Review of the Caribbean species of Dohrniphora Dahl (Diptera: Phoridae)

Based on previous records and newly collected material, we review the species of Dohrniphora of the Caribbean islands, not including Trinidad. Five species are present: D. cornuta (Bigot), D. dispar (Enderlein), D. divaricata (Aldrich) and two new species, D. seriata and D. sexspinosa. We redescribe the three previously known species, and illustrate all with scanning electron micrographs of the posterior face of the hind femur and drawings of the male genitalia. Both of the new species are unusual in having six scutellar setae instead of the usual four. The species D. cavifemur Borgmeier is synonymized with D. divaricata, and the allotype male identified as D. cornuta. A key to the males of Caribbean species of Dohrniphora is provided.


Introduction
The genus Dohrniphora Dahl is a large group (currently 167 species) of phorids found worldwide. Although the life history of most species is unknown, some have larvae that are scavengers, fungivores, kleptoparasites, facultative predators, and parasitoids (Disney 1994). One species, D. cornuta (Bigot), has been accidentally introduced around the world, and is occasionally of economic importance, entering houses, infesting food, and causing human myiasis . We are currently revising the New World species of the genus (Kung and Brown 2005), with over 80 described species. As part of this revision, we herein treat the species found in the Caribbean islands, excluding Trinidad (the fauna of which is essentially South American and has been partly covered by Disney 1995), based on older material and newly collected specimens from recent survey projects.

Methods and materials
This study, like most modern revisions of Dohrniphora species, is based on male specimens. Female Dohrniphora are much less distinctive than the males, and lack the most important diagnostic characters (the setae and sculpturing of the inner face of the hind femur) used for species recognition. Most specimens in this study were collected into alcohol, critical point-dried, and either card point-mounted or glued to insect pins. In addition to the usual specimen labels, all specimens were labelled with a unique number (often with a barcode), and entered into a database. The barcode numbers are cited for holotypes to facilitate their later recognition.
Maps of species distributions based on the records cited herein, as well as other, non-Caribbean records, are available at www.discoverlife.org. Users can type ''Dohrniphora'' on the search page, then click on the name of the species of interest, and then ''Global Map.'' SEM illustrations of all species will be deposited in MorphBank (www.morphbank.org).
The following collection abbreviations are used: CMNH, Carnegie Museum of Natural History; LACM, Natural History Museum of Los Angeles County; MCZC, Museum of Comparative Zoology, Harvard University; USNM, United States National Museum, Smithsonian Institution.

Diagnosis
Dohrniphora cornuta has distinctive fine dorsobasal setae on the posterior face of the hind femur, in addition to a group of four to five ventrobasal peg-like setae (Figures 1, 2). In his 1969 Dominica paper, Borgmeier describes the mid coxa as dark brown. We have examined specimens from the same localities, and the mid coxa is clearly yellow, the same colour as the rest of the legs.
We also examined the holotype female of Dohrniphora cavifemur Borgmeier, described from Dominica, and hereby synonomize it with D. divaricata (see below). The hind femur of the allotype male of D. cavifemur, however, resembles that of D. cornuta, except for the ''dorsal excavation''. A specimen of D. divaricata we examined had a similar distortion of the hind femora when placed in phenol, and thus the defining character of D. cavifemur is shown to be an artifact of preparation.

Diagnosis
Dohrniphora dispar is recognized by the orange, enlarged flagellomere 1 (Figures 21, 22) and the unusually broad and darkened fore tarsomere 5 (Figure 19). The distinct dark, circular carina on the posterior face of the hind femur, posterior to a group of approximately 60 ventrobasal peg-like setae also help distinguish it from other species (Figures 3, 4).   Figure 19). Postcoxal lobes not developed. Posterior face of hind femur (Figures 3, 4) with dark, ventral circular carina surrounding concavity, apical to group of approximately 60 basal, apically-rounded, curve-tipped, peg-like setae. Hind tibia without isolated setae. Abdominal tergites with yellow anterior and posterior margins, yellow medially, dark brown laterally. Venter of abdomen white to yellow. Mean cercus length 0.27 mm; range 0.23-0.30 mm (Figures 25, 26).

Diagnosis
Among Caribbean species, Dohrniphora divaricata is differentiated by its four scutellar setae, and the presence of a shallow depression apical to approximately 22-34 scattered peg-like setae on the posterior face of the hind femur. The number and pattern of peg-like setae vary, although there are usually two rows along the ventral margin, in addition to a larger group of setae dorsal to the row (sometimes in a curved or triangular pattern) ( Figures 5-12).
We examined the holotype female of Dohrniphora cavifemur Borgmeier and found it to be a probable female of D. divaricata. Although taxonomy of Dohrniphora is based on males, the number of tergal plates and colour of the mid coxa allowed us to match it with other Caribbean specimens of D. divaricata. The distortion of the hind femur, given by Borgmeier as the main character of this species, is an artifact of preparation (see Diagnosis section of D. cornuta).

Description
Male. Mean body length 2.09 mm; range 1.66-2.50 (Figures 5-12) with large triangular group of basal peg-like setae; number of setae varies, but usually with two rows along ventral margin of femur and several more dorsal peg-like setae (see further discussion in Variation, below); also with shallow round depression posterior to setae. Hind tibia without isolated setae. Abdominal tergites dark brown, yellow medially. Venter of abdomen white. Mean cercus length 0.26 mm; range 0.20-0.30 mm (Figures 27, 28).

Variation
The variation in the setae of the posterior face of the hind femur is extensive. Specimens from the type locality in Saint Vincent have the largest number of setae ( Figures 5, 6), and are similar to mainland specimens we have seen (for example from Costa Rica). Sampling is insufficient to determine if this variation has a strong geographical component, and whether certain patterns are restricted to individual islands. Some of the variants are shown here (Figures 5-12).

Material examined Distribution
British Virgin Islands, Puerto Rico, US Virgin Islands.

Etymology
From the Latin word series, meaning row, referring to the ventrobasal row of setae on the posterior face of the hind femur.