Atrichobrunettia (Polibrunettia) xalapaensis Ibáñez-Bernal, 2009

Ibáñez-Bernal, Sergio, 2009, First record of the genus Atrichobrunettia Satchell in Mexico, with the description of a new species (Diptera, Psychodidae, Psychodinae), Zootaxa 2306, pp. 59-65 : 60-64

Atrichobrunettia (Polibrunettia) xalapaensis Ibáñez-Bernal sp. nov.

( Figures 1−15 )

Male description ( Figs. 1−9 ). Head: rounded in frontal view. Vertex just a little protruded, as long as 3.0X the eye-bridge width, and surface with setae alveoli regularly spaced. Eye-bridge narrow, composed of 3 rows of facets, and separated by 4 facet diameters; interocular suture complete, well sclerotized and inverted Yshaped. Frons between eyes and clypeus with a quadrangular patch of alveoli, that of clypeus with alveoli more spaced than frons ( Fig. 1 ). Antenna as long as 3.0X the head height ( Fig. 1 ) and 2.0X the wing width, scape nearly cylindrical, as long as 2.0X the globular pedicel length ( Fig. 2 ), flagellum with 14 nodiform flagellomeres, 1-12 strongly eccentric flagellomeres, each with a pair of S-shaped ascoids which are longer than the respective flagellomere ( Fig. 2 ); last flagellomere without ascoids but with apiculus ( Fig. 3 ). Palpus about as long as wing width, its apex reaching the level of flagellomere 7 ( Fig. 1 ); palpomere proportions: 1.0: 3.2: 3.2: 4.4; proboscis short, not longer than antennal scape ( Fig. 1 ). Thorax ( Fig. 4 ): with a globular, not pedicelate, allurement organ above the anterior spiracle ( Fig. 5 ). Wing as long as 2.9X its width, with pointed apex; Sc short and not sclerotized; Rs pectinate, radial fork basal to medial fork; R5 ending just a little behind wing apex; CuA2 wide, very close to wing margin and ending apical to the level of medial fork; wing membrane with setae alveoli specially in the apical portion of cells (Fg. 6). Abdomen: terga 1-7 with two bands of setae alveoli, the posterior better defined, tergum 8 with only one band of setae alveoli, tergum 9 (epandrium) nude, with two foramina ( Fig. 8 ); tergum 10 small, triangular in shape with blunt apex; posthypandrial plate somewhat quadrate, sternum 10 pilose with a median thick digitiform projection that ends in a rounded or sometimes somewhat acute apex ( Fig. 8 ). Cercus short, cylindrical with apical portion curved upward; external margin with an sclerotized reinforcement near base, internal margin of cercus with short bristles and apex with more than 20 long tenacula with rounded tips ( Figs. 8, 9 ). Gonocoxite cylindrical, shortest than distiphallus and gonostylus but thinnest than paramere base, with a few small bristles in an external patch; gonocoxal apodemes somewhat broad, fused and forming a bridge and in contact with proximal portion of basiphallus; medial arm broad, posteriorly directed and over the basal portion of distiphallus. Gonostylus somewhat tapered and sinuous with two bristles at apex. Aedeagus with basiphallus nearly as broad as distiphallus, proximal margin truncate between anterior and posterior margin of gonocoxal apodemes-bridge; distiphallus boat-shaped, apically divided at middle; parameres broad at base, lobes with internal margin straight and external sinuous, apically rounded, and ending distad to aedeagus apex ( Fig. 7 ).

Measurements (n=6). Head height: 0.356 ±0.01 (0.34−0.37); proboscis length: 0.073 ±0.006 (0.065−0.080); palpus length: 0.578 ±0.013 (0.56−0.60); antenna length: 1.395 ±0.019 (1.38−1.43); wing length: 1.811 ±0.054 (1.76−1.90); wing width: 0.621 ±0.023 (0.60−0.65); cercus length: 0.114 ±0.009 (0.100−0.125); tergite 9 length at middle: 0.085 ±0.004 (0.08−0.09); gonostylus length: 0.129 ±0.005 (0.120−0.135); aedeagus length: 0.173 ±0.013 (0.160−0.190); gonocoxite length: 0.091 ±0.002 (0.090−0.095).

Female description ( Figs. 10−15 ). Similar to male except for the following characteristics: Antenna short, about 2.5X as long as head height, and reaching the level of flagellomere 11 ( Fig. 11 ); flagellomeres 2-11 only slightly eccentric; a pair of short, arched digitiform ascoids in flagellomeres 1-12 ( Figs. 11, 13 ); flagellomere 13 without internode, partially fused with flagellomere 14, this one pyriform with conical apiculus ( Fig. 12 ). Thorax without allurement organ. Wing about 3.2X as long as wide ( Fig. 14 ). Terminalia: subgenital plate triangular, basal portion with 1+1 patches of alveoli and all surface covered with micropillosity, apical portion only with micropillosity, its apex rounded and ending at the same level than lobes; lobes divergent with rounded apex ( Fig. 15 ); internal genital complex as long as subgenital plate, with large divergent apodemes, its basal portion a pair of ovoid structures with ladder thickening broad margin connected by a stout median bridge with distal bifurcation ( Fig. 10 ).

