Polyplectropus bredini

Chamorro, Maria Lourdes & Holzenthal, Ralph W., 2010, 2582, Zootaxa 2582, pp. 1-252 : 76-77

Polyplectropus bredini species group, newly recognized

The P. bredini group contains 19 species, including several species previously in the P. charlesi group ( P. misolja , P. kingsolveri , P. mignonae , P. mathisi , P. hymenochilus , P. perpendicularis , and P. nicaraguensis ) and P. thilus group ( P. clauseni and P. maesi ). In addition, P. panamensis is now included in the P. bredini group and the P. panamensis group of Bueno has been dissolved. Seven new species now belong in the P. bredini group. The monophyly of the P. bredini group was weakly supported and most likely represents a number of species groups.

All species in the group lack embedded spines in the endothecal membrane, with the possible exception of P. hymenochilus and P. colombianus . Polyplectropus hymenochilus appears to have several short, lightly sclerotized spines in the endothecal membrane, but this was difficult to confirm because the endothecal membrane failed to evert for the specimens examined. Polyplectropus colombianus appears to have a single, lightly sclerotized spine. Additionally, P. misolja has 3 short spines embedded in a dorsal membrane of the phallic sclerite, but not in the endothecal membrane; these spines also failed to evert. Nevertheless, the absence of spines is not a feature unique to this group.

Homoplasious characters supporting the monophyly of the P. bredini group include intermediate appendage basally broad and narrowing apically, dorsolateral process of preanal appendage absent, mesoventral process angled (45 degrees) to straight (180 degrees) and rectangular in shape (as seen in lateral view), peg-like setae present on the dorsal branch of the inferior appendage, peg-like setae on ventral branch present and located apically, dorsolateral arms of dorsal phallic sclerite tapering apically alongside dorsal phallic sclerite (forming a leveled apex), and fork 5 of hind wing sessile. However, this combination of characters does not adequately characterize this heterogeneous group of species. Therefore, 2 subsets of species within the P. bredini group are recognized.

The P. trilobatus subset includes P. brasilensis , P. clauseni , P. colombianus , P. corniculatus , P. flintorum , P. panamensis , P. petrae , P. trilobatus , and P. woldai characterized by the combined possession of the following traits:

1. Oblong shape of intermediate appendage bearing few setae basally and apically;

2. Presence of more than 4 peg-like setae on mesoventral process of preanal appendage (except P.

colombianus, P. trilobatus , or P.woldai );

3. Presence of a dorsolateral process of the preanal appendage (except P. panamensis and P. petrae ).

Within this subset of species, P. brasilensis , P. clauseni , P. trilobatus , and P. woldai have a submedially and highly incised (sinuate) posterior margin of sternum IX ( Fig. 36) whereas P. petrae and P. corniculatus have a deeply concave posterior margin with a slight median flange ( Fig. 42). P. colombianus has a unique posterior margin of sternum IX, being medially membranous ( Fig. 41) and P. flintorum and P. panamensis have a slightly sinuate margin with a median flange ( Fig. 43) (the primitive condition also present in the rest of the species in the group).

The second subset of species ( P. bredini subset) in the P.bredini group includes P. adamsae , P. bredini , P. hymenochilus , P. kingsolveri , P. maesi , P. mignonae , P. misolja , P. nicaraguensis , and P. perpendicularis and is characterized by the combined possession of the following traits:

1. Narrowly digitate, elongate (as long as or longer than inferior appendage) intermediate appendage with setae throughout ( Fig. 37);

2. Apex of phallic sclerite oblong (when observed in lateral view), in caudal view apex of phallus concave forming a trough ( Fig. 49);

3. Mesoventral processes almost quadrate (visible in lateral view) ( P. nicaraguensis is an exception since the mesoventral process is bulbous; additionally this process is less quadrate in P. hymenochilus and P. kingsolveri ) ( Fig. 37);

4. Ventral branch of inferior appendage subquadrate with posterior margin slightly angled (visible in ventral view) and apically bearing a transverse row of peg-like setae ( Fig. 37);

5. Ventral branch of inferior appendage in lateral view with rounded apex narrowing dorsad ( Fig. 37);

6. Prominent lower lip of segment X ( Fig. 37);

7. Phallic spines absent.

The shape of the intermediate appendage, the mesoventral process of the preanal appendages, the ventral branch of the inferior appendage and the dorsal phallic sclerite of the phallus change little among species in the P. bredini subset. Polyplectropus hymenochilus , P. kingsolveri , P. maesi , and P. misolja have an elongate dorsolateral process of the preanal appendage, absent in all other members of the subset.