SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1afa1b1286b7243b1cc9fcc1518b95f4dae98bb608109a108833c1c6da438f29' 
  AND token = 'nS/BQrT27uaJI6gHxuHaDdN+ao7uOdRqF8gqlT4AxxQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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