Amblopusa brevipes Casey

Yoo, In-Seong & Ahn, Kee-Jeong, 2020, Discovery of a new intertidal species, Amblopusa vancouverensis from Vancouver Island, Canada with notes on Amblopusa brevipes Casey (Coleoptera, Staphylinidae Aleocharinae), Zootaxa 4803 (3), pp. 505-514 : 506-509

Amblopusa brevipes Casey

( Figs. 1 , 7–17 , 26–28 )

Amblopusa brevipes Casey, 1893: 356 (original description; TL: Fort Wrangel, Alaska); Fenyes, 1918: 104 (characters: genus; illustrations; Alaska, British Columbia); Bernhauer & Scheerpeltz, 1926: 550 (catalog; Alaska, British Columbia); Moore, 1956: 128, 150 (description; illustrations; British Columbia: Massett); Hatch, 1957: 149 (characters in a key); Moore & Legner, 1975: 339 (catalog; Alaska, British Columbia); Ahn & Ashe, 1995: 139, 143 (description; illustrations; Alaska, British Columbia, California); Zerche, 1998: 106, 107 (characters; habitus photograph of LT); Frank & Ahn, 2011: 25 (worldwide checklist; Alaska, British Columbia, California).

Amblopusa pallida Casey, 1911: 212 (original description; TL: Victoria, Vancouver Island).

Redescription. BL 1.9–2.1 mm, elongate, parallel-sided, somewhat flattened dorsally. Body light brown to brown, abdomen except segment VIII darker. Male. Head round, about 1.1 times as long as wide; lateral margin rounded; dorsal surface flattened, evenly pubescent; microsculpture of dorsal surface imbricate, anisodiametric. Occipital carina more or less linear, complete. Infraorbital carina not developed. Eyes very small with about 5–6 facets, less than 0.2 times of temple length, about 0.1 times as long as HL. Labrum transverse, anterior margin slightly convex. Mandibles ( Figs. 8–9 ) asymmetrical; apices more or less acute and slightly curved downward; slightly different irregular serration on subapical inner margin. Labium ( Fig. 11 ) with ligula rod-shaped, entire at apex; ligula 0.5 times as long as palpomere 1, about 1.3 times as long as palpomere 2; labial palpi with 2 articles, substyliform, palpomere 2 shorter than half length of 1; twin pores present, prementum without pseudopores medially and laterally; setal pores present. Maxilla ( Fig. 10 ) with galea shorter and narrower than lacinia; palpomere 3 dilated apically; internal surface of lacinia with large spine apically, 5 short spines more medially and 1 large spine behind these. Memtum ( Fig. 12 ) trapezoidal, about 0.6 times as long as wide; anterior margin broadly and moderately emarginate; seta v absent. Submentum with numerous punctures and setae; punctation on surface slightly denser than those of mentum. Antenna ( Fig. 7 ) short (about 0.6 mm), increasing in width toward apex, not exceeding posterior margin of pronotum when extended posteriorly; antennomere 1 about 1.1 times as long as 2, 4–6 similar in length, last antennomere about 1.5 times as long as the preceding one; antennomere 4 somewhat round, 5–10 transverse. Neck absent. Pronotum subquadrate, as long as wide; lateral margin sinuate; hypomeron broad. Mesoventral process pointed at apex. Mesocoxal cavities contiguous, posterior margin of mesocoxal cavities not carinate. Elytron about 1.6 times as long as wide, about 0.8 times as long as pronotum; postero-lateral margin linear, not sinuate. Hind wings absent. Hind tarsus slightly longer than half length of hind tibia; relative ratio of hind tarsomeres 1.0: 0.7: 0.7: 0.7: 1.2. Tarsal formula 4-4-5. One empodial seta present, much shorter than claws. Abdomen flattened dorsally and distinctly convex ventrally, widened posteriorly; abdominal tergites III–VII strongly impressed at base; abdominal sternite III with basal carina abruptly V-shaped; abdominal tergite VIII ( Fig. 14 ) with 4 macrosetae on each side of midline, posterior margin straight; abdominal sternite VIII ( Fig. 13 ) with 5 macrosetae on each side of midline, posterior margin prolonged medially. Median lobe ( Fig. 15 ) of aedeagus with apical lobe strongly curved. Paramere of aedeagus as in Figs. 16–17 . Female. Posterior margin of abdominal sternite VIII less prolonged at median region than male. Spermatheca ( Figs. 26–28 ) with duct very short, not coiled.

