Lunaceps incoenis ( Kellogg and Chapman, 1899 )

Gustafsson, Daniel R. & Olsson, Urban, 2012, 3377, Zootaxa 3377, pp. 1-85 : 33-38

Lunaceps incoenis ( Kellogg and Chapman, 1899)

( Figs. 13a–d for specimens from Calidris mauri and Calidris pusilla ; Figs. 14a–d for specimens from Calidris minutilla ; Table 1)

Nirmus incoenis Kellogg and Chapman, 1899: 81

Degeeriella incoenis (Kellogg and Chapman) ; Harrison, 1916: 115

Degeeriella actophila (Kellogg and Chapman) ; Peters, 1934: 36 (partim)

Degeeriella actophila (Kellogg and Chapman) ; Peters, 1936: 16 (partim)

Lunaceps incoenis (Kellogg and Chapman) ; Hopkins and Clay, 1952: 201

Lunaceps incoenis (Kellogg and Chapman) (partim); Timmermann, 1954a: 623

Lunaceps cabanisi Timmermann, 1954a: 625 . New synonymy

Lunaceps pusillus Carriker, 1956: 74 . New synonymy

Lunaceps incoenis (Kellogg and Chapman) ; Malcomson, 1960: 190

Lunaceps cabanisi Timmermann ; Malcomson, 1960: 190

Lunaceps holophaeus (Burmeister) ; Keirans, 1967: 113 (by implication)

Lunaceps sp. Keirans, 1967: 116

Lunaceps holophaeus incoenis (Kellogg and Chapman) ; Emerson, 1972: 93

Lunaceps holophaeus cabanisi Timmermann ; Emerson, 1972: 93

Lunaceps holophaeus pusillus Carriker ; Emerson, 1972: 94

Lunaceps holophaeus pusillus Carriker ; Taft and Schaper, 1979: 698

Lunaceps holophaeus (Burmeister) ; Taft and Schaper, 1979: 698 (partim)

Lunaceps incoensis [sic!] (Kellogg and Chapman); Ledger, 1980: 168

Lunaceps cabanisi Timmermann ; Ledger, 1980: 169

Lunaceps cabanisi Timmermann ; Forrester et al., 1995: 27, 28

Lunaceps pusillus Carriker ; Mayberry et al., 2000: 60

Lunaceps cabanisi Timmermann ; Price et al., 2003: 196 (partim)

Lunaceps incoenis (Kellogg and Chapman) ; Price et al., 2003: 196 (partim)

Lunaceps cabanisi Timmermann (“Clade 4”); Gustafsson and Olsson, 2012: 94 ( Figs. 1, 2).

Lunaceps pusillus Carriker (“Clade 4”); Gustafsson and Olsson, 2012: 94 ( Figs. 1, 2).

Type host: Pluvialis squatarola ( Linnaeus, 1758)

Other hosts: Calidris mauri ( Cabanis, 1857) , Calidris pusilla ( Linnaeus, 1766) , Calidris minutilla ( Vieillot, 1819)

Diagnosis of material from C. mauri and C. pusilla : Head elongated ovoid ( Fig. 13a), often with a slight concavity at the posterior margin. Marginal carina unbroken anteriorly. Ventral anterior plate long and tapered, reaching the posterior margin of the dorsal preantennal suture. Ventral preantennal suture does not divide ventral anterior plate from ventral lateral plates entirely. Dorsal preantennal suture broad and interrupted medially. AVS3 sometimes anterior to AVS2, but usually aligned with it.

Paratergal plates very narrow ( Fig. 13b), and the tergal re-entrant heads less intensely coloured than the anterior-lateral ends of the tergites. Dark border markings narrow. Tergal head of segment VII usually narrow and pointed.

Female genital lobes with 4–5 posterior marginal setae, 3 sub-marginal setae, and 5–7 median marginal setae ( Fig. 13c). Parameres very slender, lower endomere narrow and mesomere slender, almost triangular ( Fig. 13d). No apertures visible on distal third of parameres. Posterior margin of apodemal bridge more clearly demarcated than anterior margin.

Diagnosis of material from C. minutilla: As above, with the following exceptions:

Pterothorax and abdomen generally narrower, and on the whole shorter ( Table 1). Posterior margin of head markedly concave ( Fig. 14a). Marginal carina very distinct. Hyaline margin visible only in anterior end, and very narrow or missing antero-laterally. Ventral anterior plate almost triangular. AVS3 markedly anterior to AVS2, but both posterior to ADS. PCS very small.

Abdominal sides virtually parallel, and re-entrant heads of tergites more or less completely overlapping with paratergal plate in front ( Fig. 14b). Median margins of paratergal plates and dark border marking clearly delimited, and giving the appearance of a pair of dark “railway tracks” running along the abdomen. Re-entrant tergal heads not always as dark as border markings. Anterior sublateral indentation largely overlapping with paratergal plates and may appear to be missing in some segments. Spiracle openings positioned above the paratergal plate.

