Paratrikona rubescens Blake, 1939

Simões, Marianna V. P., 2017, Revision of the Greater Antilles genus Paratrikona Spaeth, 1923 (Coleoptera: Chrysomelidae: Cassidinae: Dorynotini), Zootaxa 4238 (3), pp. 417-425 : 421-423

Paratrikona rubescens Blake, 1939

(Figs 10–12)

Paratrikona rubescens Blake 1939: 238 (type locality: ‘Jarabacoa, Dom. [inican] Rep. [ublic]’) Paratrikona albomaculata Borowiec, 2009: 567 (type locality: ‘Jarabacoa, Rep. Dominikana’); Sekerka, 2006: 300 (synonymy).

Type specimens. Paratrikona rubescens , holotype (male), pinned: ‘triangle with aedeagus glued [gl, tr] || Jarabacoa | Aug. ’38, Dom. Rep. | 1,500–4,000 ft. | Darlington [w, p, cb] || MCZ | Typ . No | 23636 [w, hw, cb] || Paratrikona | rubescens | type Blake [w, hw, cb] || Jan.–Jun. 2003 | MCZ Image | Database [w, p, bb] || M.C.Z. | Type | 23636 [r, cb, p]’ ( MCZ) . Paratype, pinned: ‘ Jarabacoa | Aug. ’38, Dom. Rep. | 1,500–4,000 ft. | Darlington [w, p, cb] || M.C.Z. | Paratype | 23636 [r, cb, p]’ ( MCZ) . Paratrikona albomaculata , holotype (unsexed), pinned: ‘Rep. Dominikana | 5–7. 5. 2001 | Jarabacoa env. | lgt. Z. Martinová [w, cb, p] || HOLOTYPE | des. L. Borowiec [r, cb, p, bb] || Paratrikona | albomaculata n. sp. | HOLOTYPUS | des. L. Borowiec 2009 [w, p, cb, bb]’ (DBET).

Additional specimens examined (3). DOMINICAN REPUBLIC: Barahona, 1700 m, 22.VI.2015, Carlos Molinari lgt. (1 male, 2 females, SEMC).

Diagnosis. Paratrikona rubescens is readily characterized by the pronotum with large brownish-black Mshaped spot and elytra with red ground color. Males, when alive, present elytra with conspicuous irregularly scattered chalk-white spots, which lose their brightness when dry. Females, whether alive or as dry specimens, have a well-marked semicircular spot around postscutellar tubercle, two large spots on slope and spots on explanate margin.

Morphologically, the closest species to P. rubescens within the genus is P. variegata . Blake (1939) indicated that P. variegata has elytra with deep red color, glabrous, slightly larger, and wider with fewer, coarser punctures and with a postscutellar tubercle higher than in P. rubescens . While I was able to confirm most of these characters, I did not observe pubescence on the elytra in any of the specimens in the series of P. rubescens . This may be due to the age of the specimens. In addition, I observed that P. rubescens has punctuate humeral angle, conspicuous poorly developed humeral ridge, and a postscutellar tubercle in lateral view followed by gradual and uniform slope. In contrast, P. variegata has impunctate humeral angle, humeral ridge absent and postscutellar tubercle in lateral view followed by abrupt, sinuous slope.

Remarks. Blake (1939) described P. rubescens based on two specimens collected in Jarabacoa, Dominican Republic, by P. J. Darlington. The dried male specimen dissected by Blake has elytra deep red with faint white spots around the postscutellar tubercle and on the slope, while the second specimen has a slight trace of white markings close to the postscutellar tubercle only and one at the margin. In the remarks of its description, Blake (1939) indicated that Dr. Darlington observed that when alive, P. rubescens has red coloration with conspicuous white blotches irregularly arranged, however, only a slight trace of the white markings are detectable on dried specimens.

Borowiec (2009) described P. albomaculata based on two unsexed specimens from Jarabacoa, Dominican Republic. He considered the species very distinct from others in the genus, mainly due to its conspicuous bicolor dorsal aspect, by showing elytra with large chalk-white relief forming incomplete ring around postscutellar tubercle and spots on explanate margin. However, Sekerka (2016) considered that both species share puncturation pattern, elytra convexity, and black M-shapped pattern of pronotum, and that the white-chalk mark on the elytra was a character present in both species, but in specimens used to describe P. rubescens it was indicated only slightly. Based on these remarks he considered those specimens to be conspecific and synonymized P. albomaculata with P. rubescens .

During recent fieldwork in the Dominican Republic, I collected two females and one male that fit the description of the former P. albomaculata and P. rubscens , respectively. The females (Figs 16–17) have elytra with strong chalk-white markings, while the male (Figs 18–21) has slightly less distinct marks. However, when both specimens dried, the male lost the white marking and acquired a rather red coloration of the elytra, retaining faint white marks, similar to the holotype of P. rubescens . Based on these observations, I affirm the conclusion of Sekerka (2016) that P. albomaculata is a synonym of P. rubescens and this variation observed by him is actually sexual dimorphism within the species.

Distribution. Dominican Republic (Barahona, Jarabacoa) ( Blake, 1939; Borowiec 2009).