Tiridates mexicanus ( Herrich-Schaeffer, 1837 )

Eger, J. E., 1987, A Review of the Genus Tiridates Stal (Heteroptera: Pentatomoidea: Scutelleridae), The Florida Entomologist 70 (3), pp. 687-716 : 348-349

Tiridates mexicanus ( Herrich-Schaeffer, 1837)

Pachycoris mexicanus Herrich-Schaeffer, 1837, p. 3 , fig. 343; Germar, 1839, p. 89. Pachycoris flavicinctus Herrich-Schaeffer, 1837, p. 8 , fig. 351; Germar, 1839, p. 103. Agonosoma mexicanum: Dohrn, 1859, p. 4.

Agonosoma flavocinctum: Dohrn, 1859, p. 4.

Agonosoma mexicana: Walker, 1867, p. 60.

Agonosomaflavicincta: Walker, 1867, p. 60.

Tiridates flavocinctus: Stal, 1867, p. 494.

Tiridates mexicanus : Stal, 1870, pp. 13- 14 ( P. flavicinctus listed as junior synonym); Distant, 1880, p. 19 (synonymy); Uhler, 1886, p. 2 (synonymy); Distant, 1889, p. 313; Lethierry and Severin, 1893, p. 35 (synonymy); Schouteden, 1904, p. 69, pl. 4, fig. 13 (synonymy); Kirkaldy, 1909, p. 278.

Tiridates flavicinctus : Kirkaldy, 1909, p. 278, 365.

Length of body 12.5- 14.8. Head: 3.2-3.6 long, 3.8-4.4 wide, dark brown to black with red to yellow markings usually present at least laterally and frequently most of dorsal surface red to yellow. Antennae dark brown to black, first 1 or 2 segments orcasionally yellow to red; length of segments 1-5: 0.8- 1.0; 0.6-0.8; 0.7-0.9; 1.4- 1.6; 1.8-2.3. Rostrum brown to black, segments 1-2 frequently yellow to red; apex reaching 2nd to 3rd visible abdominal sternite.

Thorax: pronotum broader than long (6.8-8.2 wide, 4.1-4.9 long), dark brown to black with yellow to orange vittae along anterior, antero-, and posterolateral margins and with median longitudinal vitta; vittae frequently reduced or expanded to cover entire pronotum. Dark brown submarginal maculae frequently present in marginal vittae. Thoracic venter typically dark brown to black, except following red to yellow structures: coxae and large macula on adjacent pleura, lateral margins of pro-, meta-, and occasionally mesopleura, margin of prostethus, posterior border of metapleura and portions of evaporative area on metapleura. Legs dark brown to black except basal 2/3 to 5/6 of femora usually orange to red and tibiae infrequently with yellow or red median band. Ostiolar rugae 0.4-0. 7 long; distance from ostiole to metacoxae 1.3- 1.6, distance from ostiole to anterolateral corner of metapleuron 1.8-2.3. Scutellum 7.4-8.8 long, 6. 7- 7.9 wide; typically bordered on all sides by broad yellow vittae and with median transverse vitta, vittae frequently reduced or absent or expanded to cover nearly entire scutellum. Fovea in each basal angle of scutellum and 2 small maculae on anterior border dark brown to black, maculae absent in specimens lacking colored vitta on anterior margin.

Abdomen: venter orange to red with black markings as follows: basal transverse vitta on first to third visible sternites, broad lateral longitudinal vitta (this vitta frequently broken into series of maculae), broadly oval macula near posterior limit of last sternite, 3 to 6 smaller maculae on sternites 4 to 6. Abdominal venter rarely entirely dark brown to black or with basal red to yellow macula on 2nd to 5th visible segments. Mid-ventral length of visible abdominal sternites 2-6: males 0.7-0.8, 0.7-0.9, 0.7-0.9, 0.6-0.7, 3.0-3.3; female 0.8-1.0, 0.9, 0.8- 1.0, 0.8-0.9, 2.6-2.9.

Apices of both arms of each pygophoral process narrowly rounded ( Fig. 19 ). Parameres and proctiger as in Figs. 17 and 18 . Theca relatively short, without distinct lobes ( Figs. 15, 16 ). Thecal processes broad basally from dorsal aspect, narrowing apically to hatchet-shaped apices. Vesica relatively broad, angled ventrad and curving caudad.

Posterior lobe of each first gonocoxa directed mesad and cephalad ( Fig. 22); anterior lobe with relatively broad, moderately sclerotized band along posterior margin. Plates on floor of genital chamber strongly sclerotized, broadly concave, anterior and mesial margins enlarged; narrowly separated mesially ( Fig. 25 ).

Types: Apparently lost.

Distribution: South Mexico, states of Chiapas, Guerrero, Jalisco, Michoacan, Morelos, Nayarit, Oaxaca, and Veracruz.

Comments: There appear to be 3 color morphs of T. mexicanus , all of which are apparently sympatric and all of which have been collected together in series. Two of these morphs were figured by Herrich-Schaeffer (1837) and described as Pachycoris fiavicinctus and P. mexicanus . I've seen only males of the former and both sexes of the latter. A third morph is almost entirely black ventrally and is black dorsally with red markings as follows: lateral band on head, anterior margin of pronotum, vittae along lateral margins of pronotum and scutellum (these relatively thin and frequently broken), submarginal vittae along lateral margins of pronotum, median longitudinal vitta on pronotum, and median transverse vitta on scutellum. Specimens of this morph consisted entirely of females.

Two small black maculae located just mesad of the fovea on the anterior margin of the scutellum were always present in specimens of the first two morphs (the anterior margin of the third morph was entirely black). No such maculae were present in specimens of T. rubrocinctus .

Figures

Figs. 15-20. Tindates mexicanus. 15.) Aedeagus, dorsal aspect; vesica (V); thecal process (TP). 16.) Aedeagus, lateral aspect. 17.) Proctiger, caudal aspect. 18.) Right paramere, lateral aspect. 19.) Genital cup, caudal aspect, omitting parameres and proctiger; anterior lobe of pygophoral process (A); posterior lobe of pygophoral process (P). 20.) Genital cup, caudal margin, lateral aspect. Dimensional lines equal 1.0 mm.

Figs. 21-22. Female genital plates; first gonocoxae (Gxl); second gonocoxae (Gx2); eighth paratergites (Pt8); ninth paratergites (pt9); sclerotized plates on floor of genital chamber (SP); 21.) Tiridates rubrocinctus rubrocinctus. 22.) T. mexicanus.

Figs. 23-26. 23-25. Sclerotized plates in floor of genital chamber. 23.) T. rubrocinctus rubrocinctus. 24.) T. rubrocinctus schaffneri. 25.) T. mexicanus. 26.) T. rubrocinctus rubrocinctus, spermatheca and related structures; sclerotized groove in floor of genital chamber (SG); dilation of spermathecal duct (D); proximal flange of spermathecal pump (PF); distal flange of spermathecal pump (DF); spermathecal bulb (B). Dimensional lines equal 1.0 mm.