SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8422fbc3f9befc4fca8b5f58e891cea810fda8db0987a89c037112418b480afa' 
  AND token = 'TF8USiaWLPFRBmSg8TeLA/n3/cbHGqwaYxPLPvgVoUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}