SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4efa825a5b2d50af86e2e94bf6571a062b9c20f23a7782c8a23c9476a2fff7c' 
  AND token = 'BvhyeIY6BUgrKU0fpTrCTGpvF8yVE7m/EiCeCm4FdDA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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