Centroptella (Chopralla) colorata Soldán, Braasch

Kluge, Nikita J., 2021, Review of Centroptella Braasch & Soldán 1980 (Ephemeroptera, Baetidae), Zootaxa 5054 (1), pp. 1-144 : 138-141

3.7. Centroptella (Chopralla) colorata Soldán, Braasch & Luu-Tham-Muu 1987

( Figs 673–686 )

Centroptella colorata Soldán, Braasch & Luu-Tham-Muu 1987: 346 (larva, ♀ subimago); Kluge, Godunko & Svitok 2020: 121 (larva).

Chopralla colorata: Tong & Dudgeon 2003: 17 ;

Bungona (Chopralla) colorata: Salles, Gattolliat & Sartori 2015: 104 .

Centroptella (Chopralla) fusina (Tong & Dudgeon 2003) syn. n.:

Chopralla fusina Tong & Dudgeon 2003: 17 (larva, ♂ & ♀ imagines);

Bungona (Chopralla) fusina: Salles, Gattolliat & Sartori 2016: 104 ; Shi & Tong 2019: 581 (larva);

Centroptella fusina: Kluge, Godunko & Svitok 2020: 92 .

Material examined. Holotype of C. colorata : immature male larva of last instar (see Kluge et al. 2020). Holotype and paratypes of C. fusina : photos provided by Xiaoli Tong.

Distribution. Vietnam and Hong Kong.

Comments: type specimens of C. colorata . Originally, C. colorata was described as larvae and female subimago extracted from mature larva ( Soldán et al. 1987). At present, only the holotype, male larva of last instar, is retained, wile the paratypes are lost.

According to the original description, «posterior margin of terga ... IV–X with stout pointed triangular teeth arranged into a simple row» ( Soldán et al. 1987: 346); however, in the holotype tergum IV has no denticles (teeth), and the denticles are present beginning from the tergum V ( Fig. 682 ). Structure of tergum X was not reported in the original description; the holotype has one pair of large denticles on angles of its posterior projection ( Fig. 683 ).

The combination of larval characters of C. colorata (right prostheca V-shaped, denticles on posterior margins of abdominal terga V–IX, tenth abdominal tergum with one pair of large denticles only) agrees with that of the new Indian species C. ghatensis sp. n. Both larvae and winged stages of C. colorata well differ from C. ghatensis sp. n. by absence of hypodermal coloration on abdominal terga. The holotype of C. colorata examined by me has very contrasting brown markings on cuticle of thoracic terga and pleura and on abdominal terga ( Fig. 681 ), but its hypoderm under cuticle is entirely colorless. According to the original description, the female subimago extracted from larva had «Body pale whitish .... Abdominal terga without markings» ( Soldán et al. 1987: 346). This means that the absence of hypodermal coloration observed in the larva kept in alcohol during 36 years was not caused by some selective depigmentation of the hypoderm (with cuticular pigmentation well preserved), but was initially inherent to these specimens. In contrast to C. colorata , male and female larvae and winged stages of C. ghatensis sp. n. have very intensive and contrasting hypodermal coloration of abdominal terga, which have not become paler after seven years preservation in alcohol.

Comments: type specimens of C. fusina . C. fusina was described from Hong Kong based on 4 larvae, one male and one female imagines and one male subimago, with female larva designated as the holotype. Both imagines and the subimago reported in the original description, were individually reared from larvae, and their subimaginal exuviae were preserved and examined, but this fact was not reported in the original description (personal communication by Xiaoli Tong). On the drawing of male imaginal genitalia given in the original description (Tong & Dudgeon 2003: fig. 16), terminal segments of gonostyli are somewhat longer than on the photo of the slide from which this drawing was done ( Fig. 684 ).

Larva of C. fusina was said to differ from C. colorata in the color pattern of pronotum and mesonotum and in three morphological characters as follows ( Shi & Tong 2019):

(1) «The prostheca of right mandible bifurcated and plumose ... (vs. the right prostheca plumose but not bifurcated in B. colorata )». In the original description of C. colorata the prostheca is really characterized as «plumose but not branched», but figured as bifurcate with branches brought together ( Soldán et al. 1987: fig. 17).

(2) «Tergites V–X with acute triangular spines on posterior margins ... (vs. tergites IV–X with such spines in B. colorata )». This statement was based on the original description of C. colorata , which disagrees with the holotype structure (see above). Actually both the holotype of C. colorata and the type specimens of C. fusina have rows of denticles (i.e. spines, or teeth) on posterior margins of abdominal terga V–IX and one pair of large denticles on posterior projection of tergum X ( Figs 682–683 , 685–686 ).

(3) «Gill I less than 4 times as long as wide, and other gills relatively broad, much less than 2.5 times as long as wide) ... (vs. in B. colorata , gill I more than 5 times as long as wide and other gills narrow-elongate and at least 2.5 times as long as wide)». Actually, tergalii (so called «gills») of C. colorata never had been figured, and this comparison was based on the wordily description only, which stated that «gill 1 ... more than 5 times longer than broad; gills 2–5 apically rounded or bluntly pointed ... about 2.5–3.5 times as long as broad» ( Soldán et al. 1987: 346). Actually, tergalii of the holotype of C. colorata are wider than reported in the original description ( Figs 673–679 ).

Color pattern of pronotum and mesonotum somewhat differs in the original description of C. colorata ( Soldán et al. 1987: fig. 26), on the holotype ( Fig. 681 ) and in the redescription of C. fusina ( Shi & Tong 2019: figs 52, 59), that can be explained as individual variability.

Based on this, I propose the following subjective synonymy: C. colorata = C. fusina syn. n.

Figures

FIGURES 673–683. Centroptella (Chopralla) colorata, larva (holotype). 573–679, tergalii I–VII; 680, claw; 681, male larva of last instar; 682, abdominal terga IV–V; 683, abdominal tergum X. Abbreviation: MP, medioposterior sigilla.

FIGURES 684–686. Centroptella (Chopralla) colorata: paratypes of C. fusina (photos by Xiaoli Tong). 684, genitalia; 685– 686, exuviae of larval abdomen.