Debilos Townes, 1966, 1970

Scherrer, Marcus V. & Aguiar, Alexandre P., 2012, 3469, Zootaxa 3469, pp. 1-76 : 5-9

Debilos Townes, 1966

Debilos Townes , in Townes & Townes 1966:326. Description, keyed. Type species: Cryptus soror Trentepohl , by monotypy and original designation.

Debilos: Townes, 1970:257 . Redescription, taxon added, figure, keyed.

Debilos: Yu & Horstmann, 1997:239 . Listed.

Debilos: Ruíz et al., 2002:41 . Distribution records. Debilos: Yu et al., 2005 . Listed.

Debilos: Kasparyan & Ruíz, 2005:189 . Keyed.

Diagnosis. Mandible small, slender, MLW 1.50–2.27, apex very narrow, MWW 0.33–0.60, with ventral tooth with half size of dorsal tooth ( Fig. 1); supra-antennal area with longitudinal median carina or line, sometimes indistinct at middle, without median horn or tubercle ( Fig. 3); epomia short, delicate to indistinct, but sometimes moderately stout ( Fig. 5); hind rim of metanotum with pair of small tooth-like projections ( Fig. 2); propodeum posterior transverse carina represented only by pair of short, conical to very long, thorn-like apophyses ( Figs 9–13, 49–53, 91–120); first metasomal segment very slender, T1LW 2.53–3.77, T1WW 2.27–3.16, without basolateral tooth ( Fig. 6); ovipositor moderately long and slender, laterally somewhat compressed, lanceolate ( Fig. 4), dorsal valve with nodus and notch absent or faint, tip without serrations, ventral valve tip with serration absent or inconspicuous and restricted to very tip ( Figs 19, 21–24), or rarely with inconspicuous serrations along entire tip ( Fig. 20).

Redescription. Fore wing about 3.44–10.00 mm. Body slender, mostly minutely colliculate-punctulate, covered with moderately dense, short pilosity.

Head. Small, rather in males. Female flagellum subapically swollen (e. g., Fig. 88); supraclypeal centrally area inconspicuously to not swollen; clypeus small, distinctly convex, often moderately prominent, base almost indistinct, apical margin without median teeth; mandible small, very slender, about 1.64–3.00 × as long as base width, apex very narrow, about 0.33–0.67 × as wide as base width, ventral tooth about half of dorsal tooth length (e. g., Fig. 1); supra-antennal area with longitudinal median carina or line, sometimes indistinct at middle, without median horn or tubercle ( Fig. 3); occipital carina complete, uniformly curved, reaching hypostomal carina above mandible base; temple and gena not swollen.

Mesosoma . Pronotum dorsal margin not swollen, lateral portion usually faintly to distinct substrigate to rugose, epomia short, delicate to indistinct, but sometimes moderately stout ( Fig. 5); mesoscutum subcircular, slightly elongate; notaulus inconspicuously to moderately impressed, reaching maximally mesoscutum middle, surface sculpturing over notaulus slightly, inconspicuously corrugated to uniformly sculptured with mesoscutum; scutoscutelar groove distinctly corrugated (e. g., Fig. 41); mesopleuron dorsal half centrally faintly to indistinctly strigulate or rugulose, epicnemial carina well marked, incomplete, restricted to mesopleuron ventral 0.5–0.8, sternaulus quite conspicuous, reaching middle coxa, often centrally faintest; postpectal carina medially somewhat straight to distinctly bent; metapleuron apical fovea small, subcircular, often shallow or moderately deep (e. g., Figs 51–53), juxtacoxal carina absent; pleural carina present, complete, somewhat inconspicuous to stout; hind rim of metanotum with small tooth-like projections ( Fig. 2), transverse furrow between metanotum and propodeum smooth, narrow, moderatelly deep (e. g., Fig. 91). Propodeum: apical margin medially straight to slightly concave; propodeal spiracle circular to elongate, about 1.00–2.88 × as wide as long; anterior transverse carina present, often distinct, rarely faint or inconspicuous, sometimes medially slightly to moderately arched forwards; posterior transverse carina represented only by pair of sublateral, short, conical to very long, thorn-like apophyses (e. g., Figs 92, 96, 100); propodeum anterior area often long, with maximum height about 0.44–1.33 × as long as propodeum posterior area behind apophyses (e. g., Figs 49, 50); propodeum posterior area sculpturing variable, from uniformly colliculate with anterior area, or entirely rugulose, to moderately or markedly strigulate-rugulose, often with ridges medially arched backwards (e. g., Figs 7–14). Legs: female fore tibia not swollen; pre-apical tarsomeres bilobed, with lobes of about equal to distinctly unequal size, hind t4 posterior lobe about 0.15–0.95 × as long as anterior lobe. Wings (e. g., Figs 25–40): hyaline, or with uniform yellowish tint. Fore wing sometimes with one inconspicuous to distinct apical dark spot, usually covering apical half of cell 3M and 1+2R1, or two faint to distinct dark spots, the apical one and a basal spot usually covering cell 1Cu apical parts; with minute and moderately sparse pilosity covering entire wing length, except cell 1Cu basal 0.4 centrally and cell A basal 0.25 almost glabrous; vein (Rs+M)b straight to thinly sinuous, with bulla basal, ramellus mostly absent, rarely distinct, limit with 1m-cu distinct, except when (Rs+M)b sinuous and ramellus absent; vein Rs&1M posteriorly to uniformly slightly curved; crossvein 1cu-a straight, slightly uniformily curved or with posterior half slightly curved, arising opposite or apicad Rs&1M, forming 90 degrees or slightly obtuse angle with vein M+Cu; vein 2Cu about 0.39–1.11 × as long as crossvein 2cu-a, in males about half the length of crossvein 2cu-a, veins not aligned; vein 2Rsb slightly to distinctly sinuous; bulla at crossvein 2m-cu somewhat central, about 0.3–0.1 × as long as vein length; cell 1+2Rs (areolet) small to moderately large, about 0.27–1.17 × as high as pterostigma maximum width, pentagonal, approximately as wide as high, open (r-m not differentiated); 2Mb normal, entirely tubular or absent, spectral; vein 2Rsb slightly to distinctly sinuous. Hind wing basally almost glabrous, with minute and moderately sparse pilosity towards apex; vein M+Cu most distinctly curved at apical 0.2–0.3; vein 1Cu distinctly longer than crossvein cu-a, about 1.17–2.70 × as long as crossvein cu-a; vein 2-1A often long, almost complete, or moderately short, reaching at least about half distance to wing margin or longer, sometimes very short or absent, reaching only 0.2 × less the distance to wing margin.

