SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a202185a770b2feaa843e13100e84d304ebf23999510331e99c377acf35c1579' 
  AND token = '39yFZ3Ao81svRPYl4Ewv/85UpIGfbFEzrueFb65tXPA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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