Diatraea nayaritella Robles & Solis, 2024

Robles-Pérez, Rafael & Solis, M. Alma, 2024, A new species of Diatraea Guilding, 1828, feeding on sugarcane from Nayarit, Mexico, and a lectotype designation for Diatraea magnifactella Dyar, 1911 (Lepidoptera, Crambidae, Crambinae), Zootaxa 5536 (4), pp. 569-580 : 574-577

Diatraea nayaritella Robles & Solis , sp. nov.

urn:lsid:zoobank.org:act:6088DC4E-AF9C-431A-AC9F-A2464BBF5496

( Figs. 5–6 , 10–13 )

Type material. Holotype: ♂, MEXICO, Nayarit, Santa María del Oro municipio, San Leonel ejido, 07/02/2022, Lat. 21.353958, Long. 104.693823, #550, Collector Rafael Robles-Pérez, USNMENT01894344. The holotype is deposited in the NMNH . Allotype: ♀, MEXICO, Nayarit, Tepic municipio, Francisco I. Madero ejido, 12/02/2022, Lat. 21.614016, Long. 104.823457, #312, Collector Rafael Robles-Pérez, USNMENT01894339. Deposited at the NMNH . Paratypes: 1 ♂, 1 ♀, MEXICO, Nayarit, Tepic: Ejido: Santiago de Pochotitan , 18/02/2022, Lat. 21.591408 Long. 104.707154, #437, Alt. 792 msnm; Ejido: Francisco I. Madero, 25/01/2022 Lat. 21.564841 Long. 104.821599, #6, Alt. 773 msnm . 2 ♂, 2 ♀, MEXICO, Nayarit, Santa María del Oro, Ejido Zapotanito : 04/03/2022, Lat. 21.321911 Long. 104.627989, #474, Alt. 1,161 msnm; 04/03/2022, Lat. 21.321911 Long. 104.627989, #484, Alt. 1,161 msnm; 04/03/2022, Lat. 21.321911 Long. 104.627989, #489, Alt. 1,161 msnm; Ejido San Leonel: 04/03/2022, Lat. 21.361985, Long. 104.704702, #515, Alt. 1,076 msnm . 1 ♂, Municipio Xalisco, Ejido Xalisco , 05/03/2022, Lat. 21.434987, Long. 104.899262, #635, Alt. 984 msnm . 1 ♀, Municipio Santiago Ixcuintla, Ejido Gavilán Grande , 09/02/2022, Lat. 21.786320, Long. 105.311135, #218, Alt, 7 msnm. Deposited at the NMNH .

Additional material examined. More than 300 genitalia of specimens from Nayarit, not part of the type series, were dissected and their genitalia compared. Two are figured, 1 ♂, MEXICO, Nayarit: Municipio Santiago Ixcuintla, Ejido Puerta de Mangos, 11/02/2022, Lat. 21.734986 Long. 105.323038, #326, Alt. 6msnm, Collector Rafael Robles-Pérez, USNMENT01899047 ( Figs. 10–12 ); 1 ♀, MEXICO, Nayarit: Municipio Tepic, Ejido Francisco I. Madero, 25/01/2022, Lat. 21.564841, Long. 104.821599, #4, Alt. 773 msnm, Collector Rafael Robles-Pérez, USNMENT01899043 ( Fig. 13 ) .

Diagnosis. Average forewing length (range in parentheses): male=15.0 mm (14–16 mm), n=5; female=18.0 mm (17–20 mm), n=5. Externally ( Figs. 5–6 ), this species resembles almost all other Diatraea species, except that the male has medial dark brown spots on the abdomen. It differs from other Diatraea species in genitalia characters as mentioned in the Morphological comparison below. Male genitalia ( Figs. 10–12 ): tegumen lateral lobe (tll) broad, and slightly arched, not square, not pointed, or not rounded like a finger; valva costa basal lobe (cbl) present, with subequal basal and apical widths, entire lobe wider than long and distally slightly straight (in a few specimens it was straight); juxta with two lateral projections and juxta arms pointed. Female genitalia ( Fig. 13 ): corpus bursae not straight, 3 times longer than ductus bursae, with a protrusion or bulge about 1/3 distance from ductus bursae, followed by an arch in the form of a slight constriction, ductus bursae half the width of the posterior section of the corpus bursae.

Morphological comparison. We compare D. nayaritella , sp. nov., with D. considerata due to the close morphological similarity of the genitalia to the new species. The forewing length of D. considerata is only slightly shorter in males with an average forewing length of 14.4 mm (14–15 mm) (n=5), but slightly longer in the female, 19.25 mm (19–20 mm) (n=4). In D. considerata , males ( Fig. 3 ) have beige and darker brown forms, and the females are light beige with a shiny, white hindwing. In D. nayaritella , the male ( Fig. 5 ) and female ( Fig. 6 ) forewings are light beige, but the hindwing in the male has only a dusting of brown scales, and the female hindwing is shiny white, similar to the hindwing of D. considerata . The male abdomen of D. nayaritella ( Fig. 5 ) has dark brown medial spots that are lacking in D. considerata . In the male genitalia of D. considerata ( Fig. 9 ) the tegumen lateral lobe (tll) is rounded like a finger, and slightly pointing upward, whereas in D. nayaritella ( Fig. 10 ) the lobe is broad and slightly arched, the costa basal lobe (cbl) of the valva in D. considerata is not straight as in D. nayaritella , but curved or bulging outward, and in D. considerata the tip of the juxta arms is flat, not pointed as in D. nayaritella . In the female genitalia of D. considerata (see Fig. 26a, USNM slide #114641, in Solis & Metz, 2016), the corpus bursae is mostly straight (although slightly curved in the type slide) without protrusions or arches as in D. nayaritella ( Fig. 13 ), and in D. considerata the ductus bursae is almost as wide as the posterior section of the corpus bursae, whereas in D. nayaritella the ductus bursae is half as wide as the posterior section of the corpus bursae ( Fig. 13 ).

