Sufetula diminutalis (Walker)

Hayden, J. E., 2013, Sufetula Walker in Florida (Lepidoptera: Crambidae), Insecta Mundi 2013 (296), pp. 1-15 : 10-13

Sufetula diminutalis (Walker)

( Fig. 8–12 , 20–22 , 26–28 )

Isopteryx diminutalis Walker, 1866: 1315 .

Hydrocampa dematrialis Druce, 1896: 276 , pl. 63 fig. 25.

S [ufetula] sp.: Kimball, 1965: 200.

Diagnosis. Ocelli are absent. The labial palpi do not have ventral scale tufts or, at most, have a few apically projected scales ( Fig. 12A, B ). Females have two frenular bristles. The forewing length (base to apex) is 4.5–7.5 mm, mean 5.4 ± 0.3 mm, and width (costa to tornus) is 1.5–2.5 mm, mean 1.9 ± 0.1 mm (n = 20; Fig. 8–11 ). In the forewing, Rs 2 and Rs 3 are distally separate, and Rs 4 is very short-stalked with their stem ( Fig. 20 ). The forewing PM line is extended slightly distad from the costa to the median fold, then runs nearly parallel to the wing axis between veins M 1 and M 2. The forewing costa has two distinct white lunules, and the terminal margin between Rs 4 and M 3 is black. The hind wing PM line meets the costa about 3/5 distance from the wing base. In the male tympanal organs ( Fig. 21 ), the posterior depressions are rounded without lateral angulation. The female tympanal organs ( Fig. 22 ) are obliquely elongate, as in S. carbonalis . The abdomen is not otherwise modified ( Fig. 28 ). In the male genitalia, the valva is 3.3 to 4 times longer than wide, and the costa is slightly expanded halfway along in a very shallow angle ( Fig. 26 ). The manica ( Fig. 26 : ma) is microspiculose but lacks large spines, plates, or other distinct sclerotizations. The vesica bears a double row of many small cornuti. The uncus is elongate and bears lateral shoulders. In the female ( Fig. 27 ), the ductus bursae is long, narrow, of nearly even width, and sclerotized evenly from just anterior of the ductus seminalis to the corpus bursae, bearing small spines in the far anterior end.

Similar species. Concerning congeners outside of Florida, Dyar (1914) differentiated the Central American S. hypochiralis Dyar and S. hypocharopa Dyar from S. diminutalis ; inter alia, they have forewings with a broad, white streak on the posterior half of the cell to Cu veins, and a narrower hind wing PM area. Sufetula hypocharopa has labial palpi without a ventral tuft, the manica has many dense spinules, the ductus bursae is very long, coiled and unsclerotized, and the signum is a round, granulose field, like the Asian S. sunidesalis Walker. Sufetula dulcinalis (Snellen) of Colombia also has a narrow hind wing PM area, about 3/4 from the wing base (holotype examined, not dissected).

Sufetula diminutalis is most likely to be confused with Anageshna primordialis (Dyar) , a common spilomeline. They are the same size and general maculation ( Fig. 16 ). In Anageshna , the forewing AM and PM lines are nearly straight across the wing, and the pale costal spots are not surrounded or centrally filled with black. In the genitalia (not shown), males have broad valvae and a capitate uncus similar to Microphysetica , and females have a short ovipositor and elongate ductus bursae without an obvious colliculum. The larger, more brightly colored Apogeshna stenialis (Guenée) is structurally similar to A. primordialis . Other similar Spilomelinae in Florida include species of Steniodes Snellen , Eurrhyparodes Snellen and Loxostegopsis Dyar.

Two musotimines in Florida are similar in size and structure to S. diminutalis . Undulambia polystichalis Capps has labial palpi with the apical meron long, upturned and acicular. Males are strikingly patterned with orange and white with a radial fovea in the forewing. Females ( Fig. 14 ) are dark brown, and the genitalia have short papillae anales, no colliculum, and the ductus seminalis arising from a small expansion between the corpus and ductus bursae. Neomusotima conspurcatalis (Warren) , released in Florida to control the Old World climbing fern, Lygodium microphyllum (Cav.) R. Br. ( Boughton and Pemberton 2009) , has palpi similar to those of S. diminutalis . In addition to other musotimine characters discussed above, the maculation is mostly brown, lunules are absent on the forewing costa, the PM line is more evenly curved, and the hind wing has terminal black spots. Males have a small androconium around the foreleg epiphysis and robust valvae with a fibula and inflated sacculus, and females have a sclerotized lamella postvaginalis ( Solis et al. 2004).

Material examined. Lectotype: (rectangular white label with black underline) “ Honduras ”, (round green-bordered label) “Type”, (round white label, obverse) “ Honduras Limas”, (same, reverse) “61 21”, (typed) “ ISOPTERYX ? DIMINUTALIS.”, (white label) “Photographed B.M. negative” ( BMNH).