Female genital lobes narrow and pointed, with 3 posterior marginal setae, 2 sub-marginal setae, and 5 median marginal setae ( Fig. 14c). Parameres slender, with somewhat rectangular heads ( Fig. 14d). Apodemal bridge vaguely delimited.

Discussion: Using molecular data, Gustafsson and Olsson (2012) showed that the Lunaceps on smaller sandpipers and stints form two geographically widely distributed clades, one in the Palaearctic and one in the Nearctic. Material in that study nominally belonging to L. incoenis was placed in the Palaearctic clade 1, whereas the Nearctic clade 4 included L. pusillus and L. cabanisi . However, naming the Palaearctic clade as L. incoenis is problematic for reasons outlined below.

L. incoenis was described ( Kellogg and Chapman, 1899) from Pluvialis squatarola . However, the holotype —a single female—is generally considered a straggler from an unidentified species of Calidris ( Timmermann, 1954a; Emerson, 1972; Ledger, 1980). Timmermann (1954a) proposed Calidris temminckii as the most likely original host and C. minuta as a secondary host, both based on agreement with measurement between the NHML material from these species and the type of L. incoenis . Ledger (1980) recommended that Timmermann’s (1954a) interpretation should be accepted “for reasons of stability”. However, both of these hosts are Palaearctic, and considered rare accidentals in Alaska with very few records in the Pacific Northwest ( Paulson, 1993). This makes them unlikely original hosts for a louse collected in California.

The holotype of L. incoenis is very old and in poor condition, making many characters of the head difficult to see, thus making certain identification difficult. The AVS3 is anterior to the AVS2, as in much of the material from North American hosts, whereas the tergal heads of abdominal segment VII are intermediate between those of L. falcinellus and those of L. cabanisi . Paratergal bars are narrow, and the posterior margin of the head is slightly concave, as in other North American material, but unlike that of the Palaearctic hosts.

As no Lunaceps have been found on Pluvialis squatarola examined in Sweden (n = 8), and there has been no further records of Lunaceps from this host to our knowledge, we agree with earlier authors ( Timmermann, 1954a; Emerson, 1972; Ledger, 1980) that the holotype is most likely a straggler. In the light of the morphological correspondence between the holotype and other North American material, we conclude that L. cabanisi and L. incoenis represent the same species, and that the former is a junior synonym of the latter.

L. incoenis is similar to L. falcinellus , but can be separated by the shape of the tergal heads of abdominal segment VII, which are narrow and pointed in L. incoenis and broader and blunter in L. falcinellus . There are other minor differences, but most of them fall within the variation within each separate species. In many L. incoenis , the AVS3 is positioned anterior to the AVS2, which only rarely happens in L. falcinellus . The posterior margin of the head is often flatter in L. falcinellus than in L. incoenis . Further, the paratergal bar is generally broader in L. falcinellus than in L. incoenis .

Carriker (1956) stated that his L. pusillus ex Calidris pusilla might closely resemble L. cabanisi , for which he had no material to compare with. Gustafsson and Olsson (2012) found populations of Lunaceps on C. mauri , C. minutilla and C. pusilla genetically identical. The holotype of L. pusillus is longer than Timmermann’s (1954a) measurements for L. cabanisi , but other measurements correspond well between the two species, and we have found no consistent morphological differences between them.

Material from C. minutilla is enigmatic, as there are several morphological differences between this population and material from other hosts. They can readily be separated in a dissection microscope by the intensity of the dark “railway track”-like paratergal plates along the abdominal sides, the shape of the female genital lobes, and the narrower body. However, the two populations are genetically identical ( Gustafsson and Olsson, 2012), and many of the structural differences between them can be ascribed to the narrower abdomen in specimens from C. minutilla , which could be the result of living on a smaller host ( Message and Taylor, 2005). The space between the feather barbs may be smaller in C. minutilla than in other host species, but we have no data on this character. This difference, if present, may explain the morphological differences without corresponding genetic difference. Other explanations may include recent divergence or a history of hybridization. We feel it is prudent for now to keep the two populations within the bounds of one species until more is known about their relationships and the plasticity of body shapes in Lunaceps .

Etymology: From in = not, and coen = common. Possibly a reference to the fact that only a single female was found on the host.

Material examined:

Ex Pluvialis squatarola (in error?)

Holotype: ♀ 1, United States: California: Pacific Grove ( EMEC).

Ex Calidris mauri (synonyms: Ereunetes mauri , Calidris pusillus mauri ) Holotype of L. cabanisi : ♂ 1, United States: California, February 1939, Meinertzhagen Collection 12760-61 ( NHML).

Allotype of L. cabanisi : ♀ 1, United States: California, February 1939, Meinertzhagen Collection , 12760-61 ( NHML).

Paratypes of L. cabanisi . ♀ 8, ♂ 12, United States: California, February 1939, Meinertzhagen Collection 12760- 61, 12840-41, 12948 ( NHML) . ♀ 1, ♂ 1, United States: California, February 1939, K.C. Emerson Collection ( OSU) .

