Simulium (Psilopelmia) ochraceum Walker, 1861

HERNÁNDEZ, LUIS MIGUEL, SHELLEY, ANTHONY JOHN, DE LUNA DIAS, ANTONIO PAULINO ANDRADE & MAIA-HERZOG, MARILZA, 2007, New specific synonymies and taxonomic notes on Neotropical black flies (Diptera: Simuliidae) belonging to the subgenera Chirostilbia Enderlein, Hemicnetha Enderlein, Inaequalium Coscarón & Wygodzinsky, Psaroniocompsa Enderlein and Psilopelmia Enderlein, Zootaxa 1506 (1), pp. 1-80 : 27-28

Simulium (Psilopelmia) ochraceum Walker complex

( Figs. 49, 50 )

Simulium ochraceum Walker, 1861: 332 . NEOTYPE ♀, MEXICO: Chiapas State, Huixtla, Morelos, 30.vi.1985 (A.L. Millest) (BMNH) [Neotype designation by Shelley et al. 2000: 165.]

Simulium bipunctatum Malloch, 1912: 650 . HOLOTYPE ♀, PERU: Rio Charape, 13.ix.1911 (C. H. T. Townsend) (USNM, cat. no. 15305) [Examined.] [Synonymized with S. dinellii Joan by Knab, 1913: 155; revalidated by Coscarón, 1985: 320.] [Synonymy with S. ochraceum by Shelley et al. 2000: 165.]

Simulium antillarum Jennings, 1915: 200 . LECTOTYPE ♂, VIRGIN ISLANDS: St Croix Island, 1.5 miles west of West End, Frederiksted, 24.xi.1913 (A.H. Jennings) (USNM, cat. no. 19997). [Lectotype designation by Stone, 1969: 313).] [Synonymy of S. antillarum with S. bipunctatum by Shelley et al., 1989: 92; synonymy with S. ochraceum by Shelley et al. 2000: 165.]

Simulium scutellatum Lane and Porto, 1940: 192 [In Porto, 1940: 383]. HOLOTYPE ♀ (man-biting), COLOMBIA: Restrepo; 6.i.1935, (S.F.A.) (MZUSP). [Synonymy by Py-Daniel & Moreira Sampaio, 1995.] [Examined.]

Simulium wolcotti Fox, 1953: 138 . HOLOTYPE ♂, PUERTO RICO: Henry Barracks, near Cayey, 1950 (I. Fox) (STMPR). [Synonymy with S. antillarum Jennings by Stone, 1969: 313; synonymy with S. bipunctatum by Shelley et al., 1989: 92; synonymy with S. ochraceum by Shelley et al. 2000: 165.]

Simulium pseudoantillarum Ramírez Pérez & Vulcano, 1973: 379 . SYNTYPES 1♀, 1♂, VENEZUELA: Monagas State, San Antonio de Maturin, [No collection date.] (Ramírez Pérez & Vulcano) (DERM). [Synonymy with S. antillarum by Shelley et al., 1989: 93; synonymy with S. ochraceum by Shelley et al. 2000: 165.]

The female of S. ochraceum was described by Walker in 1861 from the collection of Diptera of W.W. Saunders. No indication of the number of specimens examined was made nor details of the type locality other than Mexico. The complicated taxonomy, distribution, biology and medical importance of this species has been reviewed by Shelley et al. (2000), who also redescribed the female, male and pupa, and designated a neotype for S. ochraceum . However, at that time the authors did not include under the list of synonyms of S. ochraceum the name S. scutellatum , synonymized with S. bipunctatum in Py-Daniel & Moreira Sampaio (1995), because the type material was not available for study. Coscarón (1991) also noted the similarity of S. scutellatum with S. bipunctatum , but declined from making any synonymy until other stages could be obtained for examination. We have now been able to examine the female holotype and one female paratype of S. scutellatum , both housed in the MZUSP, and have the following comments to make. Porto (1940) redescribed S. exiguum and S. subnigrum from specimens collected in Restrepo, Colombia. In this paper the author provided a key to identify eight species of Simulium in which the name S. scutellatum was first published. He keyed out this species by the following characters “…tomentum of mesonotum yellowish; species of small size and developed scutellum…”. Following the rule of the ICZN (1999, article 12, 13) this constitutes the original description of this species. In the same year, Lane and Porto (1940) fully described S. scutellatum based on 16 man-biting females collected in Colombia, Restrepo on 6.i.1935 by S.F.A [=probably Salvador Albani]. They also recorded this species from Juquiá, São Paulo State, but in a later paper Lane & Vulcano (1943) considered this material to belong to another species that they were unable to identify. The female holotype is weakly discoloured, but otherwise in good condition. The paratype is also discoloured and the head is missing (see Material Examined). The holotype has been glued to a card point and the left side of the thorax is partially covered with glue. However, the thorax in both specimens shows a pattern commonly found in populations of S. ochraceum : with light source anterior the thorax is orange with 1+1 pair of submedian silvery white, comma-shaped cunae in anterior third ( Fig. 49 ). With light source posterior to the specimen the thorax is completely orange ( Fig. 50 ). Therefore, we consider S. scutellatum conspecific with S. ochraceum , thus confirming Py-Daniel & Moreira-Sampaio’s (1995) synonymy.

The adults of S. ochraceum are externally similar to S. callidum from which they can only be readily distinguished by the configuration of the pupal gill filaments (see Shelley et al., 2000). Simulium ochraceum s.l. is largely anthropophilic in Central America [see Dalmat (1955) for most comprehensive study of biology of S. ochraceum s.l. in Guatemala] while in Ecuador and in the majority of the Caribbean Islands it is mainly zoophilic, only rarely coming to bite man. It is, however, markedly anthropophilic in the Upper Amazon region of Brazil along the R. Vaupés, but only occasionally bites man farther north in the Amazonia onchocerciasis focus of Brazil and Venezuela. In parts of Guadeloupe and the Galapagos Islands of Ecuador it can also be a biting nuisance, in Guatemala, it is also recorded as biting cats, cattle, chickens, donkeys, dogs, ducks, foxes, goats, horses, mules, pigeons, pigs, sheep, tayras, and turkeys ( Dalmat, 1955). This species is the primary vector of human onchocerciasis in Guatemala and Mexico and may be responsible for sporadic transmission of the disease in the onchocerciasis foci of mainland Ecuador. Shelley et al. (2002) recorded S. ochraceum s.l. from Belize, Brazil, Colombia, Costa Rica, Cuba, The Dominican Republic, Ecuador [including Galapagos Islands], French Guiana, Guatemala, Jamaica, Mexico, Montserrat, Panama, Perú, Puerto Rico, St. Croix and Trinidad.

Figures

PLATE 4. FIGURES 45–58. Colour patterns of the female thorax. For each species first figure is with anterior illumination and second figure with posterior illumination. 45, 46: S. minuanum paratype; 47, 48: S. costaricensis holotype; 49, 50: S. stellatum holotype; 51, 52: S. spinifer holotype; 53, 54: S. spinifer paratype; 55, 56: S. hoffmani lectotype; 57, 58: S. sicuani lectotype.