SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03a285ac839ad5d079cc2c10fdc022312d22a8d594e93d759dc0980ebf93a335' 
  AND token = 'Ozoy71T1ZdhAyxgN2FuFe8Q3+QiD/ksNN04tnvpteY0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}