Trichomyia brevitarsa (Rapp, 1945)

(Figs. 2–16)

Psychoda brevitarsa Rapp, 1945: 310, fig. 3 (as female). Type­locality: Panama, Canal Zone, Barro Colorado Island. Holotype male: AMNH. Additional references: Fairchild 1951: 17; Duckhouse 1973: 15.

Trichomyia maldonadoi (Vargas), 1953: 128, plate III, figs. 8–11 (as Eubonetia). Type­locality: Mexico, Chiapas, Palenque, margins of the Chacamac River, light trap. A. Dampf, col. Holotype female (slide, Canada balsam): InDRE (PsT­87006). Additional references: Satchell 1956: 148, 155; Duckhouse 1973:5 (neotropical Cat.); Ibáñez­Bernal 2000:625 (Mexican Psychodidae list). Syn. nov.

Trichomyia brevitarsa (Rapp): Duckhouse 1974: 61, figs. 24–29 (redescription, new combination). Additional references: Quate 1996: 8, figs. 1 g –h (as T. brevitarsis Rapp [sic!]); Quate 1999: 416 (specimens resembling T. brevitarsis Rapp [sic!] and discussion).

Trichomyia (Opisthotrichomyia) brevitarsa (Rapp): Bravo 2001:50 (as subgenotype).

All male specimens of Trichomyia from Yucatan over four years of systematic Malaise trap collections in the Biosphere Reserves of Ria Lagartos and Ria Celestun fit with the description of T. brevitarsa (Rapp), while female specimens conform to T. maldonadoi (Vargas) . Collections in Oaxaca and Campeche gave the same taxonomic result. The geographical and temporal concordance of the male and female specimens, as well as some commonly held morphological characteristics show that T. maldonadoi should be synonymized with T. brevitarsa .

Male diagnosis (Figs. 2–9). Duckhouse (1974) adequately redescribed the male of this species. Quate (1994) sketched the male terminalia not only in lateral, but also in dorsoventral view. Head (Fig. 2): Palpus with 4 palpomeres, the first and second just separated by a thin articular membrane. Palpomeres 1 and 2 each with a compact group of sensorial rods, that of palpomere 2 originating from a shallow sensory pit (Fig. 3). Antennal flagellomeres fusiform and symmetric, each with a pair of long curved ascoids (Figs. 2, 4 and 5). Wing as figured (Fig. 6). Terminalia (Figs. 7–9) with gonostylus ventrally articulated to gonocoxite, with its apex as a very sclerotized, curved, mesally directed spine (Figs. 7, 9). Basiphallus long and depressed (Figs. 7, 9). Surstylus and tergite 10 as figure 8.

Measurements. Head height: 0.307 ±0.037 (0.27–0.36) n=4; head width: 0.415 ±0.036 (0.39–0.47) n=4; palpus length: 0.157 ±0.015 (0.14–0.17) n=4; antenna length: 1.15, n= 1; wing length: 1.397 ±0.082 (1.35–1.52) n= 4; wing width: 0.527 ±0.053 (0.47–0.60) n= 4; R2+3+R4: 0.22 ±0.021 (0.20–0.25) n=4; R2+3: 0.572 ±0.066 (0.52–0.67) n=4; Gonocoxite length: 0.115 ±0.005 (0.11–0.005) n=4; gonostylus length: 0.067 ±0.005 (0.06–0.07) n=4, surstylus length: 0.15 ±0.008 (0.14–0.16) n=4.

Female description (Figs. 10–16). Head nearly rounded in frontal view, 1.3 times as wide as high. Front and vertex as in male, with the three pairs of transparent sensillae, all surface regularly covered with setae insertions, an irregular row of large hairs above the margin of each eye, and a patch of large setae between the antennal insertions (Fig. 11). Antenna with 13 more or less recessed flagellomeres (Fig. 11), each with a pair of rod­like simple ascoids extending beyond the respective flagellomere tip; apical flagellomere with an oval apiculus (Figs. 12, 13); scape similar in length to pedicel (Fig. 13). Palpus with 4 palpomeres, palpomere 1 and 2 partially fused, each with a patch of sensory rods, but not clearly originating from a pit as in male. Palpus formula: 1.0: 0.83: 1.0: 1.16 (Fig. 10). Anepisternum with setae alveoli separated by more than one diameter. Wing 3X as long as wide. Sc fused distally with R1; a vein­like infuscation between Sc and C, but without setae; Rs originating at same level of humeral infuscation, giving rise to R2+3+R4 at same level of the apex of Sc; radial fork before middle of wing; R5 ending behind the rounded apex of wing. M2 base obsolete, the median fork basad to radial fork. CuA2 long, extending beyond medial fork and ending a little before the radial fork. All veins barely infuscated near the base of wing, especially radial veins. Proportion of R2+3+R4: R2+3= 1.0: 3.2 (Fig. 14). Terminalia as figured (Figs. 15, 16); subgenital plate oval, prolonged in the middle as a quadrate lobe, the distal margin trilobate and setose (14–16 setae), the median projection larger than laterals (Fig. 16). Internal sclerotizations in the form of two external ear­shaped laminae and a pair of internal rods finely striated on inner margin, both structures wider at proximal end, with an external sclerotization near apex connecting the subgenital plate, proximally in contact with the plate that gives rise to the pair of spermathecal ducts; basal spermathecal apodeme “T”­shaped (Fig. 15). Spermathecal duct annulated, slightly increasing in diameter towards apex; duct finishing in a cylindrical structure, which is reinforced by a well sclerotized ring and a dome­shaped structure (Fig. 15). Tergite 9 nude. Cercus short and nearly rounded in lateral view.

