Creophilus huttoni, (BROUN) STATUS RESUR.

Clarke, Dave J., 2011, Testing the phylogenetic utility of morphological character systems, with a revision of Creophilus Leach (Coleoptera: Staphylinidae), Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 163 (3), pp. 723-812 : 794-796

11. CREOPHILUS HUTTONI (BROUN) STATUS RESUR.

( FIGS 1B, 5C , 33B, E, H, O, Q , 35 )

Staphylinus huttoni Broun, 1880: 108 . Type locality: ‘near Dunedin’; Fauvel, 1885: 312; Hutton, 1904: 183; Hudson, 1923: 362; Tillyard, 1926: 209, pl. 17, fig. 27, text-fig. R37; Hudson, 1934: 180; Gourlay, 1950: 186 (synonym of C. oculatus , attributed to W.O. Steel, p. 202).

Creophilus huttoni ; Walker, 1904: 125; Herman, 2001b: 3325 (synonym of C. oculatus ).

Creophilus Huttoni ; Bernhauer & Schubert, 1914: 398.

Type material: Staphylinus huttoni Broun. Holotype (by monotypy). ♂, ‘200./ [circular with red border] Type/ Otago.| – Hutton/ New Zealand.| Broun Coll.| Brit. Mus.| 1922–482./ Creophilus | huttoni./ [circular with red border] Holo-| type/ FMNH-INS 0000 016 778/ [red] HOLOTYPE | Staphylinus | huttoni Broun, 1880 | teste D.J. Clarke 2008’ (in BMNH). ‘near Dunedin’ (in Otago) is not on any label of the holotype, but the pronota of other BMNH males do not have ‘indistinct impressions before the middle’ as Broun stated, and which are present on the holotype; other specimens in Broun’s collection are females.

Other material examined: 220 specimens. See supporting information, Appendix S1.

Diagnosis: With characters of the erythrocephalus - group; temporal regions and postgena yellowish to reddish-brown, rest of body variegated reddish-brown to brownish-black; apex of antennomere 11 produced into distinct ridge; brachypterous ( Fig. 33O ); last protarsomere much longer than preceding two together; elytral discal series with two macrosetae; tergal chaetotaxic formula = 4-6-6-6-4(6)-6.

Description: Measurements (N = 10♂, 10♀). Forebody length: ♂ 5.5–8.5 mm, ♀ 6.0– 7.8 mm. See supporting Table S5 for comparison of ranges of male and female ratios. Head. Head ( Fig. 33B ) between eyes usually variegated reddish-brown to uniformly dark brown or black, often with diffuse medial lighter patch, or variegated patterning (e.g. Fig. 1B), yellowish or almost red (in darker specimens) behind eyes and on postgena; shorter and narrower in females and subequal in males to pronotum (HL/ PL = 0.6–0.79, HW/ PW = 0.83–1.12), transverse ( HW /HL = 1.29– 1.63); eyes moderately large ( EYL /HL = 0.41–0.55), dorsolateral, lateral margins of head visible in dorsal view (not obscured by eye); HL1/HL2 greater in females than males (♂ = 1.25–1.83, ♀ = 1.71–2.20); antennomeres 1–6 reddish-brown, 7–11 lighter yellowish-brown; mandibles moderately longer than head in large males, subequal to or shorter than head in females ( ML /HL ♂ = 0.94–1.22, ♀ = 0.9–1.06), right mandible with three teeth, T 3 largest, T 1 reduced in smaller specimens; left mandible with distal tooth projecting from base of mandibular blade. Thorax and abdomen. Pronotum ( Fig. 33E ) slightly transverse ( PW / PL = 1.00–1.18), variegated reddishbrown to uniformly dark brown; distinctly longer than elytral suture ( PL 1.45–1.76 ¥ ESL; elytra reddish brown, moderately densely covered in golden-brown vestiture; brachypterous, wings short ( Fig. 33O, Q ), clear yellowish-brown without distinct spot in medial field, non-functional; mesoventral intermesocoxal process moderately to distinctly obtusely angulate ( Fig. 33H ), often produced into short subacuminate apex; metaventrite broadly flattened, occasionally with small posteromedial tumescence near hind margin; protibiae always with outer row of spines (as in Fig. 33M ); last protarsomere much longer than preceding two together (as in Fig. 33J ); abdomen uniformly reddish-brown to brownish-black; tergite VII with at most poorly developed palisade fringe. Male genitalia. Aedeagus indistinguishable from that of C. oculatus , see Figure 32C and D . Female genitalia. Internal female genitalia as in Figure 5C ; vaginal plate (vp) without median sclerotized strip, with paired lateral sclerites (pls), posterolateral aspects membranous; vaginal fold (vf) with single large sclerite, finely rugosely sculptured. Chaetotaxy. Elytral discal series with two macrosetae; protrochanter with two macrosetae, mesotrochanter with one macroseta; tergal chaetotaxic formula = 4-6-6-6-4(6)-6; medial macrosetae absent from tergite III, inner lateral macrosetae present or absent on tergite VII.

Variation: Creophilus huttoni varies in colour from very light mottled brown with darker patches on the head and pronotum through to uniformly dark reddish-brown. The latter specimens occasionally also lack the abrupt change to yellowish or reddish at the temples (the normal pattern in both C. huttoni and C. oculatus ), but this is rare. The pronotum of this species is only subtly different from that of C. oculatus , usually with straighter sides, and varies somewhat with size.