Additional material examined: USA, Florida: 1M: “ FLORIDA: LEVY CO. Goethe State Forest Intersection of North Prong Road & Middle Rd OCT 10 2010 MV/ BL Terhune S. Dickel ” ( TSD) ; 5M, 6F: same data except at bait, Dec. 2, 9 and 15, 2012 ( TSD) ; 1M: Goethe St. For. 30-XI- 2009 ( TSD) ; 1F: Goethe St. For. 7-XII-2009 ( TSD) ; 1M: “FL: Levy Co. Goethe St. For. Gasline & Beehive Rds. 29°09’38"N, 82°35’55"W. 23-VII-2011. Pine flatwoods, beer-fruit bait. J. Hayden, T. Paris, M. McCowan” ( FSCA) ; 1F: same data with “ J.E. Hayden slide 1404 F” ; 1F: same data except “ 30-VII-2011 ” ; 1F: same data except “ 6-VIII-2011 ” (JEH wing slide 1439) ; 1F: same data except “ 12- X-2012 ” ; 1M: same data except “ 12-I-2013 ” ( MGCL body slide 918, wing slide 919) ( FSCA) ; 2M, 2F: “USA, FL: St. Lucie Co. A & L Agricultural Labs, with Rhapis sp. 14-VIII-2007 R. Murray via L. Buss. E2007-6805” ( FSCA) ; 1M, 3F: “FL: Dade Co. Homestead 07-6183 20 Aug 2007 H. Mayer ex Rapis excelsa ”, [one] “ Anageshna primordialis (Dyar) det. J.B. Heppner ’07" ( MGCL slides 96, 97) ( FSCA) ; 1F: “FL: Putnam Co. Palatka At MV/UV light”, “ 10-VII-1992 Leg. H.D. Baggett ” ( MGCL slide 273) ( FSCA) ; 1: “ Homestead, Fla. V.8 1959 D.O. Wolfenbarger ”, “ C.P. Kimball det. 1959”, [pencil] “5351” ( FSCA) ; 1M: “ Oneco, Manatee Co., Fla. V.5 1953 Paula Dillman”, “ Sufetula diminutalis Wlk. Det. E.G. Munroe ”, “5351” ( FSCA) ; 1M: “ FLORIDA: Collier Co. Collier Seminole State Park 26 Jan 1986 Linwood C. Dow ”, “ Sufetula diminutalis ” (FSCA) ; 1F: “ FLORIDA: Alachua Co., Austin Carey Forest , 10 mi. NE Gainesville 19-26-VIII-75”, “ collected by malaise trap ”, “ T. E. Rogers coll.” ( FSCA) ; 1F and larvae (alcohol vial): FLORIDA: Dade Co. Miami R. Quinones coll. ex Ravenea rivularis , 25-IV-2006, FSCA # E2006-2032 ( MGCL slide 566) ( FSCA) ; 1F (alcohol vial): FL: Miami- Dade Co. Homestead, 25.491612°N 80.363512°W in Red palm weevil trap, 25-VI-2012, A. Derksen, FSCA #E2012-4847 ( MGCL slide 578) ( FSCA) ; 1M, 1F (alcohol vial): FL: Miami-Dade Co. Homestead, 25.51987°N 80.379904°W in Palm weevil trap, 18-I-2013, J.M. Torres, FSCA #E2013-0457 ( FSCA) ; 3F: FL: Glades Co. Palmdale, Fisheating Creek Campground, US Rte. 27, on Jackson trap with cue [tephritid] lure. 29-I-2013 M. Terrell. E2013-0688 ( FSCA) ; 1M: “ Homestead, Fla. x.9 1959 D.O. Wolfenbarger ”, (Munroe’s hand) “5351”, “Database # CNC LEP 00097601” ( CNC) ; 1M: same data except “ xi.4 1959 ”, “CNC LEP 00097602” ( CNC) ; 2M: same data except “ iv.10 1959 ”, one with “CNC LEP 00097603”, “ J.E. Hayden slide No. 1851 M”, another with “CNC LEP 00074731”, (blue label) “ Barcode of Life DNA voucher specimen Simple ID: CNCLEP00074731 BOLD Proc. ID: ZYPAN530-10” ( CNC) ; 1M: “USA: FL: Port Everglades CBP via Dominican Republic ex fruit of Cocos nicifera [sic] 06.VII.2011: R. Singam Int # APMFL111875562001”, [green label] “[male] gen slide By MA Metz USNM 114,581”, “ Sufetula diminutalis Walker Det. M.A. Solis ” ( NMNH) ; 1M: “Apr. 1-7”, “Everglade Florida ”, [red-rimmed label] “ Dematrialis Druce x T in Berl. M. Ju [illeg.]”, [large label] “ Is this actually a synonym of S. diminutalis ? CPK.” ( NMNH); 1F: “ FLORIDA Vero Beach July 1941 J.R. Malloch ” ( NMNH) ; 1M, 7F: “Stemper, Fla.”, “Barnes Collection”, May 24-31, June 1-7, July 1-7, July 8-15, one with large label “ The Stemper lot are all S. dematrialis ” Druce. CPK.” ( NMNH) . COSTA RICA: 1F: Sixola R. March. Collection Wm. Schaus ; 1M, 1F: Heredia, La Selva Field Sta. near Puerto Viejo , 21–28 March 1988, W.E. Steiner et al. ( NMNH) . CUBA: 1M, 1F: Baracoa , Oct. Coll. Wm. Schaus ( NMNH) . DOMINICAN REPUBLIC: 1M: Santo Domingo, San Francisco Mts. Sept. 1905, Aug. Busck ( NMNH) . JAMAICA: 1M: Trelawny Parish, 1150ft. Mr. & Mrs. E.L. Bell. “9” ( NMNH) . PANAMA: 1M: Alajuelo , April [19]11, August Busck ; 1F: Cabima, May. [19]11, August Busck ( NMNH) . VENEZUELA: 1F: Aragua, Rancho Grande , 1100m, 11-15 July 1981 cloud forest, J. Heppner ( NMNH) .

