Thursday, May 23, 2024

[Entomology • 2019] Prymnotomis cecidicola • A New Cecidogenous Species of Many-plumed Moth (Lepidoptera: Alucitidae) associated with Cordiera (Rubiaceae) in the Brazilian Cerrado


Prymnotomis cecidicola  Moreira & Becker,
 
in Moreira, Pereira, Becker, Specht et Gonçalves, 2019.

Abstract
Larvae of many-plumed moths (Alucitidae), especially in the world-wide genus Alucita Linnaeus, 1758 are known as borers or gall-inducers on flowers, fruits and shoots of a few dicotyledonous families, including Bignoniaceae, Caprifoliaceae and Rubiaceae. However, there is no study available on the biology of the monotypic, Neotropical genus Prymnotomis Meyrick, 1931 except for its original description that was based on a single male, the holotype of Prymnotomis crypsicroca Meyrick, 1931 from Espirito Santo, Brazil. We describe here a second species for this genus, Prymnotomis cecidicola sp. nov. whose larvae induce galls on Cordiera elliptica (Cham.) Kuntze (Rubiaceae), a dioecious plant with dimorphic inflorescences found in the Brazilian Cerrado, Planaltina City, Federal District. Adults, larvae, pupae and galls are illustrated under light and scanning electron microscopy. Galls are green, spherical, unilocular and develop individually on C. elliptica flower buds. During development they look like fruits in shape and colour but are larger, do not have style scars when on female plants, and are induced also in male inflorescences. Pupation occurs outside the gall within a silk cocoon, presumably in the litter. A preliminary analysis of DNA barcode sequences including putative members of other alucitid lineages and Neotropical BINs (Barcode Index Number) supports Prymnotomis cecidicola sp. nov. as an independent phylogenetic unit, with 12 to 18% divergence. Its nearest-neighbour was the BIN cluster 5 (BOLD:AAA0842) that includes specimens from Costa Rica.

Key words: Alucitid moths, Brazilian Savanna, insect galls, Prymnotomis, taxonomy


Pinned-dried adult of Prymnotomis cecidicola sp. nov. (2) dorsal view, and corresponding morphology (3–7) in detail: (3) right forewing apical angle (indicated by rectangle in Fig. 2); (4) left hind wing discal cell area (marked by asterisk in Fig. 2); (5) right hind wing outer margin (delimited by brackets in Fig. 2); (6,7) head in dorsal and lateral views, respectively; (8) left hind leg, anterior view. Scale bars: 2.5, 1, 1, 1, 0.5, 0.5, 2 mm, respectively.

  

Prymnotomis cecidicola Moreira & Becker, sp. nov.
 
Diagnosis: Prymnotomis cecidicola shares with the closely related Hexeretmis Meyrick the porrect maxillary palpi, forewing cleft only to 1/5 from termen, and pattern of wing venation. However, it differs from this genus in general appearance in coloration pattern and by presenting deeper hindwing clefts (ca 1/3 of wing length), as pointed out by Meyrick (1931). P. cecidicola can be separated from the congeneric P. crypsicroca Meyrick by the smaller size of the latter, whose forewing length of the type specimen measures ca 6 mm, and by the less contrasting coloration of P. crypsicroca, especially in relation to the hindwing. The basal process of the valva of the male genitalia is upturned, finger-like, covered with sparse filiform setae in P. crypsicroca, while in P. cecidicola it is turned down, looking like a claw, bearing short, stout spines on the base.

Etymology: The species name is derived from the Greek kekis – idos = gall + the Latin co – col = with; to be treated as feminine.

Natural history of Prymnotomis cecidicola sp. nov. on Cordiera elliptica:
(49) host plant at the type locality; (50) young fruit and gall on female plant (gall is marked by asterisk; closed arrow indicates style scar of the fruit); (51) dissected gall showing last instar larva (seta indicates sphere made of faeces and exuviae attached to the gall wall); (52) external aspect of empty gall, showing larval exit orifice (pointed by open arrow); (53) dissected empty gall, showing sphere of packaged faeces and exuviae with fecal pellets left aside (pointed by closed arrow) by the larva before leaving for pupation; (54) fresh cocoon made by last larval instar in association with sand grains and dead-broken leaves under laboratory conditions; (55) mature fruit; (56) senescent empty gall.
Scale bars: 3, 3.5, 4, 1, 3.5, 3.5 mm, respectively.

  


 Gilson R.P. Moreira, Cristiano M. Pereira, Vitor O. Becker, Alexandre Specht and Gislene L. Gonçalves. 2019. A New Cecidogenous Species of Many-plumed Moth (Alucitidae) Associated with Cordiera A. Rich. ex DC. (Rubiaceae) in the Brazilian Cerrado. Zoologia. 36: 1-15. DOI: 10.3897/zoologia.36.e34604