Chonocephalus Wandolleck, 1898

Disney, R. H. L., 2008, Review of Neotropical Chonocephalus Wandolleck (Diptera: Phoridae), Zootaxa 1772 (1), pp. 1-54 : 3-4

Genus Chonocephalus Wandolleck, 1898

Type species. Chonocephalus dorsalis Wandolleck, 1898: 428 .

The genus is readily identified in the most recent key to world genera ( Disney, 1994), with the modification that the genus Epichonocephalus Schmitz has been synonymised with Chonocephalus ( Disney, 2002) . The same paper provides a detailed diagnosis of the genus in both sexes. The wings of the males are distinctive ( Figs 18 and 64 ) as is the general appearance of the females ( Figs 47 and 66 ).

The full details of the references for synonyms, etc., covered by Disney (2002) are not repeated in this paper.

Males. The recognition of species depends primarily on the details of the hypopygium, which is at first sight very complex. However, if one ignores the, often elaborate, penis complex (X), the details of the epandrium (E) and hypandrium (H) that are referred to in the key below are indicated in Fig. 1 . This represents a generalised, stylized, hypopygium. While the anal tube (A) is seldom utilised in the recognition of species it is a useful point of reference. Any one of the labelled structures may be modified and may sometimes be very elaborate in form. In the inferred groundplan state the rear margin of the hypandrium bears four processes. These are the gonopods (G) and a pair of median lobes (L). In the plesiomorphic state the gonopods articulate with the dorsal face of the hypandrium, but more frequently they arise from it. One (usually the left) or both may be reduced or absent. The median lobes (L) may form a single bilobed structure or be reduced to a single lobe (which may be greatly elongated) or be lost altogether. Ventrally each side of the epandrium (E) typically bears an anterior process (AP) and a posterior process (PP). In some species the anterior processes (AP) may appear to be appendages (attaching to the inner face of the epandrium) rather than simple projections of the epandrium. A presumed true left surstylus or clasper (C) is frequently present (e.g. Figs 17 and 24 ), variably fused to the epandrium, and is sometimes elaborate. Occasionally it is fused to the bridge (B), which is sometimes present and probably represents sternite 10. The most anterior (lower) bristle of the left side of the epandrium is sometimes modified into a spine (S), which may be further modified.

Females. The critical details of the terminal segments of the abdomen are indicated in Figs 109–110 , which depicts a basic (close to the groundplan) state of a female Chonocephalus ( Disney, 1986) . In most species the T9 is lost apart from its anterolateral apodemes, which are fused to those of T10 so that the latter appear to be two-branched.

Review of species. The descriptions of the new species are brief as the significant features of the males are largely restricted to the details of the hypopygia. Likewise in the females there are relatively few features that distinguish the species apart from the details of the abdominal terminalia. The formal diagnoses, therefore, are the features used to distinguish the species in the keys above.

The brief notes on the natural histories of the species, when known, are taken from Disney (2002) except where indicated otherwise. Typical larvae and pupae are shown in Figs 70–74 .

Figures

FIGURE 1. Chonocephalus male hypopygium, diagrammatic ventral view of a generalised species. A = anal tube (with median hypoproct and paired cerci); E = epandrium; H = hypandrium; X = penis complex (simplified). AP, PP = anterior and posterior processes (probably = subepandrial sclerites) of epandrium; L = lobe(s) of hypandrium; G = gonopods; B = bridge (probably = sternite 10); C = left surstylus (clasper); S = spine (modified bristle) of epandrium.

FIGURES 15–18. Chonocephalus aripoensis: (15) male, right lobe of hypandrium; (16) male, left face of hypopygium; (17) female, abdominal sternite 8 and spermatheca; (18) male, right wing. Scale bars = 0.1 mm.

FIGURES 64–65. Chonocephalus heymonsi: (64) male, right wing; (65) female, posterior face of hind leg from femur onwards. Scale bars = 0.1 mm.

FIGURES 47–48. Chonocephalus dominicanus female: (47) whole fly from above; (48) sternite 8, furca and spermatheca. Scale bars = 0.1 mm.

FIGURES 66–68. Chonocephalus heymonsi female: (66) whole fly from above; (67) tergite 8; (68) sternite 8, furca and spermatheca. Scale bars = 0.1 mm.

FIGURES 24– 26. Chonocephalus browni male, details of hypopygium: (24) left side of epandrium from below; (25) right side of epandrium and right gonopod from below; (26) hypandrium and gonopods from left side. Scale bar = 0.1 mm.

FIGURES 109– 110. Details of the terminal segments of the abdomen of the basic (presumed groundplan) state of a female Chonocephalus (the Oriental C. blackithorum Disney, 1986) from above (109) and from below (110). C = cercus, H = hypoproct, Sp = spermatheca, S8 = sternite 8, S9 = the internalised sternite 9 (= furca), T7–T10 = tergites 7 to 10. Scale bar = 0.1 mm.

FIGURES 70–71. Chonocephalus heymonsi larvae: (70) first instar; (71) third instar. (After Borgmeier, 1935).

FIGURES 72–74. Chonocephalus heymonsi pupae: (72) eclosion plate of puparium; (73) anterior cap of puparium; (74) left face of pupa. (After Borgmeier, 1935).