Measurements. Head high: 0.277 ±0.17 (0.26–0.30) n=4, wide: 0.327 ±0.012 (0.31– 0.34) n=4; Antenna length: 0.845 ±0.005 (0.84–0.85) n=2; Palpus length: 0.16 ±0.01 (0.15–0.17) n=2; wing length: 1.327 ±0.061 (1.29–1.42) n=4, width: 0.497 ±0.028 (0.46– 0.52) n=4; R2+3+R4 length: 0.187 ±0.022 (0.17–0.22) n=4; R2+3: 0.54 ±0.043 (0.50–0.60) n=4; subgenital plate length: 0.122 ±0.005 (0.12–0.13) n=4, width: 0.175 ±0.017 (0.15– 0.19) n=4; cercus length: 0.10 ±0.011 (0.09–0.11) n=4.

Material examined (as labeled): 18 males, 17 females. México, Yucatán, Municipio Celestún, Rancho Loma Bonita, km 16 carretera Celestún­Kinchil, 5­Sept­1995 (selva baja caducifolia espinosa), Malaise trap at night, H. Huerta, R. Paz C. Navarro and P. Manrique, cols. (1 male, 1 female); 7­Sept­1995 (petén) (1 male, 1 female); 6­Dec­1995 (petén) (1 male); Municipio Tizimín, Res. Esp. Biosfera Ría Lagartos, 1 km al N de la Estación, Ojo de Agua (petén), Malaise trap at night, H. Huerta and C. Navarro, cols. (1 female); Municipio Tizimín, entrada a Zac­Boo, 25­Nov­1995 (selva baja caducifolia espinosa) Malaise Trap at day, H. Huerta, C. Navarro and R. Paz, cols. (1 female); 28­Nov­ 1995 (2 males, 8 females); State of Oaxaca, Tuxtepec, 7/ 8­March­1998, margin of river, Malaise trap, H. Huerta and C. Pérez, cols. (12 males, 4 females); State of Campeche, Mpo. Calakmul, Ruinas de Calakmul, 26­enero­1999, trampa de luz CDC. R. Paz, E. Romero y E. Uc Ucan, cols. (1 male, 1 female). All specimens deposited in IEXA, Veracruz, Mexico.

Additional material examined (as can be read from the label): “ Holotype female (6617), Eubonetia maldonadoi, A. D. (abbreviations of Alphonse Dampf) pp. 6­III­1947. Palenque, Chiapas, lámpara trampa a orilla del Río Chacamac”. Canada balsam, InDRE (PsT­87006).

Comments. The only difference presented by the male specimens studied here with the redescription of Duckhouse (1974) is the position of the sensory rods of the palpus. Duckhouse indicated that they originate from a pit in the antepenultimate palpus segment, but the specimens from Mexico show in addition to the sensory rods, others that originate from the basal palpomere not from a pit (Fig. 3) that are difficult to see.

Trichomyia brevitarsa (Yucatan) Trichomyia maldonadoi

Structure Females (n=4) Holotype female

Mean Smallest Largest

Trichomyia maldonadoi was originally described as a species of the genus Eubonetia based on one female specimen collected by Dr. A. Dampf using a light trap in the margins of the Chacamac River, Palenque, Chiapas, Mexico. The original description by Vargas (1953) is concise, but the illustrations were from bad photographs that do not show the important characteristics. The holotype specimen has no morphological differences from the characteristics presented for the female of T. brevitarsa, as can be see in figures 17–20, and their measurements are not significantly different (Table 1).