Non-types: ♀ 3, United States: California, May 1923, Meinertzhagen Collection 4301 ( NHML) . ♂ 1, United States: Utah: Toole County: Dugway Proving Ground: Dog Area , 16 July 1958, K.C. Emerson Collection ( OSU) . ♀ 1, ♂ 1, United States: Alaska: Anchorage , 22 May 1962, K.C. Emerson Collection ( OSU) . ♀ 1, United States: Florida: Sanibel , 12 June 1982, K.C. Emerson Collection ( OSU) . ♀ 2, ♂ 2, United States: Utah: Toole County: Skull Valley , 12 August 1954, K. C: Emerson Collection ( OSU) . ♀ 3, ♂ 2, United States: Utah: Toole County: Sewerline , 22 April 1953, K.C. Emerson Collection ( OSU) . ♂ 1, Canada: British Columbia: Vancouver Area: Boundary Bay , 10 July 2009, ID: 1484, Band number: 1401-64523, D. Gustafsson ( SMNH) . ♂ 1, Canada: British Columbia: Vancouver Area: Boundary Bay , 10 July 2009, ID: 1487, Band number: 1401-64530, D. Gustafsson ( SMNH) . ♂ 1, Canada: British Columbia: Vancouver Area: Boundary Bay , 30 July 2009, ID: 1586, Band number: 1401-65712, D. Gustafsson ( GNM) . ♂ 1, Canada: British Columbia: Vancouver: Simon Fraser University , 29 July 2008, ID: 591, Band number: not recorded, YIO-P-01160, D. Lank ( YIO) .

Ex Calidris pusilla (synonym: Ereunetes pusillus )

♀ 4, ♂ 6, Suriname: Paramaribo, 6 September , 1971, BM1973-561 ( NHML) . ♀ 1, ♂ 1, Suriname: Paramaraibo , 8 January 1971, BM 1973-561 ( NHML) . ♀ 3, ♂ 3, Trinidad and Tobago: Trinidad: Fernandez Factory , 30 October 1959, TRVL3402 etc. BM1961-606 ( NHML) . ♀ 2, ♂ 1, United States: New York: Jamaica, 17 September 1944, K.C. Emerson Collection ( OSU) . ♀ 3, ♂ 3, United States: Indiana: Hamilton County, 1 September 1962, K.C. Emerson Collection ( OSU) . ♀ 2, ♂ 2, United States: Texas: Galveston, K.C. Emerson Collection ( OSU) . ♀ 1, ♂ 1, United States: Alaska: Cape Thompson , 22 July 1960, K.C. Emerson Collection ( OSU) . ♀ 3, ♂ 4, United States: Mississippi: Pascaguola , 27 August 1937, K.C. Emerson Collection ( OSU) . ♂ 1, Canada: British Columbia: Vancouver Area: Boundary Bay , 10 July 2009, ID: 1489, Band number: 1401-64531, D. Gustafsson ( SMNH) . ♀ 1, Canada: British Columbia: Vancouver Area: Boundary Bay , 29 July 2009, ID: 1545, Band number: 1401-65702, YIO-P-01161, D. Gustafsson ( YIO) . ♂ 1, Canada: British Columbia: Vancouver Area: Boundary Bay , 17 July 2009, ID: 1499, Band number: 1401-64565, D. Gustafsson ( GNM) . ♂ 1, Canada: British Columbia: Vancouver Area: Boundary Bay , 29 July 2009, ID: 1544, Band number: 1401-65703, D. Gustafsson ( GNM) .

Ex Calidris minutilla

♀ 2, ♂ 2, Canada: Saskatchewan: Aberdeen, 17 September, 1957, R . Connell , BM 1959-376 ( NHML) . ♀ 1, ♂ 2, Canada: Labrador : Turnavik, H. Lance ( NHML) . ♂ 1, Canada: British Columbia: Vancouver Area: Boundary Bay , 17 July 2009, ID: 1491, Band number: 1401-64552, D. Gustafsson ( SMNH) .). ♂ 1, Canada: British Columbia: Vancouver Area: Boundary Bay , 17 July 2009, ID: 1494, Band number: 1401-64558, D. Gustafsson ( SMNH) .

Ex Tringa melanoleuca (possibly stragglers):

♀ 2, Canada: Manitoba: Whitewater Lake , 27 August 1996, Coll. T . D. Galloway / D. Wytrykush / L.M. Babey ( MONZ) .

Ex Tringa flavipes (possibly stragglers):

♀ 1, Canada: Manitoba: Whitewater Lake , 27 August 1996, Coll. T . D. Galloway / D. Wytrykush / L.M. Babey ( MONZ) .

Material of uncertain status due to poor condition:

Ex Calidris mauri (synonym: Ereunetes mauri )

♀ 2, ♂ 1, United States: Alaska: Cape Thompson , 2 August 1960, K.C. Emerson Collection ( OSU) .