Measurements (n=4). Head height: 0.357 ±0.015 (0.35−0.38); proboscis length: 0.075 ±0.01 (0.07−0.09); palpus length: 0.592 ±0.018 (0.58−0.62); antenna length: 0.982 ±0.023 (0.95−1.00); wing length: 1.95 ±0.096 (1.85−2.07); wing width: 0.612 ±0.029 (0.58−0.65); cercus length: 0.313 ±0.011 (0.300−0.325); subgenital plate length (with lobes): 0.135 ±0.007 (0.130−0.145); subgenital plate width: 0.225 ±0.01 (0.24−0.26).

Material examined. 12 males, 4 females. Holotype male: MEXICO, Veracruz: Municipality of Xalapa, Xalapa, Coapexpan (19°31´33.24” N, 96° 56´46.31” W, elevation 1378 m). Allotype female: Same data than holotype. Paratypes: 11 males and 3 females with same collection data. All specimens mounted in permanent slides. Holotype, allotype, 7 males and one female paratypes deposited in IEXA, 4 male and 2 female paratypes deposited in LACMNH.

Type locality: MEXICO, Veracruz: Municipality of Xalapa, Xalapa, Coapexpan (19°31´33.24” N, 96° 56´46.31” W, elevation 1378 m).

Etymology. The name xalapaensis refers to the locality in which the species was collected.

Comments. This species clearly belongs to genus Atrichobrunettia because it exhibits the following characters: antenna with 14 flagellomeres, palpomere 1 very short, wings 2.9-3.2 times longer than wide, with undeveloped costal and anal areas, Rs pectinate, radial fork basad to medial fork, R5 ending just behind the wing tip, wing membrane with marginal patches of seta alveoli, male with tergum 9 without setae, and symmetrical aedeagus, and female with internal genitalia complex large, with long divergent apodemes, subgenital plate triangular in outline with relatively large lobes. Atrichobrunettia xalapaensis sp. nov. can be placed in subgenus Polibrunettia because it has antennae composed of 14 flagellomeres, and a wing with an unsclerotized Sc, but differs from all other known species of the subgenus by the form of the male parameres; parameres of all other species are triangular with pointed apex, except in A. pennata Bravo in which they are truncated, and A. bora Bravo in which they have rounded tips. Nevertheless, A. bora has parameres with symmetrical internal and external margins (paddle-shaped), whereas A. xalapaensis has parameres with internal margin straight and external margin sinuous. In addition, A. bora has the distiphallus margins concave, whereas A. xalapaensis has distiphallus margins convex. It is difficult to compare the female with the other species of the subgenus, because only the female of A. longipenis Bravo has been described. It should be noted that the male of Atrichobrunettia xalapaensis sp. nov. has a patch of few small setae in the external margin of gonocoxite and has an eye-bridge separated by 4 facet diameters. These characteristics do not correspond to the description of subgenus Polibrunettia Bravo (2006), and need to be considered in the future.

Atrichobrunettia (Polibrunettia) xalapaensis sp. nov. is an inhabitant of the cloud forest with Liquidambar styraciflua , and Quercus spp. as predominant tree species (1250-2000 m of altitude), and probably of the coffee plantations at high altitudes. Collections outside the cloud forest altitude range have not yet included this species.

Figures

FIGURES 1 − 6. Atrichobrunettia (Polibrunettia) xalapaensis Ibáñez-Bernal, sp. nov., male. 1. Head in frontal view (left antenna and one ascoid of flagellomeres 1 & 2, and both of flagellomeres 3 − 13 not drawn). 2. Antennal scape, pedicel and first two flagellomeres (only one ascoid of each drawn). 3. Apical flagellomeres (ascoids not drawn). 4. Left pleura (partial). 5. Detail of frontal portion of left pleura showing the allurement organ (ao), and stigma (st). 6. Right wing. Figures 2 − 3 at same scale, scales in millimeters.

FIGURES 7 − 10. Atrichobrunettia (Polibrunettia) xalapaensis Ibáñez-Bernal, sp. nov., Figs. 7 − 9 male, Fig. 10 female. 7. Aedeagus, parameres and gonopods, dorsal view. 8. Terga 9, 10, and cerci, ventral view. 9. Cercus showing tenacula, dorsal view. 10. Internal genital complex of female. Figures 7 − 8 at same scale, scales in millimeters.

FIGURES 11 − 15. Atrichobrunettia (Polibrunettia) xalapaensis Ibáñez-Bernal, sp. nov., female. 11. Head in frontal view (left antenna, right palpus and flagellar ascoids not drawn). 12. Apical flagellomeres. 13. Antennal scape, pedicel and first two flagellomeres (only one ascoid of each drawn). 14. Right wing. 15. Subgenital plate, external ventral view. Figures 12 − 13 at same scale, scales in millimeters.