“Progebiophilus kensleyi, new species
?Pseudione species.—Barnard, 1950:520 [Gordon’s Bay, east side of False Bay {=Valsbaai}, Cape Province, Atlantic coast, South Africa, 34◦10’S, 18◦52’E; 1 damaged / infesting Upogebia Africana (Ortmann)].
Material examined.—Infesting Upogebia africana (Ortmann). Kowie River Estuary, Port Alfred, Indian Ocean coast, Cape Province, South Africa, 33◦33’S, 26◦53’E, January to June, 1967, B. J. Hill, coll.: 1 ♀ holotype, USNM 173461; 1 ♂ allotype, USNM 173462; 58 ♀, 34 ♂, paratypes, USNM 173463.
Description.—Holotype female Length 11.71 mm, maximal width 7.64 mm, head length 2.57 mm, head width 3.43 mm, pleon length 3.29 mm; distortion of body axis 118, sinistral. Body outline elliptical and smoothly curved; all body regions and segments distinct. No eyespots or other pigmentation.
Head suboval, smoothly curved and continuous with pereonal margin anteriorly, sharply angled posteriorly, short but complete frontal lamina across anterior. Both
pairs of antennae greatly reduced, each with basal article larger than all others together, of 4 and 3 articles respectively, only sparsely setose. Barbula with 2 broad falcate processes on each side, their margins deeply digitate, smaller digitate flap medially, crenulate margin in center. Maxilliped oval, longer than broad, its anterior article about twice as long as posterior one, bearing anteriorly placed extended tapering nonarticulating palp; anterior border of maxilliped and margin of palp sparsely setose; posterior article produced anteromedially into tiny, very slender and sharply pointed plectron.
Pereon widest across pereomere 3, that one nearly parallel front and back, anterior
pereomeres concave anteriorly, posterior ones concave posteriorly. Obscure middorsal ridge along pereomeres 2–7. Shallow oval pits on both sides of dorsal surfaces of most pereomeres. Coxal plates completely covering both sides of all pereomeres. Oostegites completely enclosing brood pouch and widely overlapping. First oostegite semioval anteriorly, produced into short blunt posterolateral projection, minutely setose along anterior margin, its articles of about same length, external ridge prominently inflated and multilobed, with scalloped margin posteriorly; internal ridge with many tiny digitate processes irregularly aligned. Other oostegites extended far medially but short from front to back, all with setose margins, those of fifth pair bearing rows of long slender setae posteriorly. Pereopods all well-developed and extending slightly beyond pereonal margins, increasing in size posteriorly; meri and carpi fused in anterior pereopods, separate in posterior ones; all dactyli reduced and not overreaching edge of propodi, all carpi with finely setose anterior margins.
Pleon of 6 pleomeres, all visible both dorsally and ventrally; ventroposterior margins of most pleomeres nearly straight but deeply scalloped. Five pairs of biramous pleopods (those on left side somewhat more prominent in each pair) and one pair of uniramous uropods overlapping and completely covering sides of pleon; all rami irregularly ovate and produced into blunt to sharp posterolateral points; rami progressively smaller and their points sharper posteriorly; all margins of rami as inflated ridges scalloped internally.
Allotype male. Length 4.25 mm, maximal width 1.48 mm, head length 0.41 mm, head width 1.07 mm, pleon length 1.09 mm. All body regions and segments distinct and deeply divided laterally, outline elongated ellipse. Minute dark slit-shaped eyespots near posterior margin of head, no other pigmentation.
Head semicircular, smoothly rounded anteriorly and convex posteriorly. Antennae well-developed, of 3 and 5 articles respectively, distal 3 articles of each fringed with prominent setae, second antennae extending far beyond margin of head.
Pereon broadest across pereomere 5. No middorsal ridge or midventral tubercles. All pereomeres deeply notched anterolaterally. Pereopods clustered beneath body, all of about same size; dactyli of first three pairs longer than others, carpi of last three pairs longer than others; opposing surfaces of meri and propodi of all pereopods minutely scaly, distal ends of meri densely setose; all meri and carpi faintly to distinctly separate.
Pleon prominently extended, of 6 pleomeres, each narrower and shorter than preceding except for lateral extensions on sixth pleomere. Five pairs of large, extended,
uniramous flaplike pleopods, some partly visible dorsally. Final pleomere produced into pair of rounded slender uniramous uropods separated by slender anal cone.