Metasoma. T1 long and very slender, maximum length about 2.53–3.77 × maximum width, with sculturing varible from subsmooth to punctulate, completely ecarinate, without lateral triangular tooth or flange at base ( Fig. 6), with spiracle not prominent to conspicuously prominent, at T1 basal 0.6–0.7; gaster minutely coriaceus to finely imbricate, somewhat polished towards apex; T2 often moderately short and apically robust, rarely elongate, with apex about 1.80–2.82 × as wide as base; thyridium variable, from small and subcircular to largest and irregular. Ovipositor sheath about 0.43–0.74 × as long as hind tibia; ovipositor glabrous, moderately long and slender, slightly downcurved or approximately straight, laterally faintly compressed, lanceolate ( Fig. 4); dorsal valve with nodus and notch absent or faint, tip distinct to gradually sharpening, without serrations; ventral valve tip with serration absent or inconspicuous and restricted to very tip ( Figs 19, 21–24), or rarely with inconspicuous serrations along entire tip ( Fig. 20).

Comments. The key provided by Townes (1970) for the world genera of Goryphina, though very useful in general investigation, should not run perfectly well to some Debilos specimens. This is because the second couplet of the key might generate some doubt when it states that Debilos must have the “portion of propodeum in front of basal carina very long” and “female with long, thorn-like propodeal apophyses.” In fact, some species show particularly low CHP ratios, such as Debilos dnopheror (0.44), D. dialeucor (0.48), and D. palaior (0.48), suggesting that an enlarged portion of the propodeum in front of basal carina seems not to be constant in the genus, even while very frequent. Similarly, some species have propodeal apophyses not distinctly long, which is particularly common in the largest species ( D. dialeucor , D. dnopheror , D. palaior , and D. soror ). Thus, the mentioned couplet can incorrectly lead to a group of Old World Goryphina genera plus the Neotropical Hylophasma Townes. Nevertheless , a misidentification can be avoided with a analysis of the propodeal apophyses, which form sublateral crests in Hylophasma and is quite different from the conical apophyses in Debilos species.

