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Genus Sialis

Alderfly - Sialis Alderfly - Sialis Alderfly - Sialis Alderfly - Sialis sialid 2 - Sialis Alderfly Larva - Sialis unknown aquatic beetle larvae - Sialis Predatory Beetle Larva? - Sialis
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Megaloptera (Alderflies, Dobsonflies, and Fishflies)
Family Sialidae (Alderflies)
Genus Sialis
Pronunciation
Sigh-AL-is
Synonyms and other taxonomic changes
Two former species of Sialis were transferred to Protosialis (P. americana and P. glabella) by Liu et al. (2015)(1)(2)
Explanation of Names
Sialis Latreille 1802
From Greek sialis (σιαλις) 'a type of bird'(3)
Numbers
22 spp. in our area;(4)(1)(2) 60 worldwide as the most speciose megalopteran genus(5)(6)
1. Sialis aequalis: eastern (CT, DE, GA, KY, MD, ME, MI, MN, NC, NJ, NY, OH, PA, SC, VA, VT, WV)
2. Sialis arvalis: western (CA & OR)
3. Sialis bilobata: CA
4. Sialis californica: western (Canada: AB, BC; United States: CA, OR, WA)
5. Sialis concava: primarily north(eastern) (Canada: BC, ON; United States: MD, ME, NC, NY, VA, WV)
6. Sialis contigua: eastern (TN & VA)
7. Sialis cornuta: northern (Canada: AB; United States: ID, MT, OR, WA, WY)
8. Sialis dreisbachi: northeastern (MI, MN, WI)
9. Sialis hamata: western (Canada: AB, BC; United States: ID, MT, NV, OR, UT, WA, WY)
10. Sialis hasta: eastern (AR, IN, KY, MI, MO, PA)
11. Sialis infumata: eastern (Canada: ON; United States: AR, IL, IN, KS, KY, ME, MI, MN, MO, NC, NJ, NY, OH, OK, PA, SC, VA, WI, WV)
12. Sialis iola: eastern (Canada: QC; United States: CT, DC, GA, IN, ME, MS, NC, NH, NJ, NY, ON, PA, SC, VA)
13. Sialis itasca: eastern (Canada: ON, QC; United States: AR, DC, GA, IL, IN, KS, MD, MI, MN, MO, NC, ND, NY, OH, OK, PA, TN, TX, VA, WI, WV)
14. Sialis joppa: eastern (Canada: ON; United States: AR, CT, DE, FL, IL, KY, LA, MD, ME, MI, MO, NC, NH, NY, OH, OK, PA, VA, VT, WI, WV)
15. Sialis mohri: eastern (Canada: NB, ON, QC; United States: AR, CT, IL, IN, KS, KY, MA, ME, MI, MN, MO, MS, NE, NH, NJ, NY, OH, OK, PA, RI, TN, VT, WI)
16. Sialis nevadensis: southwestern (CA & NV)
17. Sialis nina: KY
18. Sialis occidens: southwestern (CA & NV)
19. Sialis rotunda: western (Canada: BC; United States: CA, OR, WA, WI)
20. Sialis spangleri: MD
21. Sialis vagans: eastern (Canada: NB, NS, ON, QC; United States: AR, CT, FL, GA, IL, IN, KS, KY, MA, MD, ME, MI, MN, MO, MS, NC, NH, NJ, NY, OH, PA, VA, VT, WI)
22. Sialis velata: transcontinental (Canada: AB, BC, MD, ON, QC, SK; United States: CO, CT, ID, IL, IN, KS, MA, MD, ME, MI, MN, MO, MT, NC, ND, NE, NH, NJ, NY, OK, TN, TX, UT, WI, WV, WY)
Size
8-18 mm to wingtips(5)(6)
Identification
Black or dark brown insects that hold their heavily-veined wings folded roof-like over their backs. Head primarily black and lacking ocelli. Antennae roughly half the body length. Fourth tarsal segment widened, has two lobes. Wing venation:

Identification of many species requires microscopic examination of male genitalia.
keys to larvae & adults (9 spp.)(7)
Range
holarctic (widespread) and parts of the Neotropics; in our area, S. infumata, S. americana, and S. mohri are widespread; S. infumata represents a species complex(6)
Habitat
Adult typically found on vegetation near larval habitat (streams, ponds)
Larvae prefer soft substrates (mud, silt, detritus) with plant debris accumulations. Many species are associated with specific waterbody types, e.g., S. joppa is found primarily in small streams, S. itasca is associated with lakes, other spp. (such as S. americana, S. vagans) are known from both lakes and streams.(6)
Season
Typically May-Jun in most places, Apr-Jul in NC, Apr-May in KS, as early as Mar in TX(8)
Food
Larvae prey on aquatic invertebrates (chironomids, tubificid worms, ostracods)(5)(6); adults eat little, if at all
Life Cycle
Larvae pupate above water level. Mating at night. Eggs laid near water. Pupae overwinter.
Works Cited
1.Phylogeny of the family Sialidae inferred from morphological data, with implications for generic classification and historical´┐
Xingyue Liu, Fumio Hayashi, & Ding Yang. 2015. Cladistics 31(1): 18-49.
2.Alderflies, fishflies and dobsonflies (Insecta: Megaloptera) of the Interior Highlands, U.S.A.
David E. Bowles and Robert W. Sites. 2015. Transactions of the American Entomological Society, Vol. 141. Issue 3, pp. 405-429.
3.Dictionary of Word Roots and Combining Forms
Donald J. Borror. 1960. Mayfield Publishing Company.
4.Species catalog of the Neuroptera, Megaloptera, and Raphidioptera of America North of Mexico
Penny N.D., Adams P.A., Stange L.A. 1997. Proc. Calif. Acad. Sci. 50: 39-114.
5.Aquatic Insects of North America
R. W. Merritt, K. W. Cummins, M.B. Berg. 2008. Kendall/Hunt.
6.A Guide To The Megaloptera And Aquatic Neuroptera Of Florida
7.Bright E. (2002-2011) Aquatic Insects of Michigan
8.Insects of the Texas Lost Pines (W.L. Moody, Jr., Natural History Series, No. 33)
Stephen W. Taber, Scott B. Fleenor. 2003. M University Press.