Distribution. The type locality is Lima, Honduras. It is distributed in the Caribbean, southern Central America and northern South America; in addition to records above, it is recorded from Colombia, Peru and Bermuda ( Genty and Mariau 1975; Ferguson et al. 1991). Florida counties include Alachua, Collier, Levy, Manatee, Miami-Dade and Putnam. The species is probably distributed throughout peninsular Florida as far north as Gainesville (Alachua County) and Palatka (Putnam County).

Phenology. Specimens have been collected in Florida all months except February, March and September. They have been collected at bait from dusk to well past midnight. Genty and Mariau (1975) stated that adults are active in the early morning and at dusk.

Remarks. The diagnosis suffices to differentiate S. diminutalis from S. carbonalis . Most species of Sufetula were described from one or few specimens, without explicitly comparative diagnoses and without descriptions of genitalia. The only previously published genitalic illustrations are of S. sacchari ( Seín 1930) . Females may be the same size as males or up to 33% larger, as shown by a series taken at one site in Goethe State Forest in December 2012.

Genty and Mariau (1975) studied the larval behavior of S. diminutalis as pests of palm roots in South America. They described methods of rearing and control, and they gave general (albeit non-comparative) descriptions of the life stages. Occasional infestations of ornamental palms in Florida are consistent with these accounts, where larvae bore into the growing tips of roots. Sufetula diminutalis has been recorded very recently in Germany, based on specimens caught in an enclosed exhibit area stocked with exotic plants (Richard Mally, pers. comm. 2012).

Sufetula diminutalis is attracted to sugar bait of molasses, bananas and beer, reliably although in small numbers, equally by sex. This was discovered through the efforts of T. S. Dickel in Goethe State Forest in pine flatwoods habitat carpeted with saw palmetto, Serenoa repens [Bartram] Small. I have consistently attracted the species at bait, but not at light, at one of the same localities. Specimens have also been attracted to molasses-baited palm weevil traps in Homestead, Florida, and this behavior may be more general among related species ( Muus 2008). Flight-intercept or malaise traps yielded the German specimens, one from Austin Carey Forest (Gainesville), and the holotype of S. carbonalis .

Lack of diapause may explain the northern limit of the distribution of the species. Genty and Mariau (1975) indicated that the life cycle is about one month from egg to eclosion, so adults should be encountered year-round. The association with palms is another explanation for the distribution.

Discussion. The classification of Sufetula is problematic. The genus is undoubtedly a crambid, as evinced by the praecinctorium, tympanal structure and chaetotaxy ( Seín 1930; Hayden unpubl.). The genus traditionally has been placed in Pyraustinae ( Hampson 1899) , specifically in Spilomelini or Spilomelinae where specified (Munroe in Hodges 1983). Although none of the authors have explicitly stated reasons for this classification, Sufetula shares with Spilomelinae the absence of four structures: chaetosemata, the male frenulum hook, an obvious gnathos and a rhomboidal signum ( Munroe 1976; Minet [1982]). However, other evidence challenges this placement. The tubular forewing CuP vein is not present in Spilomelinae: it is present only in Schoenobiinae , some Acentropinae and some outgroup Pyralidae ( Forbes 1926; Lange 1956). The small, ventrally directed posterior depressions of the tympanal organs are unlike the invaginated sacculi and puteoli of most spilomelines, and likewise the laterally projected fornix tympani is unlike the ventrally projected condition in Spilomelinae (Minet [1982]). The non-bilobed praecinctorium is present only in a minority of Spilomelinae. A strongly spiculose manica is shared with Scopariinae , Schoenobiinae and Midilinae ( Hayden 2012: Fig. 5F ). Although a male frenulum hook is absent in observed specimens of Sufetula (contra Forbes 1926), it is in fact present in a few other genera that otherwise share many characters, such as Leechia South and Neobanepa Hampson. The larvae of S. diminutalis and S. saccharalis possess two subventral setae on the eighth abdominal segment ( Seín 1930; pers. obs.), elsewhere known only in Pyralidae sensu stricto and Cybalomiinae ( Hasenfuss 1960; Nel et al. 2004). Finally, subterranean or internal feeding in monocotyledonous plants is uncommon in Spilomelinae but very common in certain other subfamilies ( Crambinae , Schoenobiinae , Midilinae , some Scopariinae ). However, the absence of characters shared uniquely with any one other subfamily prevents a satisfactory placement.

