Culicoides (Haematomyidium) debilipalpis Lutz, 1913

Huerta, Rodríguez, Ana M., William L. Grogan, Jr. & Ibáñez-Bernal, Sergio, 2012, New records of biting midges of the genus Culicoides Latreille from Mexico (Diptera: Ceratopogonidae), Insecta Mundi 2012 (211), pp. 1-20 : 3-5

Culicoides (Haematomyidium) debilipalpis Lutz

Culicoides debilipalpis Lutz, 1913: 60 ( Brazil) ; Macfie 1948: 86 ( Mexico, Chiapas).

Culicoides (Haematomyidium) debilipalpis: Vargas 1960: 42 (in list of New World species in subgenus Haematomyidium ).

Culicoides (Oecacta) debilipalpis: Wirth 1965: 129 (in Nearctic catalog; distribution); Wirth 1974: 29 (in New World Catalog south of the USA; distribution).

Culicoides ichesi Ronderos and Spinelli, 1995: 77 ( Argentina) .

Culicoides khalafi Beck, 1957: 104 (Florida, USA).

Discussion. Under their distribution section for C. debilipalpis, Vitale et al. (1981) stated “A common species in the southeastern U.S. from Maryland and Kentucky to Florida and Louisiana; absent in Texas, Mexico, and the West Indies; present in Central and South America south to Argentina. It is replaced in Texas and Mexico by C. eadsi Wirth and Blanton and in West Indies by C. hoffmani Fox. ” More recently, Borkent and Spinelli (2007) listed this species distribution as “Widespread from the USA (Maryland, Kentucky, Nebraska south to Louisiana and Florida), Guatemala and Belize to Argentina.” Whereas, Borkent and Grogan (2009) listed it from “…Honduras south to Argentina. Macfie (1948) reported C. debilipalpis in Mexico from Chiapas based on specimens collected during 1935 in the collection of Alfonso Dampf. However, we have been unable to confirm these records because we were unable to locate his specimens in CAIM. We provide records of C. debilipalpis from Mexico based on specimens in the FSCA collected in Veracruz and Yucatán that were identified as this species by Willis Wirth. Confirmed Mexico record.

Spinelli and Wirth (1986) considered C. debilipalpis a junior (subjective) synonym of C. lahillei (Iches) based on overall similarities of specimens of C. debilipalpis with the original description and illustrations of C. lahillei . Soon after, Ronderos and Spinelli (1997) examined a single female from the type series of C. debilipalpis collected from the Brazilian states of São Paulo and Formosa in the Instituto Oswaldo Cruz, Rio de Janeiro, Brazil. They noted that the palpus of this specimen was illustrated by Costa Lima (1937) who pointed out that it was collected 30 January 1918 from Salto de Iguaçu, Paraná, Brazil. Ronderos and Spinelli (1997) concluded that Costa Lima (1937) incorrectly assumed that this specimen was an example of C. debilipalpis , and, that it agreed with Iches’ (1906) description and illustrations of C. lahillei . Therefore, Spinelli and Ronderos resurrected C. debilipalpis from synonymy with C. lahillei , and noted several morphological differences between females of C. lahillei and C. debilipalpis . For example, C. lahillei has a very slender 3 rd palpal segment (palpal ratio 3.70-4.00 vs. 2.00-2.60 in C. debilipalpis ), a greater number of mandibular teeth (18-22 vs. 14-17 in C. debilipalpis ), a pale halter (dark in C. debilipalpis ) and the wing lacks macrotrichia in cell m 2 and anal cell (macrotrichia present in both cells in C. debilipalpis ). Spinelli and Ronderos also provided illustrations of the male genitalia of both species and noted several features in C. lahillei that differ from males of C. debilipalpis . For example, males of C. lahillei have much shorter apicolateral processes, the aedeagus has a much lower basal arch, the midportion of the parameres lack a subapical ventral lobe and the apices only have an indistinct fringe of barbs, sternite 9 has a deeper, broader caudomedian excavation and the ventral root of the gonocoxite is much broader basally. Finally, it is also worth noting that during the brief period that both species were considered conspecific, the Neotropical Wing Atlas ( Wirth et al. 1988; fig. 179) featured a photograph of a female wing of C. lahillei , which is actually a specimen of C. debilipalpis from Panama.

We initially identified female specimens in ethanol of the related, very similar species, C. eadsi Wirth and Blanton from Mexico in the CAIM collection. The type series of this species was collected from tree holes in Cameron County, Texas in the extreme southeastern tip of this state just north of the Rio Grande River. Wirth and Blanton (1971) also identified 58 females and 8 males of C. eadsi from Nayarit, San Luis Potosí, Sonora and Yucatán, Mexico, but they did not designate these paratypes. More recently, Borkent and Spinelli (2000, 2007) included Cuba, Guatemala and Florida, USA within the geographic range of this species. The aedeagus of male C. eadsi has a broad distal portion with a truncate apex that bears five sharply pointed sclerites and the median sclerite is much broader than the two lateral ones on either side. By contrast, the distal portion of the aedeagus of male C. debilipalpis is much longer, more slender with a narrow pointed apex.

However, we discovered problems with several published morphometric differences between females of these two species. For example, Wirth and Blanton (1971) gave palpal ratio (PR) 2.80, costal ratio (CR) 0.57 and proboscis/head (P/H) ratio 0.83 for C. eadsi and these values were repeated in the Nearctic ( Wirth et al. 1985) and Neotropical ( Wirth et al. 1988) wing atlases of Culicoides . In their “The Sand Flies ( Culicoides ) of Florida” Blanton and Wirth (1979) listed the following for C. debilipalpis: PR 2.20, CR 0.65 and P/H 1.00, and, these values were repeated in the Nearctic and Neotropical wing atlases. Based on the illustration of the female palpus of C. eadsi in Wirth and Blanton (1971), we calculated 2.33 for PR, which is considerably lower than 2.8 they reported. We then measured five female paratypes of C. eadsi that yielded the following: PR 2.44-2.50, CR 0.56-0.58 and P/H 0.81-0.90. We also measured 20 female C. debilipalpis from the USA from Florida (n=9), Georgia (n=5), Maryland (n=4), Alabama (n=1), and Virginia (n=1) and 30 females from Mexico (n=8), El Salvador (n=10), Honduras (n=10) and Panama (n=2) and obtained the following means and ranges for these 50 specimens: PR 2.40 (1.90- 2.82), CR 0.58 (0.55-0.60) and P/H 0.91 (0.69-1.01). It is now obvious that the CR of female C. debilipalpis is much lower than 0.65 as listed by Blanton and Wirth (1979), Wirth et al. (1985) and Wirth et al. (1988). We suspect that the values of this character were inverted and the true value for this character in Blanton and Wirth (1979) was probably meant to be 0.56. It is also apparent that none of these three morphometric characters adequately distinguish females of both species and, therefore, we have not included any new records of C. eadsi from Mexico herein.

New records. Veracruz, Fortin , 17 May 1964, F. S. Blanton, 1 female ; same data except 30 August 1964, 1 male ; same data except Fortin de la Flores, 23 July 1964, 3 females ( FSCA). Yucatán, Merida, 31 July 1964, P. J. Spangler, light trap, 5 females ( FSCA). New country record .

Species Unplaced to Subgenus