From the redescription of Debilos given by Townes in the same work, apart from the two characters discussed above, some characters also were modified or expanded here based on the examined specimens. Townes (1970) described Debilos having the epomia faint and short, females legs with the pre-apical tarsomeres with lobes of about equal, or slightly unequal sizes, hind wing vein 2-1A (brachiella) reaching almost to wing margin, and ovipositor tapered evenly from a faint nodus to apex, with ventral valve without teeth except near apex. However, after the discover of some exceptions or differences in the species proposed by the present work, wich probably were not examinated by Townes, the description of these characters were now redefined. Therefore, species of Debilos are now known by having the epomia short, delicate to indistinct, but sometimes moderately stout, females legs with pre-apical tarsomeres bilobed, with lobes of about equal to distinctly unequal size, hind wing vein 2-1A often long, almost complete, or moderately short, reaching at least about half distance to wing margin or longer, sometimes very short or absent, and ovipositor with nodus and notch absent or faint, with ventral valve tip with serration absent or inconspicuous and restricted to very tip, or rarely with inconspicuous serrations along entire tip. Even so, the body size and general shape, combined with T1 without lateral triangular tooth or flange at base can make the species of the genus resemble the species of Lymeon Foerster , despite being member of Lymeonina , a different subtribe. Conversely, species of Debilos can be also somewhat similar to species currently corresponding to the definition of Diapetimorpha Viereck , mainly by the similar color patterns and body size. However, species of Debilos can be easily separated from Lymeon by having mandible apex narrower, with ventral tooth about half size of dorsal tooth, fore wing crossvein 1cu-a arising opposite or apicad vein Rs&1M and ovipositor ventral valve often without serrations, or with inconspicuous serrations, whereas species of Lymeon have mandible more stout, with ventral tooth about 0.6–0.8 × as long as dorsal tooth, fore wing crossvein 1cu-a arising distinctly basad vein Rs&1M and ovipositor ventral valve with serrations present. The genus can also be distinguished from Diapetimorpha by having the mandible more small and slender, with apex narrower than in species of Diapetimorpha , but in addition to this the first metasomal segment without basal tooth easily differentiate Debilos from such species.

In fact, the lack of the basal pair of teeth in the first metasomal segment is an important state to separate Debilos from most New World Goryphina. Besides Diapetimorpha , also Baltazaria Townes and Listrognathus Tschek have this feature present. Only Loxopus Townes , among these genera, have the first metasomal segment without basal tooth as in Debilos , however, this genus can be readily separated from Loxopus by having the propodeum posterior transverse carina represented only by pair of short to very long sublateral conical apophyses whereas Loxopus has the posterior transverse carina present, usually evanescent or indistinct at center and with faint to well marked sublateral crests.

Species delimitation. Debilos spp. can have some characteristic interspecific morphological patterns. The most extreme variations among these species, however, seem to be rather restricted to color patterns and body size, with the species having a range of average variation of the fore wing length from 3.44 to 10.00 mm. General sculpturing, pilosity and most biometric ratios otherwise proved to be very similar between the examined species of Debilos , wich generally presented few morphological variations.

Of the 29 recognized species, 27 seem to belong into at least 5 morphological groups of species, adopted here to facilitate discussions on interspecific variability, therefore also aiding species-level determinations. These five groups are characterized below.

Debilos soror species group: includes D. soror , D. dnopheror , D. dialeucor , and D. palaior ; recognized by having the mesosoma black, fore wing without dark spots ( Figs 25, 26), propodeum posterior area strigulaterugulose, with ridges often well marked ( Figs 7, 11), with short, conical apophyses ( Figs 92–95), dorsal valve of ovipositor with nodus faint but always present, and ventral valve with inconspicuous serrations, restricted to very tip ( Fig. 19). Their short, conical, almost tubercle-like propodeal apophyses seems to be unique among the species of Debilos . This diagnostic feature, along with their large body size, having a range of average fore wing length of about 7.40–10.00 mm, and the color pattern almost entirely black, except by D. soror with legs deep orangish, makes the species of soror group easily recognizable against other species of the genus.

Debilos orthum species group: includes D. orthum and D. gnampthum ; recognized by having the mesosoma black, fore wing without dark spots, propodeum posterior area strigulate-rugulose, with ridges often well marked ( Fig. 8), with thorn-shaped apophyses ( Figs 96, 97), and ovipositor without nodus and with ventral valve tip without serrations ( Fig. 21). Forms a group of species with body size slightly smaller than species of D. soror group, and having a range of average fore wing length of about 6.56–7.20 mm. Because of their body size and color pattern mostly black, these species can be wrongly associated to the soror group, but should be differentiated from this group by observing the coxae with large whitish marks ( Figs 96, 97), the propodeal apophyses of regular height, thorn-shaped and the ovipositor dorsal valve without nodus.

Debilos typurum species group: includes D. typurum , D. owinum , D. pekujum , D. okum , D. okarum , D. umentum , D. aserum , D. anokum , D. masipum , D. sanimum , D. tasamunum , and D. makirum ; recognized by having the mesosoma brownish, fore wing with one or two dark spots (e. g., Fig. 33), propodeum posterior area faintly to moderately strigulate-rugulose, with ridges medially slightly arched backwards ( Figs 9, 49, 50), and with long, thorn-shaped apophyses ( Figs 102–113), and ovipositor without nodus and with the ventral valve tip without serrations, or sometimes with inconspicuous serrations restricted to very tip ( Fig. 21). The species under these attributes present a medium body size, having a range of average fore wing length of about 4.10–6.32 mm, and forms a large group that comprises very similar and moderately different species and can possibly be segregated, as soon as new taxa are added in the future. Some species of the D. prionilix and D. trochanteratum groups may resemble species of the D. typurum group mostly by similar body size and color, but they are readily differentiated from these groups by having the propodeum posterior area faintly to moderately strigulate-rugulose and fore wing vein 2Mb normal, as tubular as vein 2Ma ( Figs 34, 37, 38). Debilos frater may also fit in this group by the attributes listed above, but should be not included in any group presented here, as discussed in the “Comments” of its species description.

