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Taxonomy


Family-level taxonomy of the Delphacidae
Delphacids are in the insect order Hemiptera.  The Hemiptera are characterized in part by having piercing/sucking mouthparts (which lack palpi and with mandibular and maxillary stylets enclosed within a multi-segmented labial sheath), and simple metamorphosis (hemimetabolous, with the immatures and adults similar in form, and occupying the same habitat).  Traditionally, however, delphacids were considered to be in the order Homoptera (“same-wing”, a reference to the uniform texture of the front wings), but recent study have concluded that the true bugs (the Heteroptera [“varied-wing”], the old “Hemiptera”) are closely related and should be combined into a single order.  For this reason, modern authorities now combine the old orders “Homoptera” and the true bugs (the old “Hemiptera”) to form a single order, which is called Hemiptera for historic reasons.  The combined order Hemiptera is the 5th largest order of insects with nearly 90,000 described species.

 Within the Hemiptera, the delphacid planthoppers are in the suborder “Auchenorrhyncha” (“neck-beaked” a reference to the position of their mouthparts).  The validity of the Auchenorrhyncha as a suborder (i.e., its monophyly) has been questioned, but current evidence strongly suggests that it is a good, natural group.  The Auchenorrhyncha are mostly jumping insects, with uniformly textured wings (as opposed to the true bugs), 3 segmented tarsi, and generally hard-bodies (as opposed to aphids and scale insects).  Also, the antennae of Auchenorrhyncha is 3-segmented, with the last segment long and bristle like (most true bugs, aphids and psyllids have longer antennae).

Within the Auchenorrhyncha, there are groupings, usually treated as infraorders:  the Cicadomorpha (cicadas, leafhoppers, treehoppers, spittlebugs) and the Fulgoromorpha (planthoppers and lanternflies).  These groups are most readily separated by features of the head.  The Fulgoromorpha have their antennae located below their eyes in side view (as opposed to in front of the eyes), and have distinct ridges (“carinae”) on the face, in particular a pair that separates the side of the head from the front of the head, but frequently one that follows the midline of the face.  The position of the simple eyes (“ocelli”) and the general form of the antennae are different also.  Compared to the “Cicadomorpha”, planthoppers have more conspicuous antennae (particularly in Delphacidae), which bear sensory plaques and arise beneath the eyes (with rare exceptions), the lateral ocelli are near the compound eye, located at or below the middle of the compound eyes, and the face with 2 to 5 longitudinal ridges (carinae).  In planthoppers, the median ocellus is absent or (some cixiids) located just above the clypeus (see figure).

The cicadomorph families have less conspicuous antennae (without sensory plaques) that arise in front (anterior) of the compound eyes, ocelli (including median ocellus, when present) located above the middle of the compound eyes (sometimes on top of the head, as in cicadas and others), and the face without longitudinal ridges (i.e., no carinae), but may have grooves (sulci) or an enlarged clypeus exhibiting a grill-like pattern.

The infraorder Fulgoromorpha consists of a single extant superfamily, the Fulgoroidea (dating from the early Jurassic), and two extinct superfamilies the Coleoscytoidea and the Surijokocixioidea (dating from the late Permian or early Triassic.  The superfamily Fulgoroidea consists of about 21 families and 12,000 species worldwide, dependent on the taxonomy used.  Of these families, 16 can be found in the New World, and 13 north of Mexico.  Most of these families do not have common names and are all referred to as “planthoppers” or in combination with the scientific family name, hence “delphacid planthoppers”, “cixiid planthoppers”, “flatid planthoppers” and so on.  Alternately, they can be referred to by the shortened family name “delphacids”, “cixiids”, "flatids” and so on.  The lanternflies (the Fulgoridae, see http://www.planthopper.com/index.html) are a group of relatively large, mostly tropical planthoppers, whose common name is derived from the mistaken belief that they are bioluminescent.

For Delphacidae, the status of the higher groupings is discussed under "systematics".  A summary of the number of species in each of the higher groupings is below.

 

Higher Classification and numbers of species of the Delphacidae (Asche 1985, 1990)

Taxon

# genera

# species

% genera

% species

“Asiracinae”: Asiracini

10

28

3.5

1.5

         Ugyopini

13

148

4.6

8.1

Vizcayinae

1

5

0.4

0.3

Kelisiinae

2

44

0.7

2.4

Stenocraninae

4

64

1.4

3.5

Plesiodelphacinae

2

7

0.7

0.4

Delphacinae: Tropidocephalini

21

122

7.4

6.6

        Saccharosydnini

3

9

1.1

0.5

        Delphacini

227

1,088

80.2

59.2

Incertae sedis

22

323

---

17.6

Totals

283

1,838

100.0

100.0

 

Number of genera and species of New World Delphacidae

Higher taxon

Nearctic

Neotropical

All New World

 

(#genera/#species)

Asiracinae

2/6

11/48

8/52

Plesiodelphacinae

0/0

2/7

2/7

Kelisiinae

1/12

1/1

1/12

Stenocraninae

3/16

4/10

5/24

Delphacinae: Saccharosydnini

1/1

3/9

3/9

Delphacinae: Tropidocephalini

0/0

5/20

2/20

Delphacinae: Delphacini

54/303

44/209

73/446

Total

61/338

67/304

100/571

Kelisia vittata Muir, 1926 is misplaced at the genus and tribal level.