DOI: 10.15468/uapfqm
title: Bledius beattyi Blackwelder (Coleoptera: Staphylinidae: Oxytelinae), New to the United States, and Co-Occurrences of some Bledius Leach and Dyschiriodes Jeannel (Coleoptera: Carabidae: Scaritinae) Species in South Florida

description: This dataset contains the digitized treatments in Plazi based on the original journal article Thayer, Margaret K., Purrington, Foster F. (2004): Bledius beattyi Blackwelder (Coleoptera: Staphylinidae: Oxytelinae), New to the United States, and Co-Occurrences of some Bledius Leach and Dyschiriodes Jeannel (Coleoptera: Carabidae: Scaritinae) Species in South Florida. The Coleopterists Bulletin 58 (3): 439-442, DOI: 10.1649/720, URL: http://dx.doi.org/10.1649/720AbstractBledius beattyi Blackwelder, 1943 (Coleoptera: Staphylinidae: Oxytelinae) and Dyschiriodes sublaevis (Putzeys, 1846) (Coleoptera: Carabidae: Scaritinae) are both recorded from Big Pine Key, Florida, providing the first United States record for the former and the first Bledius Leach - Dyschiriodes Jeannel co-occurrence (likely prey-predator) record for both species. In combination with previously published data, these records provide the first information on possible predatorprey associations for B. ceratus Blackwelder, 1943 as well.The genus Bledius Leach contains roughly 450 described species worldwide, divided into 34 species groups by Herman (1972, 1976, 1983, 1986). As far as known, all are active algivorous burrowers in damp substrates where females rear larvae, found variously near freshwater or saline habitats. To date, 88 species in 10 species groups have been recorded from North America north of México (Newton et al. 2000; Herman 2001). One of these, the B. aequatorialis group of Herman (1972), consists of four species: B. ceratus Blackwelder, 1943 from the Florida Keys (plus Bahamas, Cuba, Hispaniola, Jamaica), one from Texas, and two solely Neotropical (Herman 1983, 2001). One of the latter, B. beattyi Blackwelder, 1943, has now been collected on Big Pine Key (Monroe County), Florida, adding a species to the United States (and North American) fauna (see Material Examined).Males of the B. aequatorialis group are readily recognized by having two pairs of supra-antennal horns (reduced to small swellings in one species) and among New World species by having a pronotal horn. Herman (1986) provided additional characters also applicable to females. Bledius beattyi is distinguished from the other members of the B. aequatorialis group by the uninterrupted lateral marginal bead of the pronotum and having two small subapical teeth (rather than one) on each mandible (Herman 1972, 1983). The species was described from St. Croix (U. S. Virgin Islands) and Vieques I. (Puerto Rico) and subsequently recorded from Cuba, the Yucatán Peninsula of México, Puerto Rico, and Colombia (Herman 1972, 1983; see Fig. 1). It is thus not completely unexpected in the Florida Keys, but this record represents a range extension of around 180 km and into the USA proper. Most of the records are coastal, although the type was collected inland, along a stream (Blackwelder 1943). The new Big Pine Key collection was made at a saline coastal mud flat mostly enclosed by black mangroves (Avicennia germinans L.), a post-pioneer species, and inhabited by fiddler crabs (Uca sp.). Herman (1972) recorded the closely related B. ceratus and the more distantly related B. mandibularis Erichson, 1840 from apparently similar habitat (‘‘mud flats near coastal mangrove swamps,’’ 1972: 169) on Big Pine Key in December. The lack of prior collecting of B. beattyi there could reflect a difference in seasonality between it and B. ceratus or possibly a change in faunal composition during the intervening decades. In February 2004, this area was entirely flooded (F.F.P. pers. obs.), suggesting that there may be considerable year-to-year variation in the exact locations where such interstitial species are able to live.Fig. 1. Distributions in Gulf of Mexico and Caribbean Sea. Bledius beattyi: •, published records; m, new records. Dyschiriodes sublaevis: s, published records; e, new record.Because Bledius species are commonly preyed upon by species of the fossorial scaritine carabid genera Dyschirius and Dyschiriodes (Herman 1986, as Dyschirius Bonelli; see Ball and Bousquet 2000 regarding the nomenclatural change), it is of interest that Dyschiriodes sublaevis (Putzeys, 1846) was recently collected at the same locality on Big Pine Key (see Material Examined). This species (as Dyschirius sublaevis) has been recorded from coastal Texas, U.S.A. and Yucatán, México (Whitehead 1970); Dunedin (Pinellas County), Florida (Nichols 1988; Peck and Thomas 1998); and mapped (Nichols 1988, without locality data) as occurring elsewhere in Florida (Collier County and Florida Keys [Monroe County]: Key West?) and in Cuba (near Havana), as shown in Figure 1. The level of specificity of associations between Dyschiriodes species and species of Bledius on which they prey is uncertain, as discussed in detail by Herman (1986; as Dyschirius), and the volume of relevant data available is still relatively limited. Herman’s (1986) records of species associations between the genera included none involving either B. beattyi or D. sublaevis. This note thus provides the first two such records (of at least co-occurrence) for those two species: USA: Florida: Big Pine Key (data below), and México: Yucatán: Progreso, on beach (D. sublaevis: Whitehead 1970; B. beattyi: Herman 1972) and also two other Bledius-Dyschiriodes associations: USA: Florida: Big Pine Key, mud flats (D. sublaevis: data below; B. ceratus and B. mandibularis: Herman 1972). This is the first co-occurrence record of B. ceratus with any Dyschiriodes. It appears from Nichols’ (1988) map that D. sublaevis may also occur with B. beattyi in the vicinity of Havana, Cuba.Nichols (1988) characterized D. sublaevis as a halobiont and suggested that such species are more likely to achieve circum-Caribbean distributions than are riparian species. On the contrary, B. beattyi, although not strictly a halobiont (Blackwelder 1943; Herman 1972), has achieved an even wider circum-Caribbean distribution than the partly syntopic D. sublaevis.