Linepithema flavescens

Little is known about the biology of this species. It has been collected twice in Haiti. The type series was collected by Mann from “under a stone on a dry hill-side” in Cape Haitien. The only non-type specimens were found in the northeast hills of the Massif de La Hotte (col. Darlington 1934). Morphological characters (short appendages, small eyes, pale color) suggest a hypogeic existence.

Identification
Wild (2007) - Workers of Linepithema keiteli, a commonly encountered Hispaniolan endemic, are closely similar in structure but have larger eyes ( > 40 ommatidia), longer scapes (SI > 90), more standing pilosity on the gaster, and are generally darker in color. Workers of Linepithema cryptobioticum, a compact pale-colored ant from South America, have smaller eyes ( < 25 ommatidia), a greater separation of the frontal carinae (CDI > 30), and a strongly elevated propodeum.

Males have not been collected, but they will probably key out near L. keiteli. Worker specimens from Massif de La Hotte are considerably less pilose and have slightly smaller eyes (OI < 14) than specimens from the type locality at Cape Haitien.

Distribution
Hispaniola.

Distribution based on Regional Taxon Lists
Neotropical Region: Greater Antilles, Haiti.

Castes
The queen and male are unknown.

Nomenclature

 *  flavescens. Iridomyrmex keiteli var. flavescens Wheeler, W.M. & Mann, 1914: 43 (w.) HAITI. Combination in Linepithema: Shattuck, 1992a: 16. Raised to species: Wild, 2007a: 49.

Worker
Length 2-2.3 mm.

Differing from the typical keiteli in its slightly larger size and in coloration, the whole body being clear yellow, except the mandibular teeth, which are black, and the occipital impression of the head, which is very feebly infuscated.

Wild (2007) - Lectotype worker measurements: HL 0.71, HW 0.71, MFC 0.19, SL 0.58, FL 0.56, LHT 0.55, PW 0.46, ES 1.28, SI 81, CI 101, CDI 27, OI 18.

Worker measurements: (n = 7) HL 0.64–0.72, HW 0.64–0.71, MFC 0.17–0.19, SL 0.54–0.58, FL 0.49–0.56, LHT 0.52–0.59, PW 0.43–0.46, ES 0.75–1.27, SI 81–85, CI 95–101, CDI 27, OI 11–18.

Worker diagnosis: Antennal scapes short (SI 81–85); eyes with < 40 ommatidia; promesonotum strongly convex and relatively broad, mesonotum in lateral view meeting dorsal face of propodeum at an angle of 90°–100°; color pale yellow.

Worker description: Head in full face view about as broad as long (CI 95–101), lateral margins convex, posterior margin strongly concave. Compound eyes small (OI 11–18), comprised of 28–40 ommatidia. Antennal scapes shorter than head length (SI 81– 85). In full face view, scapes in repose approximately reach posterior margin of head. Frontal carinae moderately spaced (CDI 27). Maxillary palps of moderate length, approximately 1⁄2 HL, ultimate segment (segment six) subequal in length to segment 2.

Mesosoma in lateral view with pronotum and mesonotum forming a single continuous convexity, mesonotum strongly convex, without central saddle or indentation, and meeting dorsal propodeal face at an angle of 90°–100°. Metanotal groove slightly impressed, propodeum depressed well below level of mesonotum. Propodeum in lateral view rounded, posterior margin convex dorsad of the metapleural bulla. In dorsal view, mesosoma relatively broad (PW 0.43–0.46).

Petiolar scale inclined anteriorly, in lateral view falling short of propodeal spiracle.

Cephalic dorsum (excluding clypeus) lacking erect setae. Pronotum with 0–4 erect setae (mean = 1.3). Mesonotum without erect setae. Erect setae on gastric tergites 1–4 ( = abdominal tergites 3–6) relatively sparse, tergite 1 bearing 10 erect setae of varying length. Venter of metasoma with scattered erect setae.

Sculpture on head and pronotal dorsum lightly reticulate-punctate and only slightly shining. Pubescence dense on head, propodeal dorsum, anterior petiolar scale, and gastric tergites 1–4. Mesonotal dorsum with moderate pubescence fading to sparse medially. Lateral face of pronotum, mesopleura and metapleural bulla without pubescence and strongly shining.

Color pale yellow.

Type Locality Information
Described from several specimens taken from a nest under a stone on a dry hill-side at Cape Haitien.

Wild (2007) - Lectotype worker, by present designation (, examined), and 5 worker paralectotypes, Cape Hatien, Haiti, W. M. Mann (, examined).

References based on Global Ant Biodiversity Informatics

 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Perez-Gelabert D. E. 2008. Arthropods of Hispaniola (Dominican Republic and Haiti): A checklist and bibliography. Zootaxa 1831:1-530.
 * Shattuck S. O. 1994. Taxonomic catalog of the ant subfamilies Aneuretinae and Dolichoderinae (Hymenoptera: Formicidae). University of California Publications in Entomology 112: i-xix, 1-241.
 * Wheeler W. M., and W. M. Mann. 1914. The ants of Haiti. Bulletin of the American Museum of Natural History 33: 1-61.
 * Wheeler, William Morton. 1936. Ants From Hispaniola and Mona Island. Bulletin: Museum of Comparative Zoology at Harvard College. 80(2):192-211.
 * Wild A. L. 2007. Taxonomic revision of the ant genus Linepithema (Hymenoptera: Formicidae). University of California Publications in Entomology 126: 1-151