Sufetula is closely related to the Old World genus Diplopseustis Meyrick. One species , D. perieresalis (Walker) , has been examined recently in connection with its spread in the nursery trade in Western Europe ( Speidel et al. 2007). The authors referred it to Spilomelinae for similar reasons as for Sufetula . The species is associated with sedges ( Patrick 1994) and palms ( Gaedike 2010), and it tolerates temperate and even subantarctic-oceanic climate ( Patrick 1994). If it were to be imported accidentally into North America on nursery stock, it would presumably spread over a broader range than the two species treated above. Diplopseustis is also attracted to sugar bait ( Muus 2008). It can be distinguished from native Florida Sufetula species by its smoothly curved forewing PM line, short valvae, absence of manica lamellae, and the elongate, unsclerotized ductus bursae.

Figures

Figures 8–16. Florida crambids. 8–11) Sufetula diminutalis from Florida. 8) Male, Levy Co.: Goethe State Forest, 30 Nov. 2009 (TSD). 9) Same site, 30 July 2011 (FSCA). 10) Miami-Dade Co.: Homestead, 20 Aug. 2007 (FSCA). 11) Female, Putnam Co.: Palatka, 10 July 1992 (FSCA). 12) Females, lateral aspect of head: A, with normal labial palpi (Levy Co. Goethe State Forest, 12 Oct. 2012, FSCA); B, variation of labial palpi with a few ventrally projected scales (Goethe SF, 9 Dec. 2012, TSD). 13–16) Similar Floridian crambids. 13) Microphysetica hermeasalis, Picayune State Forest, 2007, J. Vargo (FSCA). 14) Undulambia polystichalis, female, Pinellas Co.: Dunedin, 19 March 1987 (FSCA). 15) Elophila obliteralis, male, Alachua Co.: Gainesville, 1975 (FSCA). 16) Anageshna primordialis, Manatee Co. (FSCA). Scales = 5 mm.

Figures 17–22. Sufetula spp. 17–19) Sufetula carbonalis. 17) Venation (male, MGCL slide 540). 18) Male tympanal organs (MGCL slide 540). pd, posterior depression. 19) Female tympanal organs (JEH slide 1590). pd, posterior depression. 20–22) Sufetula diminutalis. 20) Venation (female, JEH slide 1439). 21) Male tympanal organs (MGCL slide 96). 22) Female tympanal organs (MGCL slide 578). Scales = 0.5 mm.

Figures 23–29. Genitalia. 23–25) Sufetula carbonalis. 23) Male genitalia (MGCL slide 98). jx, juxta; lb, labriform margin; lm, lamellae of manica. 24) Female genitalia (JEH slide 1590). co, colliculum; ob, ostium bursae. 25) Male abdominal cuticle (MGCL slide 540). 26–28) Sufetula diminutalis. 26) Male genitalia (MGCL slide 96). jx, juxta; ma, manica attached to phallus. 27) Female genitalia (MGCL slide 578). 28) Male abdominal cuticle (MGCL slide 96). 29) Microphysetica hermeasalis, Puerto Rico: Maricao State Forest, male genitalia (MGCL slide 670). Scales = 0.5 mm.

Figures 1–7. Sufetula spp. 1–5) Sufetula carbonalis, habitus and head. 1) Holotype, abdomen removed. 2) Highlands Co., Archbold Research Station, 2 May 1975 (FSCA). 3) Levy Co., Goethe State Forest, 30 July 2011 (FSCA). 4) Sarasota Co., Siesta Key, 8 April 1953 (FSCA). 5) Lateral aspect of head with large ventral scale tuft (same data as Fig. 2). 6) Sufetula grumalis, left wings, Cuba: Santiago, 1925 (NMNH). 7) Sufetula sacchari, left wings, Puerto Rico: Rincon, 22 Feb. 1971 (NMNH). Scales = 5 mm.