Comparison of paratype material—Of the 59 females examined, 27 are dextrally distorted, 32 sinistrally, a non-significant deviation from a 1:1 ratio. All distortion angles are very slight, so direction is occasionally difficult to assess, but the females’ pleopods are larger on the long sides. Of the 20 individuals examined in detail, body lengths range from 5.92 to 11.67 mm, their widths from 3.60 to 8.00 mm. Some have 3 distinct projections on their barbulae, several have pereopodal meri bulbous distally, the first oostegite of one has the fringe of setae only on the edge of the internal ridge; one has the maxilliped palp farther forward and the oostegite’s internal ridge less digitate. An immature female has a proportionately larger head and very reduced oostegites; many have pereopods with knobs or lumps on their surfaces.
Among paratype males, of 20 examined in detail, lengths are 2.56 to 4.04 mm, widths from 0.96 to 1.40 mm. A few lack eyes completely, while some have prominent eyes. A few have heads partly fused with their first pereomeres. One has only 5 pleomeres, one lacks fifth pleopods, and one has a single uropod medially placed. Such variations seem typical for males in several bopyrid species.
Etymology.—Latin second declension genitive kensleyi selected to honor the late Brian F. Kensley as a token of gratitude for the help and kindness that he extended to me through the years I knew him as a friend and colleague, and also because this new species occurs in South Africa, where Brian was born and began his illustrious career in carcinology.
Remarks.—The only other published record of bopyrid infestation of Upogebia Africana is the report of Barnard (1950) cited in the synonymy above. Because all species of Progebiophilus would at that time have been considered to belong to the genus Pseudione, it is likely that Barnard had the same species. Unfortunately, as he reported, the single female he had was damaged, and it further appears that he discarded it rather than placing it in the collection of the South African Museum (Michelle G. van der Merwe, pers. comm.). The material examined herein all came from a single year’s collection by Burke J. Hill, who was performing studies on the biology of the host species, U. africana (see Hill 1971). He informs me (Hill, pers. comm.) that the parasites were common in 1967 but very rare in later years.
Progebiophilus kensleyi differs distinctly from at least seven of the ten previously described species of Progebiophilus. In both sexes, it appears most similar to the European species P. euxinicus (Popov, 1927) discussed above, especially as redescribed by Bourdon (1968). The female of P. kensleyi resembles those of P. euxinicus and the Congolese species P. chapini (Van Name, 1920) as described by Van Name (1920) with further notes by Bourdon (1981) thus: all three species have only very slight axes of distortion and relatively broad heads widening anteriorly from a single posterior angle; their maxillipeds are similarly shaped; their barbulae are ornamented nearly alike; and their pereopods have similar shapes and proportions. Some of these characters are uncertain for P. chapini. The female of P. euxinicus differs from that of P. kensleyi in having a much better developed frontal lamina, less distinctly defined maxilliped palp, its first oostegite produced into a larger posterolateral projection and its uropods greatly reduced. The female of P. chapini differs at least in that its final pleomere is more reduced and embedded in the preceding one.
Males of P. kensleyi are most similar to those of P. euxinicus and P. bruscai, a species from western Mexico discussed above. Males of these three species of Progebiophilus are the only ones whose bodies are at least twice as long as broad, and whose uropods are extended. In both P. euxinicus and P. bruscai, the males’ uropods articulate with the final pleomere, rather than being fused as in P. kensleyi. In P. bruscai, the pereomeres are deeply separated medially, according to Campos and Campos (1998). Males of P. kensleyi differ markedly from those of P. chapini, to which the females of P. kensleyi are similar.
The only other species of Progebiophilus known from Africa is P. chapini, which infests Upogebia furcata (Aurivillius) in the Banana River, Bas Zaı¨re, Democratic Republic of the Congo, 05◦58’S, 12◦27’E, on the Atlantic coast. It was originally described as Pseudione chapini by Van Name (1920). The only material of P. chapini known is the types, which Bourdon (1981) partially redescribed. Unfortunately, some important details of that species still remain uncertain, and efforts to borrow the type specimens for redescription as part of this report proved unsuccessful.”
(Markham, 2005: 86-90)