Material examined. LT ( Figs. 3–4 ), “Ft. Wrangel | Alaska. | Wickham. || CASEY | bequest | 1925 || TYPE USNM | 38771 || Amblopusa | brevipes | Csy || LECTOTYPE | Amblopusa brevipes | Casey. Desig. K. J. Ahn | and J. S. Ashe, 1994 || Zerche rev. 1997” ( NMNH); 3 exx. (1♂ genitalia dissected; 2 genital segments dissected but genital organs missing), “Ft. Wrangel | Alaska. | Wickham. || Dup. N | Casey || o. 131 | 1891 || 20678 || (small golden

round label without letters) || A. Fenyes | Collection || Collection of the | CALIFORNIA ACADEMY | OF SCI- ENCES, San | Francisco, Calif. || Amblopusa | brevipes | Csy. || Amblopusa | brevipes Casey | det. K.-J. Ahn 1994” ( CAS); 1♀ (genitalia dissected), “Ft. Wrangel, | Alaska. | Wickham. || Dupl. No.22 | Fauvel. || Amblopusa | brevipes Csy | det J.S.Ashe 19 || SMO544538 | KUNHM-ENT” ( SEMC); 1 ex., USA: ALASKA, Agattu, 2m el. 52.41932° 173.70123° ± 11m under driftwood, forceps, 5AUG 2010 Derek S. Sikes || UAM 100336064 ( UAM); 1♀ (head separated, slightly cleared; genital segments dissected), ditto || UAM 100336105 ( CNUIC); 1♂ (genitalia dissected), ditto || UAM 100336109 ( CNUIC); 1 ex., ditto || UAM 100336913 ( UAM); 1♂ (on slide), USA: ALASKA, Agattu, 2m el. 52.41932° 173.70123° ± 11m under drift wood, 5AUG 2010 Derek S. Sikes || UAM 100336914 ( CNUIC); 1 ex., ditto || UAM 100336915 ( UAM); 5 exx. (in 100% EtOH, AC1318), CANADA: British Columbia, Vancouver Island, Ucluelet, Wild Pacific Trail, N48°55′39.23″ E125°32′22.74″ 6 m, 16 XI 2018, JH Song, JS Lee, 0–20 cm deep, near log on gravel beach, flotation ( CNUIC); 10 exx. (4 in 100 % EtOH, AC1320), CANADA: British Columbia, Vancouver Is., Ucluelet, Wild Pacific Trail, JH Song, JS Lee, N48°55′26.04″ E125°32′31.86″ 3 m, 16 XI 2018, gravels on pebble beach, flotation ( CNUIC).

Distribution. Canada (British Columbia), USA (Alaska, the Aleutian Islands: Agattu Is., California).

Remarks. We found that the spermatheca and male genitalia of A. brevipes provided by Ahn & Ashe (1995) was incorrectly associated. The median lobe ( Fig. 7 in Ahn & Ashe, 1995) was confirmed to be that of A. brevipes ( Figs. 15–17 ) but the spermatheca ( Fig. 6 in Ahn & Ashe, 1995) was not that of A. brevipes .

In order to solve the problem, we newly dissected the genital segments from three different populations (Agattu Island, Fort Wrangel, and Vancouver) including type locality (Fort Wrangel) of A. brevipes and compared each other. As a result, we conclude that the spermathecae ( Figs. 26–28 ) are those of A. brevipes but we do not know which species the spermatheca ( Fig. 6 in Ahn & Ashe, 1995) belongs to.

Figures

FIGURES 1–2. Adult habitus. 1: Amblopusa brevipes, 2.1 mm; 2: A. vancouverensis, holotype (male, abdominal segment VIII including genitalia dissected), 1.6 mm.

FIGURES 7–12. Amblopusa brevipes. 7: antenna; 8: mandible, left, dorsal aspect; 9: mandible, right, dorsal aspect; 10: maxilla, right, ventral aspect; 11: labium, ventral aspect; 12: mentum, ventral aspect. (scales: 0.05 mm for 8–9; 0.1 mm for 7, 10–12)

FIGURES 13–17. Amblopusa brevipes. 13: male abdominal sternite VIII, ventral aspect; 14: male abdominal tergite VIII, dorsal aspect; 15: median lobe of aedeagus, lateral aspect; 16: paramere of aedeagus, lateral aspect; 17: apical lobe of paramere. (scales: 0.1 mm)

FIGURES 26–29. Spermathecae. 26–28: Amblopusa brevipes (26, from Agattu Island; 27, from Vancouver Island; 28, from Fort Wrangel, Alaska); 29: A. vancouverensis.

FIGURES 3–4. Lectotype of Amblopusa brevipes. 3: habitus, male; 4: labels.

FIGURES 5–6. Type locality of Amblopusa vancouverensis. 5: Ucluelet, Wild Pacific Trail, Vancouver Is., Canada; 6: microhabitat: 0–20 cm deep, gravel beach.