tawny beneath and with a dorsal stripe of tawny triangular spots. Legs blackish; femora and tibiæ partly testaceous. Wings dark grey.—Var. 2. Like Var. 1. Abdomen blackish above, with a dorsal stripe of testaceous spots.

Mount Ophir. Inhabits also Borneo.

21. Tabanus partitus, n. s., fœm. Nigricans, subtùs albidus, antennis fulvis apice nigris, thorace cinerascente cano-quadrivittato, abdomine piceo albido-trivittato, pedibus testaceis, femoribus tibiisque apice tarsisque nigricantibus, alis subcinereis.

Female. Blackish; underside and head behind with whitish tomentum. Antennæ dull tawny, black towards the tips; angle of the 3rd joint minute and obtuse. Thorax greyish, with four hoary stripes. Abdomen piceous, with three whitish stripes. Legs testaceous; tarsi and tips of the femora and of the tibiæ blackish. Wings greyish, stigma and veins black; fore branch of the cubital vein simple, nearly straight. Length of the body 6 lines; of the wings 10 lines.

Singapore.

Note.T. rubidus, Wied., is very closely allied to the above species, but may be distinguished from it by the following characters.

T. rubidus. Front with the callus quite entire. Antennæ blackish. Middle stripe of the abdomen composed of triangular spots. Wings greyish.

T. partitus. Smaller. Front with the callus almost interrupted. Antennæ pale tawny, with darker tips. Middle stripe of the abdomen entire, parallel. Wings quite limpid.

Gen. Chrysops, Meigen.

22. Chrysops dispar, Fabr. Syst. Antl. 112. 5.

Mount Ophir and Malacca. Inhabits also Hindostan and Java.