Stethobaroides nudiventris Champion, 1908

Prena, Jens, 2025, Neotropical orchid-weevils of the genus Stethobaroides Champion (Coleoptera, Curculionidae, Baridinae), Zootaxa 5723 (2), pp. 227-244 : 237-238

Stethobaroides nudiventris Champion

( Figs. 4D , 6C , 9C )

Stethobaroides nudiventris Champion, 1908: 399 . Lectotype male, here designated, labelled “Type” on disk with red margin (attached as a matter of routine by museum staff), “ ♂ ”, “Sp. figured.”, “ Mexico. Sallé Coll.”, “Toxpam”, “ B.C.A. Col. IV.5. Stethobaroides nudiventris, Champ. ” (NHMUK).

Diagnosis. At first glance, S. nudiventris ( Fig. 9C ) can be, and has been, confused with other, more southerly occurring species. Stethobaroides badicrus , with similar body proportions, is smaller and usually has reddish appendages and dense setae along the prosternal channel ( Fig. 10 ). Three other species in the same size range as S. nudiventris are slightly more ovate in the respective sex, but their distinction requires representative series and practice. Diagnostic is the ovate-lanceolate, apically pointed penis ( Fig. 4D ) and the punctate, distally gently bisinuate fifth ventrite of the female ( Fig. 6C ). The available specimens measured 2.8–3.2 mm. Lengths of up to 3.7 mm, as given by Morales Báez et al. (2016), may apply to a different species and need confirmation.

Life history. Morales Báez et al. (2016) reported that adult weevils appeared on Catasetum integerrimum Hook with the onset of the flowering season in July. Eggs were laid in young flowers and an average of three larvae developed per petal. Infested petals decayed within three days and were aborted. Pupae were not found. Córdova Ballona & Sánchez Soto (2022) confirmed the development in C. integerrimum flowers in Tabasco, reared adults but gave no further details about the development of the immature stages. Gerardo Quintos Andrade (INECOL Xalapa, personal information) found adults in the flowers of Stanhopea dodsoniana Salazar & Soto Arenas and Mormodes Lindl. in Xalapa, Veracruz. Observations on other orchids made outside México apply to different species.

Distribution. The species occurs around the Gulf of México, from the State of Taumaulipas in northeast México southward to Belize.

Material examined. MÉXICO. Veracruz-Llave: Toxpam, A. Sallé ( SDEI 1 , SNSD 4 ), digital images of lectotype and 5 paralectotypes ( NHMUK 6 ) . BELIZE. Río Hondo , F.J. Blancaneaux, digital images of paralectotypes ( NHMUK 7 ) .

Additional records. MÉXICO. Tabasco: Huimanguillo mpo., Colegio de Postgraduados, Campus Tabasco ( Sánchez Soto & Córdova Ballona 2022). Tamaulipas: Reserva de la Biósfera El Cielo, Gómez Farías ( Rosas Mejía et al. 2021). Veracruz-Llave: La Estanzuela, Emilian Zapata ( Morales Báez et al. 2016); El Espinal, Naolinco ( Morales Báez et al. 2016); El Tajín archaeological zone, Papantla ( Ortiz de Angel et al. 2019).

Notes. Stethobaroides nudiventris is the type species of the genus. Because the original series included more than one species, I designate here as lectotype the card-mounted (all others are on points) and in the original publication illustrated Toxpam specimen. Another seven specimens from Toxpam ( NHMUK 5, SNSD 2), seven from Río Hondo ( NHMUK) and one from “ Colombia ” ( NHMUK) are paralectotypes. The two SNSD specimens still have Champion’s handwritten labels, which no longer exist in the NHMUK series. I dissected one Toxpam male ( Fig. 4D ) and it agreed well with the illustrations in Morales Báez et al. (2016). Three more of Auguste Sallé’s specimens from Toxpam ( SDEI 1, SNSD 2) are labelled with the unpublished name Centrinus toxpamensis Faust. Sallé obviously distributed specimens before Frederick Godman purchased the remaining stock for the Biologia Centrali-Americana ( Godman 1915). Blancaneaux’s specimens from the Belizean-Mexican border probably belong to S. nudiventris as well, whereas the specimen from 19th Century Colombia (not identical with the territory of today’s República de Colombia) is a different species.

Toxpam (also spelled Tospam and Tuspan) refers to the pre-Hispanic site of Toxpan, northeast of Córdoba, where José Apolinario Nieto (1810–1873) owned a coffee plantation of the same name. Müller (1864) provides a vivid image of the place. As a young man, Nieto aided Charles-Alexandre Lesueur during trips to the Mexican Gulf region ( Sosa 1885, Cervera Sanchís 2013). Henry Dupont, and through him Auguste Chevrolat and others, obtained their collected beetles ( Chevrolat 1833, Dupont 1838). Sallé, who was Chevrolat’s godchild, used Nieto’s plantation as his headquarters for fieldwork in 1854–1856 ( Boucard 1875, Sclater 1897).

Figures

FIGURE 4. Stethobaroides, male genitalia, dorsal and lateral aspects. A, S. elcoranus; B, S. villus; C, S. badicrus; D, S. nudiventris (from Toxpam); E, S. permixtus (from La Selva); F, S. lauro. Scale bar 0.5 mm.

FIGURE 6. Stethobaroides, female distal ventrites. A, S. elcoranus; B, S. badicrus; C, S. nudiventris; D, S. scutellatus; E, S. permixtus; F, S. lauro.

FIGURE 9. Stethobaroides, dorsal and ventral aspects of males. A, S. piliventris from Santa Catarina Juquila, Oaxaca, México; L=4.3 mm (photos by R.S. Anderson). B, S. villus from Finca El Cora, Nayarit, México; L=4.0 mm; C, S. nudiventris from Finca Toxpam, Veracruz-Llave, México; L=3.0 mm.

FIGURE 10. Stethobaroides badicrus from La Selva Reserve, Heredia, Costa Rica. A–C, male, L=2.6 mm; D, female, L=2.8 mm.