Comparison: Creophilus huttoni may co-occur with C. oculatus on sandy beaches where it is found, and no apparent differences between aedeagi of C. huttoni and C. oculatus specimens were observed. They are externally distinguishable by general habitus and (usually) coloration. Creophilus huttoni also has the following morphometric characters: more quadrate pronotal shape, shortened and narrower elytra, obtusely angulate mesoventral process ( Fig. 33H ), and reduced, non-functional wings ( Fig. 33O, Q ). Figure 33Q clearly illustrates a discrete difference in wing development between these two species.

Distribution ( Fig. 35 ): New Zealand (South Island): Otago Peninsula, south to Stewart Island and surrounding islands. One specimen in CMNZ ( FMNH- INS 0000 017 658) is labelled from Kaitaia (North Island: ND), but is probably mislabelled.

Biology and ecology: Creophilus huttoni is an obligate beach- and dune-inhabiting species, found beneath drier seaweed, particularly older buried algal holdfasts high above the strand line. Specimens have been taken from beach drift, in wrack, supralittoral logs, and under bull kelp, rocks, and debris. It is found mainly on sandy beaches, but seems abundant only where there is a wide supralittoral zone (pers. observ.). I collected and observed many specimens live during December 2005 and found them to be flightless (see description of observations of attempted flight in C. rekohuensis , below). Like the related intertidal species Thinopinus pictus ( Richards, 1982) , the major food source appears to be amphipods, and these were abundant above the strand line. Maggots or other larvae were most abundant in fresher seaweed lower on the shore where Cafius was very abundant, but C. huttoni rare. I intercepted one specimen as it was feeding on an amphipod, and fed several specimens amphipods for more than a week. Larvae were found in hollowed-out sand galleries, particularly beneath algal holdfasts above the strandline (pers. observ.). A few specimens discharged an unpleasant smelling white substance from the abdominal defence glands when threatened. Phenology: January–April, August–December. Larvae are known and will be described elsewhere. Pupae are unknown.

Remarks: The pronotal ‘impressions’ noted by Broun (1880) are not unique to C. huttoni , so are diagnostically useless. Gourlay (1950: 202) acknowledged W. O. Steel for the synonymy of C. huttoni with C. oculatus , and Steel’s advice is likely to have been based on a comparison of aedeagi, which are qualitatively indistinguishable. In addition to characters cited above, the restricted distribution of C. huttoni and the unusual beach-dwelling ecology supports the reinstatement of C. huttoni to a valid species. Future work on this species should incorporate molecular data and the powerful tools of geometric morphometrics, and should attempt captive rearing and breeding experiments.

Figures

Figure 5. Female genitalia, details of morphology (all but E, ventral view). A, Creophilus m. villosus, internal genitalia; B, C. erythrocephalus, internal genitalia; C, C. huttoni, internal genitalia; D, C. oculatus, gonocoxites and styli (setae omitted from left side); E, Thinopinus pictus, abdominal segments VIII–X, dorsal (vestiture omitted); F, T. pictus, internal genitalia; G, Staphylinus caesareus, internal genitalia; H, Platydracus maculosus, internal genitalia; I, Hadrotes crassus, right gonocoxites and stylus (vestiture omitted) – arrow indicates membranous articulation; J, T. pictus, right gonocoxite. Abbreviations: bcx, bursa copulatrix; fl, flagellum (note that the complete structure is not shown); gc, gonocoxite; gcm, gonocoxal macroseta; gc1, gonocoxite I, gc2, gonocoxite II; mg, median groove; pls, paired lateral sclerites of vaginal plate; sc, sclerite of bursa copulatrix; sd, spermathecal duct; sp, spermatheca; ss, sclerotized strip of vaginal plate; sty, gonostyle; vf, vaginal fold; vp, vaginal plate. Scale bars = 1 mm.

Figure 32. Creophilus oculatus, details of morphology (setae of mandibles, antenna, and pronotum omitted). A, mandibles, dorsal (bases omitted); B, right antenna, dorsal (only apical setae shown); C, aedeagus with details of inverted internal sac, ventral; D, same, right lateral (parameral setae omitted); E, ventral sclerite of internal sac, ventral (lower) and apical (upper); F, pronotum (female); G, female internal genitalia, ventral; H, paramere, dorsal; I, median lobe apex, ventral. Abbreviations: T1, T2, T3, mandibular teeth. Additional abbreviations as in Figure 3 (male) and Figure 5 (female). Scale bars: E = 0.1 mm; rest = 1 mm.

Figure 33. New Zealand Creophilus species, details of morphology (setae of heads, pronota, mesoventrites, and legs omitted). C. oculatus (A, D, G, J, M, N); C. huttoni (B, E, H, O); C. rekohuensis, holotype (C, F, I, K, L, P). A–C, head, dorsal; D–F, pronotum; G–I, mesoventrite; J, K, protarsus, dorsal; L, M, right protibia, anterior; N–P, left wing, dorsal; Q, scatter plot of wing length vs. pronotum length as proxy for body size (circles = C. oculatus, squares = C. huttoni, triangles = C. rekohuensis; black symbols = males, white symbols = females). Abbreviations: CuA, MP3, MP4, wing veins mentioned in text. Scale bars = 1 mm.

Figure 35. Distribution of all georeferenced specimens of C. huttoni in southern New Zealand (circles). For location of map within New Zealand see rectangle in Figure 34.