In the Solis and Metz (2016) key to the male genitalia of Diatraea (starting at p. 11), D. nayaritella would key from #31, “Valva basal costal lobe strongly crenulate, carinate and/or denticulate,” then #32, “Lateral lobe of tegumen bluntly pointed or rounded”, to #34, D. considerata , “Valva basal costal lobe base with basal and apical widths subequal, entire lobe wider and long.” Note: a separate couplet in the male genitalia key would be needed to separate D. nayaritella from D. considerata (see above). In the key to female genitalia (starting at p. 14), D. nayaritella would key from #7, “Corpus bursae length at least 2X greater than width, extending well beyond anterior margin of sternite VIII”, then #8, D. considerata or magnifactella , “ductus bursae with longitudinal grooves, uniformly darkened throughout length from ostium to corpus bursae; corpus bursae with pair of acuminate strips of darker cuticle descending from ductus bursae.” Note: a separate couplet in the female genitalia key would be needed to separate D. nayaritella from D. considerata / magnifactella (see above).

Distribution. The new species is known to occur only in the state of Nayarit, Mexico ( Fig. 1 ), but in the future, it could be discovered in adjacent sugarcane zones in the states of Jalisco, Colima, and/or Michoacán.

Biology. Diatraea nayaritella , sp. nov., is known to feed only on sugarcane, but other species of Diatraea have been reported to feed on other species of Poaceae , such as corn, sorghum, wheat, rice ( Box 1951a, b, Box 1953a, b). A total of 1,441 specimens were collected, and 654 (345 males and 309 females) survived to adult on an artificial diet.

Molecular data. As part of a Master degree program, Robles-Pérez (2021) sequenced material of the new species, D. nayaritella , sp. nov. (GenBank access key MW193580.1, identified as D. considerata ), and compared the COI sequences with the sequences in GenBank. This comparison showed that the specimens collected in Nayarit had a 98.91% match with specimens identified as D. aff. considerata / magnifactella (JQ888376.1, JQ888375.1), but we were unable to locate the publication in which these sequences along with information on methodology, locality, or reason for the scientific name were provided. In Sinaloa, a separate study by Vejar-Cota et al. (2016) reported the sequence for specimens confirmed to be D. considerata , and in their analysis the new species, D. nayaritella was also labeled as D. aff. considerata / magnifactella .

Etymology. This species is named for the state of Nayarit, Mexico, founded in 1917, and whose name in Náhuatl means “son of god that is in the sky and sun.”

Figures

FIGURES 13. D. nayaritella Robles & Solis, sp. nov., female genitalia, paratype, #4, Nayarit, Mexico, USNMENT01899043 (female mounted dorsoventrally with the abdominal segments pulled aside). Scale bar: 5mm.

FIGURES 3–6. Adults. 3, Diatraea considerata Heinrich, holotype, male, El Dorado, Mexico, USNMENT01433904. 4, Diatraea magnifactella Dyar, lectotype, male, Orizaba, Mexico, USNMENT0143236. 5, Diatraea nayaritella Robles & Solis, sp. nov., holotype, male, Santa María del Oro, Nayarit, Mexico, USNMENT01894344. 6, Diatraea nayaritella Robles & Solis, sp. nov., allotype, female, USNMENT01894339, Tepic, Nayarit, Mexico.

FIGURES 7–12. Male genitalia. 7, D. magnifactella, lectotype, USNM slide #97395, vinculum/valvae/phallus. 8, D. magnifactella, lectotype, USNM slide #97395, tegumen/uncus/gnathos, USNM slide #97395. 9, D. considerata, holotype, genitalia including phallus, USNM slide #97489. 10, D. nayaritella Robles & Solis, sp. nov., vinculum, valvae, paratype, #326, USNMENT01899047.11,D.nayaritellaRobles&Solis,sp.nov.,tegumen/uncus/gnathos,paratype,#326,USNMENT01899047. [tll=tegumen lateral lobe, cbl=costa basal lobe]; 12, D. nayaritella Robles & Solis, sp. nov., phallus, holotype, #326, Nayarit, Mexico, USNMENT01899047. Scale bar: 1mm.

FIGURES 1–2. 1, Map of Mexico with western states labeled (S=Sinaloa, Nayarit, Inset map and the focus of this study, J=Jalisco, C=Colima, M=Michoacán. 2, Sugarcane dead heart sample being collected by RRP in Nayarit.