Debilos prionilix species group: includes D. prionilix and D. crusilix ; recognized by having the mesosoma brownish, fore wing with two dark spots ( Fig. 32) and areolet small and with vein 2Mb spectral, inconspicuous or absent ( Fig. 35), propodeum posterior area rugulose, with ridges not forming distinct pattern, and with long, thornshaped apophyses ( Figs 99, 100), dorsal valve of ovipositor with nodus faintly developed but always present, and ventral valve with inconspicuous and widely spaced serrations along its tip ( Fig. 20). Because they have similar color pattern and the medium sized body length, having a range of average fore wing length of about 3.44–5.25 mm, the species of this group can be at first mistaken for those of D. typurum species group. However, they can be easily separated from that group by having ovipositor tip with nodus present at dorsal valve and with inconspicuous and widely spaced serrations at ventral one, as far as known unique between species of the genus, and fore wing vein 2Mb distinctly nebulous.

Debilos trochanteratum species group: includes D. trochanteratum , D. melachrosatum , D. petiolatum , D. nivatum , D. curtuvenatum , D. labeculatum , and D. xanthochrosatum ; recognized by having the fore wing with areolet moderately large, with the vein 2Mb distinctly spectral or absent ( Fig. 36), propodeum posterior area uniformly colliculate with anterior area ( Fig. 12), with long, thorn-shaped apophyses ( Figs 114–120), propodeal spiracle mostly distinct subrounded ( Fig. 58) and ovipositor without nodus and with the ventral valve tip without serrations, or sometimes with inconspicuous serrations restricted to very tip ( Fig. 24). These species form a slightly colorful and small sized group, having a range of average fore wing length of about 3.44–5.25 mm. The species of D. prionilix group, even with general body shape not very similar, do have also the fore wing with vein 2Mb nebulous or absent and the propodeum posterior area uniformly colliculate with anterior area, and may be mistaken recognized as being species of D. trochanteratum group. However, species of the present group can be differentiated by having the areolet moderately large, the dorsal valve of the ovipositor without nodus and the ventral valve without serrations, or with serrations inconspicuous and restricted to very tip. Debilos indistinctum may also resemble species of this group, but should be not included in any group presented here, as discussed in the “Comments” of the species description.

It might seem remarkable that the females of most species from the Brazilian Atlantic Forest ( D. masipum , D. sanimum , D. curtuvenatum , D. tasamunum , and D. indistinctum ) have the T3 on apical half and T4–8 mostly or entirely dark yellowish ( Figs 101, 111–114), which is so characteristic that this could suggest this is a group of species by itself. However, the greater number of other morphological features discussed above provide best support to the proposed division as discussed above.

Due to the highly similar morphological structure, body size and color pattern for all the species within a same species group, along with the fact that they also often occur in sympatry, species-level distinction is likely to be difficult, and might be ambiguous sometimes. Most problems can however be solved by careful observation of some of these most variable features, such as the color pattern of pedicel and flagellomere 1 ( Figs 89, 90), clypeus ( Figs 73–85), mesoscutum ( Figs 41, 42), coxae ( Figs 92–124), hind leg as a whole, primarily tarsus ( Figs 59–70), and metasoma (e. g., Figs 92, 99, 101, 115, 122). In addition, the fore wing can present two dark spots, at the apical and basal portions ( Figs 30–32), or only the apical spot distinct, with basal one inconspicuous or absent (e. g., Fig. 33), or also both dark spots might lack ( Figs 25–27). Other important characters are the shape of the postpectal carina on its median portion ( Figs 45, 46), presence or absence of fore wing ramellus (e. g., Figs 27, 28), length of hind wing vein 2-1A (e. g., Figs 29, 30), length of propodeum anterior area ( Figs 49, 50), and the shape of the metasomal thyridium ( Figs 17, 18).

Biology. Unknown.

Distribution. The genus seems to be entirely Neotropical. The valid species are distributed from Panama to the southeastern Brazil, comprising about 29°37’ of latitude ( Fig. 154). In addition, Ruiz et al. (2002) reported the occurrence of an unnamed species for Mexico, at the state of Oaxaca, reinforcing Townes (1966), who first pointed the occurrence of Debilos in this country.