Strumigenys, F. Smith, 1860

Booher, Douglas B., Prebus, Matthew & Lubertazzi, David, 2019, A taxonomic revision of the Strumigenys nitens and simulans groups (Hymenoptera: Formicidae), two Caribbean radiations of leaf litter ants, Zootaxa 4656 (2), pp. 335-358 : 355-356

Key to the workers of Hispaniolan Strumigenys :

With the description of S. zemi and S. economoi , the Hispaniola ant fauna now consists of eleven species ( S. economoi , S. eggersi , S. emmae , S. gundlachi , S. lanuginosa , S. louisianae , S. membranifera , S. nigrescens , S. rogeri , S. silvestrii , and S. zemi ). What is known about the biology and distribution of the non- nitens group species from the island is detailed in The Ants of Hispaniola ( Lubertazzi, 2019). Here we provide a key to the Strumigenys of the island.

1 Dorsum of pronotum without sculpture.................................................................... 2

- Dorsum of pronotum variously sculptured, at least some striations or punctuation.................................. 4

2 Dorsum of head smooth and shining medially and posteriorly; propodeal spines present; darker brown species........... 3

- Dorsum of head heavily punctate over entire surface; propodeum without spines; dull and light orange....... membranifera

3 Mandibular teeth elongate and spiniform with first two teeth not overlapping or interlocking when shut........ zemi sp. nov.

- Mandibles with small, conical, serially dentate teeth that interlock when shut......................... economoi sp nov.

4 In full face view mandibles shorter (MI ≤ 25), with a series of alternating, bluntly rounded, triangular teeth that interlock in closed position; outline of mandibles triangular...................................................... nigrescens

- In full face view mandibles longer (MI ≥ 26 and usually much longer, MI>50), meeting only at the distal tip, never with a basal series of interlocking teeth in closed position; outline of mandibles not triangular................................... 5

5 Antenna with 4 segments; in full face view mandibles strongly convex, bow-like, with a single pair of long spiniform teeth, just distal to midpoint of mandible, that are much longer than the maximum width of mandible; mandibles relatively short (MI ≤ 40). In full frontal view, entire dorsal surface of head and anterior margin of scape with apically expanded, orbicular setae................................................................................................. emmae

- Antenna with 6 segments; In full face view mandibles elongate (MI> 50), linear, and not bow-like; without spiniform teeth near midpoint of mandible; setae on head and scape fine to spoon-shaped, but never orbicular............................ 6

6 Petiole, postpetiole, and gaster with abundant, long, filiform to flagellate setae; absent of shorter laterally expanded clavate setae; dorsal margin of antennal scrobe with two long flagellate setae, one at mid-scrobal position just above the compound eye and another at apicoscrobal position.............................................................. lanuginosa

- Erect setae, when present on the petiole, postpetiole, or gaster, are short and stiff and/or laterally expanded, never flagellate; erect scrobal setae, when present, are limited to a single pair of clavate to flagellate setae in apicoscrobal position......... 7

7 Setae on leading edge of scape all curve away from the base of the scape; petiole with ventral spongiform tissue; mandibles with two preapical teeth arising in the distal third of mandibles and subequal in length to the width of the mandibles at the point at which they arise.................................................................................. rogeri

- Setae on leading edge of scape with one to many setae that curve toward the base of the scape; petiole without ventral spongiform tissue; if more than one preapical tooth or denticle is present, they never approach the width of mandibles where they arise................................................................................................ 8

8 Entire surface of first gastral tergite punctate to reticulopunctate; postpetiole in profile with the ventral spongiform lobe absent or reduced to a minute nonspongiform vestige and without lateral flange of spongiform tissue................... eggersi

- Surface of first gastral tergite without punctate sculpture, or if present, punctate sculpture is limited to the anterior margin; postpetiole in profile with ventral and lateral spongiform tissue present........................................... 9

9 Dorsum of head covered with broadly spatulate to spoon-shaped setae; mandibles with a single preapical tooth arising just anterior of apical tooth; without denticles........................................................... louisianae

- In full face view, setae present across anterior portion of the head and leading edge of scape are curved and flattened or expanded apically, but are not spatulate or spoon shaped; mandibles with at least two preapical teeth or denticles on the distal halves of mandibles.................................................................................. 10

10 In full face view, mandibles long with linear to slightly concave outer margin; distal half of mandibles with 4-9 preapical teeth (may be difficult to see); eye larger, usually with 5-6 ommatidia......................................... gundlachi

- In full face view, mandibles long and noticeably convex along their outer margin; two preapical teeth present, one near the midpoint of mandibles and one positioned just anterior the dorsoapical tooth; eye small usually with 4 or less ommatidia................................................................................................. silvestrii