Placukorna ipsa Santiago-Jimenez

Santiago-Jimenez, Quiyari J. & Santiago-Navarro, Rosny, 2016, A new genus and species of Placusini from a high mountain in Mexico, ZooKeys 640, pp. 45-57 : 49-53

Placukorna ipsa Santiago-Jimenez sp. n. Figs 1, 2, 3-14

Type locality.

México: Veracruz, Perote, Ejido Agua de los Pescados, 3090 m a.s.l., 19°31'30"N, 97°07'00"W, mixed pine forest, Lindgren trap # 14, 08-15.V.2015, P. Domínguez, C. Ruíz and R. Santiago.

Type material.

Holotype, male, pinned. Original label: “México: Veracruz, Perote, Agua de los Pescados. B. Pino mixto, 19°31'30"N, 97°07'00"W, 3086 m, tr. Lindgren #14, 08. V– 15.V.2015, P. Domínguez, C. Ruíz, R. Santiago"/ “MUZ-UV-COL-00003446” / HOLOTYPE Placukorna ipsa Santiago-Jiménez, 2016" [red label].

Other material.

Paratypes, same data as holotype except for: tr. de cruz # 6 (1 specimen ♂); same data except for: tr. de cruz # 8 (1 specimen ♀); same data except for: tr. de cruz # 7, 20. III– 27.III.2015 (1 specimen on slide ♂); same data except for: tr. Lindgren # 11, 27. III– 03.IV.2015 (6 specimens: 2 ♀ on slide; 2 specimens ♂ and 2 specimens ♀); same data except for: tr. Lindgren # 13 (1 specimen ♂); same data except for: tr. Lindgren # 14 (2 specimens: 1 specimen ♀ and 1 specimen ♂); same data except for: tr. de cruz # 6 (2 specimens ♂); same data except for: tr. de cruz # 7 (2 specimens ♀); same data except for: tr. de cruz # 9 (1 specimen ♂); same data except for: tr. Lindgren # 14, 10. IV– 17.IV.2015 (1 specimen ♂); same data except for: tr. de cruz # 8, 17. IV– 24.IV.2015 (2 specimens: 1 specimen ♂ and 1 specimen ♀); same data except for: tr. Lindgren # 13 (1 specimen ♀); same data except for: tr. de cruz # 7, 24. IV– 01.V.2015 (1 specimen ♂); same data except for: tr. Lindgren # 12 (1 specimen ♀); same data except for: tr. Lindgren # 14 (1 specimen ♂); same data except for: tr. de cruz # 9, 01. V– 08.V.2015 (2 specimens ♀); same data except for: tr. Lindgren # 12, 15. V– 22.V.2015 (1 specimen ♂). All specimens deposited in MUZ-UV under numbers MUZ-UV-COL-00003447 to 00003473 [yellow label].

Diagnosis.

Although for the moment it is the only one known species to the genus, it is distinguished by the following combination of characters: body length 2.5-3.0 mm; head and pronotum dark brown and abdomen black; apical half or apical third of sternites III-VI reddish brown; elytra dark brown to black; coxae dark brown to black; metatrochanter and metafemur dark brown or yellowish brown, remaining legs yellowish brown; antennomeres 1-11 dark brown; surface of tergites and sternites III–VII with reticulate microsculpture, less evident on tergites III–IV; tergites III–VII with basal impression, III–V almost straight, VI posteriorly slightly curved, VII posteriorly evidently curved; tergite VI with a protuberance on each side of midline; spermatheca with small and approximately spherical capsule, median portion of spermathecal stem (duct) narrowly U–shaped, and posterior portion also U–shaped, with accessory gland; median lobe with moderately large bulbus, tubus almost straight, internal sac of median lobe with evident spinules, apex blunt in lateral view, with short compressor plate (less than half of median lobe), basal ridge convex and pointed; flagellum short, without coils in bulbus; process of crista apicalis long, almost straight and parallel to median lobe, rounded at the apex.

Description.

Body length 2.5-3.0 mm. Head and pronotum dark brown and abdomen black; apical half or apical third of sternites III-VI reddish brown; elytra dark brown to black; coxae dark brown to black; metatrochanter and metafemur dark brown or yellowish brown, remaining legs yellowish brown. The apical edge of tergite III can be reddish.

Head. Dorsal surface without impression, protuberance or carina on disc (Fig. 4). Antennomeres 1-11 dark brown. Antennomeres 1-2 very long, 3 long, 4-10 transverse, and 11 long (Fig. 3).

Mouthparts. As described for the genus.

Thorax. As described for the genus.

Abdomen. As described for the genus. Other conspicuous characters are: surface of tergites and sternites III–VII with reticulate microsculpture, less evident on tergites III–IV; tergites III–VII with basal impression, III–V almost straight, VI posteriorly slightly curved, VII posteriorly evidently curved, and tergite VI with a protuberance on each side of midline.

Secondary sexual structures. There are differences between the sexes in the shape of sternite VIII and the number of macrosetae on it (Figs 8, 9). No other visible secondary sexual characters were found.

Female. Spermatheca with small and approximately spherical capsule, median portion of spermathecal stem (duct) narrowly U–shaped, and posterior portion also U–shaped, with accessory gland (Fig. 13).

Aedeagus. Median lobe with moderately large bulbus, tubus almost straight, internal sac of median lobe with evident spinules, apex blunt in lateral view, with short compressor plate (less than half of median lobe), basal ridge convex and pointed; flagellum short, without coils in bulbus (Fig. 12). Process of crista apicalis long, almost straight and parallel to median lobe, rounded at the apex (Fig. 12). Paramere with anterodorsal margin of paramerite with prominent sensory pores present beneath the velar sac (Fig. 14); hinge zone of paramerite evident, extended from dorsal surface to near articulation between condylite and paramerite; apical process of paramerite clearly articulated anterior to edge of velum; condylite with row of sensory pores; velum short (less than half length of paramere).

Remarks.

Placukorna ipsa is the only described species in the genus. The characters that could be useful at the species level are the shape of the aedeagus, spermatheca, and impressions and protuberances on the abdomen as described above.

Some characters that vary among the specimens collected are: protuberances on each side of midline of tergite VI are inconspicuous to prominent, one specimen had a raised midline from tergite III–VI, and the horn of tergite VIII is as long as tergite VII or tergites VI–VII together.

Etymology.

As the specimens were found associated with Scolytinae of the genera Ips DeGeer and Pseudips Cognato, the name makes reference to Ips from Greek “ἴψ” (meaning sort of worm), with Greek ending “a”.

Gender.

Neuter.

Habitat.

Specimens of Placukorna are possibly living in galleries of Ips and Pseudips associated with different Pinus species of the mixed pine forest ( Pinus pseudostrobus predominating) where they were collected. Specimens were collected using traps baited with a mix of semiochemicals (ipsenol, ipsdienol and lanierone), in which more than 180 specimens of Ips (94) and Pseudips (91) were also collected. The semiochemicals are commonly used in those traps to capture bark beetles (Scolytine), therefore, an association of specimens of Placukorna with Ips and Pseudips is plausible.

Distribution.

Placukorna ipsa sp. n. is known from the type locality in the central region of Veracruz, Mexico. Twenty-eight specimens of Placukorna ipsa sp. n. were captured by handmade intercept traps for bark beetles primed with the semiochemicals mentioned above, in mixed pine forest. The locality Agua de los Pescados is 3090 m a.s.l. on the northeast face of the Cofre de Perote, Veracruz, Mexico (Fig. 15).